Service Manual HP 8560A Spectrum Analyzer SERIAL NUMBERS Prefix 3207A and Above Eiia HEWLETT PACKARD HP Part No.
@Copyright Hewlett-Packard Company 1990, 1992 All Rights Reserved. Reproduction, adaptation, or translation without prior written permission is prohibited, except as allowed under the copyright laws.
Certification Hewlett-Packard Company certifies that this product met its published specifications at the time of shipment from the factory. Hewlett-Packard further certifies that its calibration measurements are traceable to the United States National Institute of Standards and Technology, to the extent allowed by the Institute’s calibration facility, and to the calibration facilities of other International Standards Organization members.
Safety Symbols The following safety symbols are used throughout this manual. Familiarize yourself with each of the symbols and its meaning before operating this instrument. Caution The caution sign denotes a hazard. It calls attention to a procedure which, if not correctly performed or adhered to, could result in damage to or destruction of the instrument. Do not proceed beyond a caution sign until the indicated conditions are fully understood and met. Warning The warning sign denotes a hazard.
HP 8560A Spectrum Analyzer Documentation Outline For ordering information, contact a Hewlett-Packard Sales and Service Office. Manuals Shipped with Your Instrument HP 8560A Installation and Verification Manual n Tells you how to install the spectrum analyzer. n Tells you what your analyzer’s specifications are. HP 856OA/8561 B/8563A 0 perating and Programming Manual w Tells you how to make measurements with your spectrum analyzer. w Tells you how to program your spectrum analyzer.
Contents 1. General Information Manual Organization . . . . . . . . . Manual Text Conventions . . . . . . . Serial Numbers Covered by This Manual . Instrument Variations . . . . . . . . . HP 85629B Test and Adjustment Module Service Kit . . . . . . . . . . . . . . Recommended Test Equipment . . . . . Electrostatic Discharge . . . . . . . . Reducing Potential for ESD Damage . Static-Safe Accessories . . . . . . . . Returning Instruments for Service . . . . Service Tag . . . . . . . . . . . .
15. 16. 17. 18. 19. 20. External Mixer Amplitude Adjustment Second IF Gain Adjustment . . . . Signal ID Oscillator Adjustment . . . 600 MHz Amplitude Adjustment . . 10 MHz Reference Adjustment (Option Tracking Oscillator Adjustment (Option . . . . . . . . . . . . 003) 002) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-57 2-60 2-63 2-66 2-68 2-71 3. Assembly Replacement Access to Internal Assemblies . . . .
6. General Troubleshooting Introduction . . . . . . . . . . . . . . . . . . . Assembly Level Text . . . . . . . . . . . . . . Block Diagrams . . . . . . . . . . . . . . . . . Assembly Test Points . . . . . . . . . . . . . . Pad.. . . . . . . . . . . . . . . . . . . . Test Jack . . . . . . . . . . . . . . . . . . Ribbon Cables . . . . . . . . . . . . . . . . . WR PROT/WR ENA Softkey Menus . . . . . . . Troubleshooting to a Functional Section . . . . . . . Using the TAM . . . . . . . . . . . . . . . . . .
Option Module Errors (800 to 899) . . . . . . . . . User-Generated Errors (902 to 904) . . . . . . . . . Block Diagram Description . . . . . . . . . . . . . . RF Section . . . . . . . . . . . . . . . . . . . . A7 LODA . . . . . . . . . . . . . . . . . . . A8 Low Band Mixer . . . . . . . . . . . . . . . A9 Input Attenuator . . . . . . . . . . . . . . All YTO . . . . . . . . . . . . . . . . . . . Al3 Second Converter . . . . . . . . . . . . . . A15Al Second IF Distribution Amplifier (P/O A15) .
Track and Hold . . . . . . A3 Assembly’s ADC Circuits . ADC Control Signals . . . ADC Start/Stop Control . . ADC ASM . . . . . . . . ADC . . . . . . . . . . Ramp Counter . . . . . . A3 Assembly’s Control Circuits Analog Bus Drivers . . . . Analog Bus Timing . . . . Interface Strobe Select . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
A4 Assembly’s Cal Oscillator Circuit . . . . . . . . . . . Cal Oscillator Unlock at Beginning of IF Adjust . . . . . Inadequate CAL OSC AMPTD Range . . . . . . . . . . 300 Hz to 3 kHz Resolution Bandwidth Out of Specification Low-Pass Filter . . . . . . . . . . . . . . . . . . . . Sweep Generator . . . . . . . . . . . . . . . . . . . AM/FM Demodulation, Audio Amplifier, and Speaker . . . 9. Controller Section Troubleshooting Using the TAM . . . Blank Display . . . . . . . . . .
Unlocked Reference PLL . . . Operation . . . . . . . . Troubleshooting . . . . . Third LO Driver Amplifier . Sampler and Sampler IF . . . Sweep Generator Circuit . . . A21 OCXO (Option 003 only) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
12. Display/Power Supply Section Troubleshooting Using the TAM . . . . . . . . Blank Display . . . . . . . . . . . . . . . Blank Display . . . . . . . . . . . . . . . . Display Distortion . . . . . . . . . . . . . . Focus Problems . . . . . . . . . . . . . . . . Intensity Problems . . . . . . . . . . . . . . A6 Power Supply Assembly . . . . . . . . . . Dead Power Supply . . . . . . . . . . . . . Line Fuse Blowing . . . . . . . . . . . . . Supply Restarting Every 1.
Figures Serial Number Label Example . . . . . . . . . . . . . . . . . . . . Example of a Static-Safe Workstation . . . . . . . . . . . . . . . . . HP 8560A Shipping Container and Cushioning Materials . . . . . . . . . High-Voltage Power Supply Adjustment Setup . . . . . . . . . . . . . Display Adjustment Setup . . . . . . . . . . . . . . . . . . . . . . CRT Adjust Pattern . . . . . . . . . . . . . . . . . . . . . . . . A2 Display Adjustment Locations . . . . . . . . . . . . . . . . . . .
3-15. RF Section Bias Connections . . . . . . . . . 3-16. A9 Mounting Screws at Right Frame . . . . . 3-17. A10 Tracking Generator Mounting Screws . . . 3-18. All Mounting Screws . . . . . . . . . . . . 3-19. Al4 and Al5 Assembly Removal . . . . . . . 3-20. Al4 and Al5 Assembly Cables . . . . . . . . 3-21. Al7 Mounting Screws . . . . . . . . . . . . 3-22. Main Deck Screws . . . . . . . . . . . . . 3-23. A6 Power-Supply Cover . . . . . . . . . . . 3-24. W3 Dress and Connection to A6 Power Supply . 3-25.
. . . . . . . . . . . . . . . 8-13. Faulty Crystal Short . . . . . . . . . . . . . . . . . . 8-14. Faulty LC Pole 8-15. Faulty Crystal Symmetry . . . . . . . . . . . . . 8-16. Output Waveform, 10 kHz Resolution Bandwidth . . . 8-17. Output Waveform, 3 kHz Resolution Bandwidth . . . 8-18. Output Waveform, 1 kHz Resolution Bandwidth . . . 8-19. Output Waveform, 300 Hz Resolution Bandwidth . . . 8-20. Failed Crystal Set Symptoms . . . . . . . . . . . . 8-21. A4 Log Amplifier Block Diagram . . . . . . . . . .
Tables l-l. Service Kit Contents . . . . . . . . . . . . . . . . . . . . l-2. Static-Safe Accessories . . . . . . . . . . . . . . . . . . . . l-3. Hewlett-Packard Sales and Service Offices . . . . . . . . . . . 1-4. Recommended Test Equipment . . . . . . . . . . . . . . . . 2-l. Related Adjustments (1 of 2) . . . . . . . . . . . . . . . . . 2-l. Related Adjustments (2 of 2) . . . . . . . . . . . . . . . . . 2-2. Adjustable Components (1 of 3) . . . . . . . . . . . . . . . 2-2.
8-4. Available Reference Level Range . . . . . . . . . . . . . . . . . . . 8-5. Signal Level for Reference Level Display . . . . . . . . . . . . . . . . 9-l. TAM Tests Versus Test Connectors . . . . . . . . . . . . . . . . . . 9-2. Gate Times . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-l. Center Frequency Tuning Values . . . . . . . . . . . . . . . . . . . 10-2. Sampling Oscillator Test Frequencies . . . . . . . . . . . . . . . . . 10-3. YTO Frequency in TEST Position . . . . . . . . . . . .
General Information This HP 8560A Spectrum Analyzer Service Manual contains information required to adjust and service the HP 8560A Spectrum Analyzer to the assembly level. For component-level information, refer to the HP 856OA/61B/63A Spectrum Analyzer Component Level Information. Manual Organization Chapter 1, General Information, contains information about service kit contents, recommended test equipment, returning an instrument for service, and sales and service offices.
Manual Text Conventions The following text conventions are used throughout this manual: m Softkeys Display Text Boxed text in this typeface represents a mechanical key physically located on the instrument. Shaded text indicates a softkey. Softkey labels appear on the display and can be activated by pressing corresponding keys surrounding the display. The labels displayed are determined by the mechanical front-panel key depressed and the instrument’s firmware.
Instrument Variations The following text lists the unique assemblies contained in the HP 8560A Options 001, 002, 003, and all combinations.
W46 added w47 added W48 added Rear-panel J 11 added Front-panel 53 deleted Front-panel J6 added HP 8560A Option 003 (Precision Frequency Reference) Al5 RF Assembly unique part number A21 OCXO added w49 added w50 added HP 8560A Option 013 (001 + 003) Al5 RF Assembly unique part number w19 added Rear-panel JlO added A21 OCXO added w49 added w50 added HP 8560A Option 023 (002 + 003) Al5 RF Assembly unique part number A10 Tracking Generator added Front dress-panel unique par
Front-panel J6 added A21 OCXO added w49 added w50 added HP 8560A Option 123 (001 + 002 + 003) Al5 RF Assembly unique part number w19 added Rear-panel JlO added A10 Tracking Generator added Front dress-panel unique part number w14 added W16 added W36 deleted W42 deleted w43 added W46 added w47 added W48 added Rear-panel Jll added Front-panel J3 deleted Front-panel J6 added A21 OCXO added w49 added w50 added General Information l-5
HP 85629B Test and Adjustment Module When attached to the spectrum analyzer’s rear panel, the HP 85629B Test and Adjustment Module (TAM) p rovides diagnostic functions for the HP 8560A. Because the TAM connects directly to the analyzer’s internal data and address bus, it controls the analyzer’s hardware directly. It would be impossible to control the hardware to the same extent either from the analyzer’s front panel or over the HP-IB.
Electrostatic Discharge Electrostatic discharge (ESD) can damage or destroy electronic components. Therefore, all work performed on assemblies consisting of electronic components should be done at a static-free workstation. Figure l-2 is an example of a static-safe work station using two kinds of ESD protection: w Conductive table mat and wrist-strap combination. n Conductive floor mat and heel-strap combination. These methods may be used together or separately.
Static-Safe Accessories Table 1-2. Static-Safe Accessories HP Part Number Description 9300-0797 Set includes: 3M static control mat 0.6 m x 1.2 m (2 ft x 4 ft) and 4.6 cm (15 ft) ground wire. (The wrist-strap and wrist-strap cord are not included. They must be ordered separately.) 9300-0980 Wrist-strap cord 1.5 m (5 ft) 9300-1383 Wrist-strap, color black, stainless steel, without cord, has four adjustable links and a 7 mm post-type connection. 9300-l169 ESD heel-strap (reusable 6 to 12 months).
2. Install the front-panel cover on the instrument. 3. Wrap the instrument in antistatic plastic to reduce the possibility of damage caused by electrostatic discharge. 4. Use the original materials or a strong shipping container that is double-walled, corrugated cardboard carton with 159 kg (350 lb) bursting strength. The carton must be both large enough and strong enough to accommodate the analyzer and allows at least 3 to 4 inches on all sides of the analyzer for packing material. 5.
SK1126 Item Description HP Part Number 1 2 9211-5636 08590-80013 Outer Carton Pads (2) 3 08590-80014 Bottom Tray Figure 1-3.
Sales and Service Offices Hewlett-Packard has sales and service offices around the world providing complete support for Hewlett-Packard products. To obtain servicing information, or to order replacement parts, contact the nearest Hewlett-Packard Sales and Service Office listed in Table l-3. In any correspondence, be sure to include the pertinent information about model numbers, serial numbers, and assembly part numbers.
Table 1-3. Hewlett-Packard Sales and Service Offices US FIELD OPERATIONS EUROPEAN OPERATIONS INTERCON OPERATIONS HEADQUARTERS HEADQUARTERS HEADQUARTERS Hewlett-Packard Company Hewlett-Packard S.A. Hewlett-Packard Company 19320 Pruneridge Avenue 150, Route du Nant-d’Avri1 3495 Deer Creek Rd. Cupertino, CA 95014, USA 1217 Meyrin 2/Geneva Palo Alto, California 94304-1316 Switzerland (800) 752-0900 (415) 857-5027 (41 22) 780.8111 California Australia Hewlett-Packard Co. France Hewlett-Packard Australia Ltd.
Table 1-4. Recommended Test Equipment Instrument Synthesized Critical Specifications for Equipment Substitution Sweeper Frequency Range: 10 MHz to 7 GHz Frequency Accuracy (CW): 1 x 10eg/day (two required) Leveling Modes: Internal & External Recommended Model Use HP 8340A* PAT, M,V HP 3335A* PAT, Modulation Modes: AM & Pulse Power Level Range: -80 to +16 dBm Synthesizer/ Level Generator Frequency Range: 200 Hz to 80 MHz Frequency Accuracy: 1 x 10e7/month M,V Flatness: f0.
Table 1-4. Recommended Test Equipment (continued) Instrument Critical Specifications for Equipment Substitution Measuring Compatible w/Power Sensors Receiver dB Relative Mode Resolution: 0.01 dB Reference Accuracy: <&1.2% Power Sensor Frequency Range: 50 MHz to 6.9 GHz Maximum SWR: 1.
Table 1-4. Recommended Test Equipment (continued) Instrument Critical Specifications for Equipment Substitution Recommended Model Use 20 dB Fixed Attenuator Frequency Range: dc to 6.5 GHz Attenuation Accuracy:
Table 1-4. Recommended Test Equipment (continued) ment Substitution Type N (m) to SMA (f) Length: 291 cm (36 in.) Cable, 5052 Coaxial Connectors: BNC (m) (five required) Cable, HP-IB (12 required) HP 10503A P,A,V HP 10833B PAM 8120-4921 P,A,M,V Tek JlG-TV A HP 9816A, HP 9836A/C, V Length: 2 122 cm (48 in.) Required w/Performance Test Software Required w/HP 85629B Test & Adjustment Module Length: 2 m (6.6 ft.) Cable (three required) Frequency Range: 10 kHz to 6.9 GHz Maximum SWR: <1.4 at 6.
2 Adjustment Procedures Introduction This chapter contains information on automated and manual adjustment procedures for the HP 8560A spectrum analyzer. Perform the automated procedures using the HP 85629B Tests and Adjustment Module (TAM). Never perform adjustments as routine maintenance. Adjustments should be performed after a repair or performance test failure. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Safety Considerations Although this instrument has been designed in accordance with international safety standards, this manual contains information, cautions, and warnings which must be followed to ensure safe operation and to prevent damage to the instrument. Service and adjustments should be performed only by qualified service personnel. Warning Adjustments in this section are performed with power supplied to the instrument and protective covers removed.
Adjustment Tools For adjustments requiring a nonmetallic tuning tool, use fiber tuning tool, HP part number 8170-0033. For adjustments to the IF Bandpass, use tuning tool, HP part number 8710-1010. Never try to force an adjustment control. This is especially critical when tuning variable capacitors or slug-tuned inductors. Required service accessories, with part numbers, are listed in “Service Kit” in Chapter 1.
Table 2-1.
Table 2-1.
Table 2-2. Adjustable Components (1 of 3) Reference Designator Adjustment Name Adjustment Number Description A2R206 DGTL X GAIN 2 Adjusts the horizontal gain in the X line generator. A2R209 SWEEP OFFSET 2 Adjusts the beginning of the trace to the leftmost vertical graticule line in fast-analog, zero-span mode. A2R215 DGTL Y GAIN 2 Adjusts the vertical gain in the Y line generator.
Table 2-2. Adjustable Components (2 of 3) Reference Designatol Adjustment Name Adjustmend Number A5T500 XTAL CTR 3 3 A5T502 XTAL CTR 4 3 A6R410 HV ADJ 1 Description Adjusts center frequency bandwidth filter to 10.7 Adjusts center frequency bandwidth filter to 10.7 of third stage of crystal MHz. of fourth stage of crystal MHz. Adjusts the voltage between A6TP405 and A6TP401 to the voltage marked on the A6Al High Voltage Module.
Table 2-2. Adjustable Components (3 of 3) Reference Designator Adjustment Name Adjustment Number Description A15R561 C A L A M P T D 11 Adjusts amplitude of the 300 MHz calibrator signal to -10.0 dBm. A15R926 E X T B I A S Z E R O 14 Adjusts zero bias point of external mixer bias. A17R4 Z GAIN 2 Adjusts maximum intensity. A17Rll CUTOFF 2 Adjusts intensity to turn off blanked lines. A17R21 Z FOCUS 2 Adjusts focus for lines of different brightness.
Using the TAM The HP 85629B TAM can be used to perform approximately half of the HP 8560A adjustment procedures. Table 2-4 lists the TAM adjustments and their corresponding manual adjustments. The TAM adjustments do not include procedures for choosing factory-selected components. If an adjustment cannot be made and a factory-selected component must be changed, refer to the corresponding manual adjustment. To select an adjustment, press (m) to display the TAM Main Menu, then press ADJUST.
Table 2-4. TAM Adjustments 1. 2. 3. 4. 5. TAM Adjustment Corresponding Manual Adjustment Adjustment Number IF Bandpass, LC Poles IF Bandpass, Crystal Poles IF Amplitude Limiter Phase Linear Fidelity IF Bandpass Adjustment IF Bandpass Adjustment IF Amplitude Adjustment DC Log Amplifier Adjustments, A4 Limiter Phase DC Log Amplifier Adjustments, A4 Linear Fidelity 3 3 4 5 5 6. Log Fidelity 7. Sampling Oscillator DC Log Amplifier Adjustments, A4 Log Fidelity Sampling Oscillator Adjustment 8.
Table 2-5. Required Test Equipment for TAM (continued) Adjustment 6. Log Fidelity Equipment Used Synthesizer/Level Generator Required Model HP 3335A HP 10503A Test Cable BNC 7. Sampling Oscillator Manual Probe Cable 8. YTO Frequency Counter (3 to 6.8 GHz) HP 5342A, HP 5343A HP 8902A, HP 436A, 9. LO Distribution Amplifier Power Meter HP 438A HP 8485A Power Sensor (3 to 6.8 GHz, 10 to 20 dBm) 10. Low Band Flatness Recommended Model Source (10 MHz to 2.
1. High-Voltage Power Supply Adjustment Assembly Adjusted A6 Power Supply Related Performance Test There is no related performance test for this adjustment. Description The high-voltage power supply is adjusted to the voltage marked on the A6Al HV Module. The A6Al HV Module is characterized in the factory to ensure that the display filament voltage is set to 6.0 V rms when the +llO Vdc ( nominal) supply is set to the voltage marked on the HV Module.
1. High-Voltage Power Supply Adjustment Equipment Digital Multimeter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HP 3456A DVM Test Leads . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HP 34118A Procedure Warning After disconnecting the ac power cord, allow capacitors in the high-voltage supply to discharge for at least 30 seconds before removing the protective cover from the A6 Power Supply. 1.
2. Display Adjustment Assembly Adjusted A2 Controller Al7 CRT Driver Related Performance Test Sweep Time Accuracy (Sweep Times <30 ms) Description Coarse adjustment of the deflection amplifiers, Z-axis amplifiers, and line generators is done using the CRT adjust pattern. Fine adjustments use the graticule. The fast zero-span amplitude adjustments correct for differences between analog and digital display modes. The displayed sweep time accuracy is adjusted in the fast zero-span sweep adjustments.
2. Display Adjustment Procedure 1. Set the analyzer’s @ switch off. Remove the analyzer’s cover and fold out the A2 Controller and A3 Interface assemblies as illustrated in Figure 2-2. Connect the CAL OUTPUT to the INPUT. Adjustment locations are shown on the CRT neck for Al7 adjustments and in Figure 2-4 for the A2 adjustments. Preliminary Adjustments 2.
2. Display Adjustment 14. Adjust the rear-panel Y POSN and A17R75 Y GAIN until the softkey labels align with their appropriate softkeys. 15. Press [m). If necessary, readjust STOP BLANK and START BLANK for the best-looking intersection of the graticule lines. This will be most noticeable along the center vertical and horizontal graticule lines.
2. Display Adjustment Intensity Adjustments 16. Press (-1 then set the REF LVL to -70 dB and the LOG dB/DIV to 1. This should almost completely fill the screen with the noise floor. Press (SWP). Adjust A17R4 Z GAIN until the intensity at the center of the screen is 15 NITS, as indicated by the TEK JlG-TV Photometer/Radiometer. 17. Press (CAL), MORE 1 of 2, and CRT ADJ PATTERN. Locate the dot just below the HP logo. Adjust A17R93 ASTIG for the smallest round dot possible.
2. Display Adjustment AZR215 A2R263 DGTLY GAIN START BLANK AZR206 DGTLY GAIN AZR262 STOP BLANK A2R268 VIDEO GAIN / SK14 Figure 2-4. A2 Display Adjustment Locations 18. Adjust A17R34 COURSE FOCUS and A17R92 DDD for the best focus of the characters at the center of the screen. 19. Adjust A17R21 Z FOCUS for the best focus of the test pattern’s outside box. 20. Adjust A17R26 X FOCUS for best focus of the “@” characters at the corners of the test pattern. 21.
2. Display Adjustment Fast Zero Span Adjustments 22. Set A2R209 SWEEP OFFSET, A2R218 VIDEO OFFSET, A2R268 VIDEO GAIN and A2R271 SWEEP GAIN to midrange. Adjustment locations are shown in Figure 2-4 for these A2 adjustments. 23. Set the HP 355D Attenuator to provide 30 dB attenuation. 24. Press (-1 on the analyzer, and connect the equipment as shown in Figure 2-2. Set the HP 8560A controls as follows: C E N T E R F R E Q . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..
3. IF Bandpass Adjustment Assembly Adjusted A5 IF Assembly Related Performance Test Resolution Bandwidth Accuracy and Selectivity Description The center frequency of each IF bandpass filter pole is adjusted by DAC-controlled varactor diodes and an inductor (for the LC poles) or a transformer (for the crystal poles). The inductors and transformers are for coarse tuning and the varactors are for fine tuning by the microprocessor.
3. IF Bandpass Adjustment Procedure 1. Set the HP 8560A m switch off and disconnect the power cord. Remove the analyzer cover and fold down the A2 Controller, A3 Interface, A4 Log Amp, and A5 IF assemblies. Reconnect the power cord and set the (LINE) switch on. Allow the analyzer to warm up for at least 30 minutes. 2. Connect the negative DVM lead to pin 6 of A5J6. See Figure 2-5. Set the HP 3456A controls as follows: FUNCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3. IF Bandpass Adjustment Table 2-6. Factory-Selected LC Filter Capacitors 1CC CTR Adjustment Fixed Factory Select Capacitor A5L300 A5L301 A5L700 A5L702 LC LC LC LC CTR CTR CTR CTR 1 2 3 4 A5C326 A5C327 A5C717 A5C718 Table 2-7. LC Factory-Selected Capacitor Selection Currentl! Y Loaded CaDacitor Value (pF) DVM Reading (V) 0 to 1.5 1.5 to 2.5 2.5 to 3.5 3.5 to 4.5 4.5 to 5.5 5.5 to 6.5 6.5 to 7.5 to 8.5 to 9.5 to 7.5 8.5 9.5 10 * Indicates a Replace 6.8 with: * Replace 8.
3. IF Bandpass Adjustment Note If the range for the XTAL CTR adjustment is insufficient, replace the appropriate factory-selected capacitor as listed in Table 2-8. To determine the correct replacement value, center the XTAL CTR adjustment, and press ADJ CURR IF STATE. After the IF ADJUST STATUS message disappears,read the DVM display. Choose a capacitor value from Table 2-9, based on the DVM reading and the presently loaded capacitor value. Table 2-10 lists a few capacitor part numbers.
3. IF Bandpass Adjustment Table 2-10. Capacitor Part Numbers Capacitor Value (pF) HP Part Number 6.8 8.
4. IF Amplitude Adjustments 4. IF Amplitude Adjustments The IF Amplitude Adjustments consist of the Cal Oscillator Amplitude adjustment and the Reference 15 dB Attenuator adjustment. Assembly Adjusted A4 Log Amp/Cal Oscillator A5 IF Assembly Related Performance Tests IF Gain Uncertainty Test Scale Fidelity Test Equipment Frequency Synthesizer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HP 3335A Adapters Type N (m) to BNC (f) . . . . . . . . . . . . . . . . . . .
4. IF Amplitude Adjustments A5 IF A4 LOG AMP J9 J7 R826 R445 J2 38 JIO (REVISION CONNECTOR) J5 Jl Jll J 4 ’ J4 R544 / J3 R531' SK190 Figure 2-7. IF Amplitude Adjustment Locations A4 Log Amp/Cal Oscillator Amplitude Adjustment This adjustment sets the output amplitude of the A4 Log Amp/Cal Oscillator and the absolute amplitude of the reference 15 dB attenuator. The output of the A4 Log Amp/Cal Oscillator is adjusted so that a -55 dBm signal applied to the 10.
4. IF Amplitude Adjustments Procedure 1. Set the HP 8560A m switch to off. Remove the analyzer cover and place the analyzer in the service position as illustrated in Figure 2-6. See Figure 2-7 for adjustment location. 2. Disconnect W29, violet coax cable, from A5J3. Connect the test cable between A5J3 and the 50 R output of the HP 3335A. Set the HP 8560A (LINE) switch on. 3. Set the HP 8560A controls as follows: C E N T E R F R E Q . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4. IF Amplitude Adjustments A5 Reference Attenuator Adjustment 12. Set the HP 3335A (AMPLITUDE) to -60 dBm. 13. Connect a BNC cable between the 50 R output of the HP 3335A and the HP 8560A INPUT 500. 14. On the HP 856OA, press (CAL) and REF LEVEL ADJUST. Use the front-panel knob or step keys to place the peak of the displayed signal 3 dB to 5 dB below the reference level. 15. On the HP 8560A press level to -10 dBm. [ PEAK SEARCH] and MARKER DELTA. Set the analyzer reference 16.
5. DC Log Amplifier Adjustments 5. DC Log Amplifier Adjustments There are three DC Log adjustments; Limiter Phase, Linear Fidelity, and Log Fidelity. These adjustment need only be done under the following conditions: Limiter Phase Only if a repair is made to blocks F, G, H, I, or J. Linear Fidelity Only if a repair is made to blocks C, D, F, G, H, I, J, K, 0, IF Gain Accuracy, RBW switching, or Log Fidelity.
5. DC Log Amplifier Adjustments Procedure 1. Set the HP 8560A m switch to off. Remove the analyzer cover and place the analyzer in the service position as illustrated in Figure 2-6. See Figure 2-7 for adjustment location. 2. Connect the HP 3335 50 0 output to the HP 8560A 50 0 input. Set the HP 8560A (LINE) switch on. 3. Set the HP 8560A controls as follows C E N T E R F R E Q . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...15 MHz SPAN . . . . . . . . . . . . .
5. DC Log Amplifier Adjustments 7. Reduce the input power by 40 dB, to -58 dBm ( use an attenuator or a source with a good relative amplitude accuracy). 8. If the signal is lower on the screen than expected (delta marker reads a change of greater than 40 dB, such as -4ldB) then adjust A4R544 ( see Figure 2-7) for an even lower level and press LCAL), ADJ CURR IF STATE . Allow sufficient time for the analyzer to complete the adjustment. 9.
5. DC Log Amplifier Adjustments A4 LOG Fidelity Adjustment This adjustment consists of adjusting A4R531 until the error is adjusted to zero. Procedure 1. Set the HP 8560A (LINE) switch to off. Remove the analyzer cover and place the analyzer in the service position as illustrated in Figure 2-6. See Figure 2-7 for adjustment location. 2. Connect the HP 3335 50 R output to the HP 8560A 50 R input. Set the HP 8560A (LINE) switch on. 3. Press [m), ICAL), IF ADJ OFF, ADJ CURR IF STATE 4.
6. Sampling Oscillator Adjustment 6. Sampling Oscillator Adjustment Assembly Adjusted Al5 RF Assembly Related Performance Test There is no related performance test for this adjustment procedure. Description The phase detector bias is adjusted for 1.8 Vdc. The sampling oscillator tank circuit is adjusted for a tuning voltage of 0.9 Vdc when the oscillator is set to 288 MHz. The voltage monitored is actually the tuning voltage divided by 4.05.
6. Sampling Oscillator Adjustment Procedure 1. Set the HP 8560A m switch to off and disconnect the line power cord. Remove the analyzer cover and fold down the Al5 RF and Al4 Frequency Control assemblies. Prop up the Al4 Frequency Control assembly. Reconnect the line power cord and set the (LINE) switch on. Connect the equipment as illustrated in Figure 2-8. 2. Press (PRESET] on the HP 8560A and set the controls as follows: CENTER FREQ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6. Sampling Oscillator Adjustment 12. Record the displayed voltage in Table 2-11 as the displayed voltage for the sampling oscillator frequency of 288 MHz. 13. Press (m) on the HP 8560A. Use the step keys to set the analyzer center frequency to the frequencies listed in Table 2-11. At each listed frequency, record the displayed voltage in the table. ’ 14. If the difference between the maximum and minimum voltages is less than 0.50 V, and all voltage readings are between to.5 and t2.
6. Sampling Oscillator Adjustment 23. Set the HP 6114A Power Supply for a 21 Vdc output 50.2 V. Connect the positive supply lead to X201 pin 1 and the negative supply lead to X201 pin 4. 24. Connect the active probe to TP201. 25. Set the HP 8560A [LINE] switch on and set the controls as follows: C E N T E R F R E Q . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..661MHz SPAN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
7. YTO Adjustment 7. YTO Adjustment Assembly Adjusted Al4 Frequency Control Assembly Related Performance Tests Frequency Span Accuracy Frequency Readout Accuracy and Frequency Count Marker Accuracy Description The YTO main coil adjustments are made with the phase-lock loops disabled. The YTO endpoints are adjusted to bring these points within the capture range of the main loop. The YTO FM coil is adjusted to place the 300 MHz CAL OUTPUT signal at the center vertical graticule in a 20 MHz span.
7. YTO Adjustment Procedure Note This adjustment cannot be performed if the analyzer preselected external mixer mode is selected. YTO Main Coil Adjustments 1. Set the HP 8560A m switch off. Remove the analyzer cover and fold down the Al5 RF and Al4 Frequency Control assemblies. 2. Disconnect the 50R termination from the 1ST LO OUTPUT. Connect the equipment as shown in Figure 2-10. Set the LuNE) switch on. 3.
7. YTO Adjustment YTO FM Coil Adjustments 13. On the HP 856OA, press (PRESET) and set the controls as follows: CENTER FREQ . . . :. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .300 MHz SPAN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...20 MHz 14. Adjust A14R76 FM SPAN until the 300 MHz CAL OUTPUT SIGNAL is aligned with the center vertical graticule line.
8. First LO Distribution Amplifier Adjustment Assembly Adjusted Al4 Frequency Control Assembly Related Performance Test First LO OUTPUT Amplitude Description The gate bias for the A7 LO Distribution Amplifier is adjusted to the value specified on A7. LO AMPTD is adjusted so that the LO SENSE voltage is 6 mV more negative than the value specified on the A7 LODA label. MEASURING RECEIVER SPECTRUM ANALYZER DVM T E S T L E A D S DIGITAL VOLTMETER SKI10 Figure 2-11.
8. First LO Distribution Amplifier Adjustment 4. Set the HP 3456A controls as follows: FUNCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . DCVOLTS RANGE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1OV RESOLUTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..lmV 5. Turn the HP 8560A m switch on. 6.
9. Tracking Generator Power Level Adjustments Assembly Adjusted A10 Tracking Generator Assembly Related Performance Test Absolute Amplitude and Vernier Accuracy Description The A10 Tracking Generator has two adjustments for setting the output power. AlOR -10 dB ADJ sets the power level when the TRK GEN RF POWER is set to -10 dBm and AlOR 0 dB ADJ sets the power level when the TRK GEN RF POWER is set to 0 dBm. The -10 dB ADJ acts as an offset adjustment while 0 dB ADJ acts as a gain adjustment.
9. Tracking Generator Power Level Adjustments SPECTRUM ANALYZER POWER SENSOR MEASURING RECEIVER mj - 1 0 db A D J \ SJll 0 db ADJ Figure 2-12. Tracking Generator Power Level Adjustments Setup and Adjustment Locations 2. Connect the Type N cable between the RF OUT 500 and RF INPUT 50R connectors on the HP 8560A. 3. Press (PRESET) on the HP 8560A and set the controls as follows: CENTER FREQ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .300 MHz SPAN . . . . . .
9. Tracking Generator Power Level Adjustments 10. Set the TRK GEN RF POWER to -10 dBm. Note the power displayed on the measuring receiver. Power at -10 dBm Setting dBm 11. Proceed with steps 12 through 14 only if the power level noted in the previous step was outside the range of -10 dBm +/-.23 dB. 12. With the TRK GEN RF POWER set to -10 dBm, adjust AlOR -10 dB ADJ for a -10 dBm +/-.l dB reading on the measuring receiver. Refer to Figure 2-12 for adjustment location. 13.
10. Frequency Response Adjustment 10. Frequency Response Adjustment Assembly Adjusted Al5 RF Assembly Related Performance Tests Displayed Average Noise Level Frequency Response Description A signal of the same known amplitude is applied to the spectrum analyzer at several different frequencies. At each frequency, the DAC controlling the flatness compensation amplifiers is adjusted to place the peak of the displayed signal at the same place on the screen.
10. Frequency Response Adjustment Equipment Synthesized Sweeper . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HP 8340A/B Measuring Receiver . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HP 8902A Power Sensor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HP 8482A Power Splitter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
10. Frequency Response Adjustment 13. Place the WR PROT/WR ENA jumper on the A2 Controller assembly in the WR PROT position.
11. Calibrator Amplitude Adjustment Assembly Adjusted Al5 RF Assembly Related Performance Test Calibrator Amplitude and Frequency Accuracy Description The CAL OUTPUT amplitude is adjusted for - 10.00 dBm measured directly at the front panel CAL OUTPUT connector. MEASUR I NG RECEIVER SPECTRUM ANALYZER Y PC BOARD PROP SK113 Figure 2-14. Calibrator Amplitude Adjustment Setup Equipment Measuring Receiver . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
11. Calibrator Amplitude Adjustment 3. Connect the HP 8482A through an adapter directly to the HP 8560A CAL OUTPUT connector. 4. Adjust A15R561 CAL AMPTD for a -10.00 dBm reading on the HP 8902A display.
12. 10 MHz Reference Adjustment (Non-Option 003 only) Assembly Adjusted Al5 RF Assembly Related Performance Test 10 MHz Reference Output Accuracy Description The frequency counter is connected to the CAL OUTPUT, which is locked to the 10 MHz reference. This yields better effective resolution. The temperature-compensated crystal oscillator (TCXO) is adjusted for a frequency of 300 MHz as read by the frequency counter. FREQUENCY COUNTER PC BOARD PROP SK114 Figure 2-15.
12. 10 MHz Reference Adjustment (Non-Option 003 only) 3. Press CjCTRL), REAR PANEL , and ensure that the 10 MHz reference is set to 10 MHz INT. Note When the 10 MHz reference is set to IO MHz EXT , the TCXO is not operating and warmed up. If the reference is set to 10 MHz EXT , set the reference to 10 MHz INT and allow 30 minutes for the TCXO to warm up. 4. Remove dust cap from A15U302, TCXO. The dust cap is toward the rear of the HP 8560A. 5.
13. Demodulator Adjustment Assembly Adjusted A4 Log Amplifier Assembly Related Performance Test There is no related performance test for this adjustment procedure. Description A 5 kHz peak-deviation FM signal is applied to the INPUT 5Ofl. The detected audio is monitored by an oscilloscope. FM DEMOD is adjusted to peak the response displayed on the oscilloscope. OSCILLOSCOPE wj SIGNAL GENERATOR ADAPTER I OUTPUT ADAPTER SK115 Figure 2-16.
13. Demodulator Adjustment Cables BNC,122cm(48in) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HP 10503A 1:l Oscilloscope Probe . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HP 10084A Procedure 1. Set the HP 8560A luNE) switch off. Place the analyzer in the service position as illustrated in Figure 2-16. 2. Connect the 1:l probe from the oscilloscope Channel 1 input to A4R718 (the end closest to A4J4).
13. Demodulator Adjustment Note It is possible to do this procedure without an oscilloscope by adjusting A4C707 FM DEMOD for the loudest audio tone from the internal speaker. This adjustment method may give broader and less accurate results than when using the oscilloscope to peak the response. 11. Set the.HP 8560A LuNE) switch to off. Disconnect the probe from A4R718.
14. External Mixer Bias Adjustment 14. External Mixer Bias Adjustment Assembly Adjusted Al5 RF Assembly Related Performance Test There is no related performance test for this adjustment procedure. Description A voltmeter is connected to the HP 8560A IF INPUT with the external mixer bias set to off. The bias is adjusted for a 0 Vdc output. Al4 F R E Q U E N C Y / ^^ - - ^ DIGITAL VOLTMETER SPECTRUM ANALYZER kRD PROP ADAPTER SK1 1 6 Al5 RF Figure 2-17.
14. External Mixer Bias Adjustment 3. On the HP 8560A press [m) EXTERNAL MIXER BIAS, then BIAS OFF. 4. Adjust A15R926 EXT BIAS ZERO for a DVM reading of 0.000 Vdc 512.5 mV.
15. External Mixer Amplitude Adjustment 15. External Mixer Amplitude Adjustment Assembly Adjusted Al5 RF Assembly Related Performance Test IF Input Amplitude Accuracy Description The slope of the flatness compensation amplifiers is determined. The user-loaded conversion losses for K-band are recorded and reset to 30 dB. A 310.7 MHz signal is applied to the power sensor and the power level of the source is adjusted for a -30 dBm reading. The signal is then applied to the IF INPUT.
15. External Mixer Amplitude Adjustment Adapters Type N (f) to SMA (f) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1250-1772 Type N (m) to BNC (f) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1250-1476 Type APC 3.5 (f) to APC 3.5 (f) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5061-5311 Cables BNC,122cm (48in) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
16. Second IF Gain Adjustment Assembly Adjusted Al5 RF Assembly Related Performance Test IF Input Amplitude Accuracy Description The gain of the Second IF (between A15J801 INT Second IF and the third mixer) is set to 12 dB. Note This adjustment is necessary after replacing either A15Al Second IF Amplifier or A15U802 Second IF pad. Equipment No test equipment or test setup is required for this adjustment procedure. Procedure 1.
16. Second IF Gain Adjustment c c c A15Al (BENEA T H 5~ I E L D ) / 1: SK118 Figure 2-19.
16. Second IF Gain Adjustment Table 2-13. A15U802 Values Second IF Amplifier Gain Range (dB) U802 Value (dB) Second IFA Pad Part Number 13.1 to 14.2 1 0955-0308 14.3 to 15.2 2 0955-0309 15.3 to 16.2 3 0955-0310 16.3 to 17.2 4 0955-0311 17.3 to 18.2 5 0955-0312 18.3 to 19.2 6 0955-0313 19.3 to 20.
17. Signal ID Oscillator Adjustment 17. Signal ID Oscillator Adjustment Assembly Adjusted Al5 RF Assembly Related Performance Test There is no related performance test for this adjustment procedure. Description The frequency range of the 298 MHz Signal ID Oscillator is determined by counting the 10.7 MHz IF as A15C629 is rotated through its range of adjustment.
17. Signal ID Oscillator Adjustment Cables BNC, 122 cm (48 in) (2 required) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HP 10503A Test Cable, BNC (m) to SMB (f) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .85680-60093 Procedure 1. Set the HP 8560A LuNE) switch off, disconnect the power cord, and remove the analyzer cover. Fold down the Al5 RF and Al4 Frequency Control assemblies. Prop up the A14 Frequency Control assembly. 2.
17. Signal ID Oscillator Adjustment 9. While observing the HP 8566A/B display, adjust A15C629 SIG ID for the highest obtainable frequency with less than 3 dB decrease in amplitude from maximum. Read this frequency from the frequency counter and record as Fs dB HIGH. Hz F3 dB HIGH = 10. Observe the HP 8566A/B display as you adjust A15C629 SIG ID for the lowest obtainable frequency with less than 3 dB decrease in amplitude from maximum. Record the frequency counter reading as Fs dB LOW.
18. 600 MHz Amplitude Adjustment Assembly Adjusted Al5 RF Assembly Related Performance Test There is no related performance test for this adjustment procedure. Description The HP 8566 Spectrum Analyzer is used to monitor the CAL OUTPUT signal of the HP 8560A. Potentiometer R726 is then adjusted to minimize the displayed noise floor and thus ensure proper input power to the ECL divide-by-two chip. Equipment Spectrum Analyzer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
18. 600 MHz Amplitude Adjustment 4. Press (INSTR PRESET) on the HP 8566 and set the controls as follows: START FREQ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10 MHz STOP FREQ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..3lOMHz RES BW . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...3 MHz VIDEO BW . . . . . . . . . . . . . . . . . . . . .
19. 10 MHz Reference Adjustment (Option 003) Assembly Adjusted A21 OCXO Assembly Note Replacement oscillators are factory adjusted after a complete warmup and after the specified aging rate has been achieved. Thus, readjustment should typically not be necessary after oscillator replacement and is generally not recommended.
19. 10 MHz Reference Adjustment (Option 003) SPECTRUM ANALYZER FREQUENCY STANDARD ELECTRONIC \ . /’ @ OOOb * 10 MHz OUTPUT / \ BNC CABLE FREO ADJ BNC CABLE BOTTOM-SIDE VIEW OF MAIN DECK SK120 Figure 2-22. 10 MHz Reference Adjustment (Option 003)/Setup and Adjustment Location 1. Connect equipment as shown in Figure 2-22 as follows: a. Set the (LINE) switch of the spectrum analyzer to on.
19. 10 MHz Reference Adjustment (Option 003) 2. Set the frequency counter controls as follows: FUNCTION/DATA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .FREQ A INPUT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .A: X10 ATTN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
20. Tracking Oscillator Adjustment (Option 002) 20. Tracking Oscillator Adjustment (Option 002) Note This is not a routine adjustment. This adjustment should only be performed if the Tracking Adjustment Range performance test has failed. Assembly Adjusted A10 Tracking Generator Assembly Related Performance Test Tracking Adjustment Range Description The centering of the tracking oscillator range is adjusted in the factory to ensure that the tracking adjustment functions properly.
20. Tracking Oscillator Adjustment (Option 002) Procedure 1. Remove the A10 Tracking Generator Assembly as described in Chapter 3. With the A10 Tracking Generator positioned next to the the HP 8560A, reconnect W14 (lo-wire ribbon cable) to AlOJl. Reconnect W48 to AlOJ8. Connect the 50 R termination to AlOJ3. 2. Connect the equipment as shown in Figure 2-23. The frequency counter provides the frequency reference for the synthesized sweeper and the HP 8560A. SPECTRUM ANALYZER BNC TEE SJ14 Figure 2-23.
20. Tracking Oscillator Adjustment (Option 002) 8. Record the frequency counter reading in Table 2-14 as Fl. 9. On the HP 8560A, press MAN TRK ADJ , (255), (Hz. Rotate the knob clockwise until the FINE TRACK ADJ is set to 255. 10. Record the frequency counter reading in Table 2-14 as F2. 11. Calculate Fcenter as shown below and record in Table 2-14. F center= (Fl + F2) / 2 12. Set COARSE TRACK ADJ to 25.
3 Assembly Replacement This chapter describes the removal and replacement of all major assemblies. The following replacement procedures are provided: Page Access to InternalAssemblies...........................................................3- 2 Cable Color Code......................................................................3- 2 Procedure 1. Analyzer Cover...........................................................3- 3 Procedure 2. Al Front Frame/Al8 CRT . . . . . . . . . . . . . . . . . . . . . . . .
Access to Internal Assemblies Servicing the HP 8560A requires the removal of the spectrum analyzer’s cover assembly and the folding down of six board assemblies. Four of these assemblies lay flat along the top of the analyzer and two lay flat along the bottom of the analyzer. All six assemblies are attached to the analyzer’s right side frame using hinges and fold out of the analyzer allowing access to all major assemblies. See Figure 3-l. n To remove the analyzer’s cover assembly, refer to Procedure 1.
Procedure 1. Analyzer Cover Procedure 1. Analyzer Cover Removal/Replacement 1. Disconnect the line-power cord, and place the analyzer on its front panel. 2. Loosen (but do not remove) the four rear-bumper screws, using a 4 mm hex wrench. Pull the cover assembly off towards the rear of the instrument. Caution When replacing the analyzer’s cover, use caution to avoid damaging any cables. 3. When installing the cover assembly, be sure to locate the cover’s air vent holes on the bottom side of the analyzer.
Procedure 2. Al Front Frame/A18 CRT Removal Warning The voltage potential at A6AlW3 is +9 kV. Disconnect at the CRT with caution! Failure to properly discharge A6AlW3 may result in severe electrical shoclc to personnel and damage to the instrument. 1. Remove the analyzer’s cover assembly as described in Procedure 1, “Analyzer Cover.” 2. Fold out the A2, A3, A4, and A5 assemblies as described in Procedure 5, “A2, A3, A4, and A5 Assemblies Removal,” steps 2 through 6. 3. Disconnect AlAlWl from A3J602. 4.
Procedure 2. Al Front Frame/Al8 CRT Warning The voltage potential at A6AlW3 is +9 kV. Failure to discharge A6AlW3 correctly may result in severe electrical shock to personnel and damage to the instrument. A6AlW3 HIGH-VOLTAGE PROBE ’\ GROMMET A6A-1 W3 SK123 Figure 3-2.
Procedure 2. Al Front Frame/Al8 CRT 1/ ,W42 (STANDARD) 4 PLACES \ \ I w47 (OPT 002) W46 (OPT 002) 5J15 Figure 3-3. A9, A18, and Line-Switch Assembly Mounting Screws 16. Remove screw (2) securing the A9 Input Attenuator Assembly to the center support on the front frame. See Figure 3-3. 17. Use a 5/16-inch open-end wrench to disconnect W41 from the front-panel INPUT 50R connector. Loosen the opposite end of W41. 18.
Procedure 2. Al Front Frame/Al8 CRT 22. Use a 9/16-inch nut driver to remove the dress nut holding the front-panel CAL OUTPUT connector to the front panel. If necessary, drill out the nut driver to fit over the BNC connectors and cover the tip with heatshrink tubing or tape to avoid scratching the enameled front panel. 23. Remove screw (3) securing the line-switch assembly to the front frame. See Figure 3-3. 24.
Procedure 2. Al Front Frame/Al8 CRT A18Wl F SK126 Figure 3-5. Installing the CRT and Front-Frame Assemblies Replacement Note Use care when handling the glass CRT EM1 shield. The glass may be cleaned using thin-film cleaner (HP part number 8500-2163) and a lint-free cloth. When installing the glass shield, face the side of the glass with the silver coated edge towards the inside of the analyzer. 1.
Procedure 2. Al Front Frame/Al8 CRT AIAIWI SK127 Figure 3-6. Placing the CRT into the Front Frame 5. Connect A18Wl to A17J5. 6. Snap CRT cable W9 onto the end of the CRT assembly. 7. Fully seat the front frame and CRT assemblies into the analyzer. 8. Secure the front frame to the analyzer’s side frames, using three flathead screws per side. See Figure 3-4. 9. Retighten the four screws securing the CRT clamps to the deck. 10.
Procedure 2. Al Front Frame/Al8 CRT 15. Connect W36, coax 86, to the front-panel IF INPUT connector. 16. Use a 5/16-inch wrench to connect W41 from the A9 Input Attenuator to the front-panel INPUT 5OQ connector. Make sure that W40, W36, and AlWl are routed between W41 and the attenuator bracket. Secure the A9 Input Attenuator bracket to the center support on the front frame using one panhead screw. See Figure 3-3 (2). 17. Place led AlWlDSl into the line-power switch assembly. 18.
Procedure 3. AlAl Keyboard/Front Panel Keys Procedure 3. AlAl Keyboard/Front Panel Keys Removal 1. Remove the front frame from the analyzer as described in Procedure 2, “Al Front Frame/A18 CRT.” 2. Place the front frame face-down on the bench and remove the front-frame center support. 3. Disconnect AlWl from AlAlJ3 and the RPG cable from AlAlJ2. 4. Remove the nine screws holding the AlAl Keyboard assembly to the front frame and remove the assembly. 5. Remove the rubber keypad.
Procedure 4. AlA RPG Removal 1. Remove the A9 Input Attenuator as described in Procedure 8, “A7 through Al3 Assemblies.” 2. Disconnect the RPG cable from the AlAl Keyboard assembly. 3. Remove the front-panel RPG knob using a number 6 hex (Allen) wrench. Use a 7/16-inch nut driver to remove the nut holding the RPG shaft to the front panel. 4. Remove the RPG. Replacement 1. Place the RPG into the front frame with the cable facing the bottom of the analyzer.
Procedure 5. Procedure 5. A2, A3, A4, and AS Assemblies A2, A3, A4, and A5 Assemblies Removal 1. Remove the analyzer’s cover. 2. Place the analyzer on its right side frame. 3. Remove the eight screws holding the A2, A3, A4, and A5 assemblies to the top of the analyzer. These screws are labeled (a), (3), and (4) in Figure 3-7. They are also labeled on the back of the A2 board assembly. 4. Remove ribbon cable W4 from A2J6. See Figure 3-7.
Procedure 5. A2, A3, A4, and A5 Assemblies SK129 Figure 3-7. A2, A3, A4, and A5 Assembly Removal Replacement 1. Place the analyzer top-side-up on the work bench. 2. Attach the assembly being installed to the two chassis hinges with two panhead screws. 3. Leave the assembly in the folded-out position and attach ribbon cables Wl and W2. 4. Attach all coaxial cables to the assembly, as illustrated in Figure 3-9. 5. Locate the cable clip on the inside of the right-side frame.
Procedure 5. A2, A3, A4, and A5 Assemblies w20 BLUE W24 GREEN w54 RED COMPONENT SIDE WHITE w20 BLUE COMPONENT BLACK A19Wl w53 BROWN -A2 WI W27 ORANGE A4 W54 RED w53 BROWN W52 WHITE VI2 w51 GRAY/YELLOW SK130 Figure 3-8.
Procedure 5. A2, A3, A4, and A5 Assemblies W52 WH I TE w29 VIOLET W27 ORANGE Figure 3-8.
A2, A3, A4, and A5 Assemblies Procedure 5. w29 COAX 7 W52 COAX 9 W27 COAX 3 W23 COAX 9 3 W25 COAX 4 w22 COAX 0 W6 SK132 Figure 3-9. Coaxial Cable Clip 7. Check to ensure that no cables will become pinched under the hinges when folding up the A4 and A5 assemblies. 8. Fold the A4 and A5 assemblies together as a unit into the analyzer. Use caution to avoid damaging any cable assemblies. The standoffs on the A5 assembly must fit into the cups on the A6 power supply top shield. 9.
Procedure 5. A2, A3, A4, and A5 Assemblies AlAlWl A 3 J602 P J P A19Wl SK133 Figure 3-10.
Procedure 6. A6 Power Supply Assembly Procedure 6. A6 Power Supply Assembly Removal Warning The A6 Power Supply and A6A1 High Voltage assemblies contain lethal voltages with lethal currents in all areas. Use extreme care when servicing these assemblies. Always disconnect the power cord from the instrument before beginning this replacement procedure. Failure to follow this precaution will represent a shock hazard which may result in personal injury. 1. Disconnect the power cord from the analyzer. 2.
Procedure 6. A6 Power Supply Assembly 16. Use a screwdriver to remove three standoffs from the A6 Power Supply assembly. 17. Remove the A6 Power Supply assembly by lifting from the regulator heatsink toward front of analyzer. Replacement 1. Attach the A6 Power Supply assembly to the analyzer’s chassis using the three standoff screws. 2. Connect Wl to A6J1, W3 to A6J2, fan power wires to A6J3, W8 to A6J4, and the line-power jack to A6JlOl. See Figure 3-11. 3.
Procedure 6. A6 Power Supply Assembly 7. Fold the A2, A3, A4, and A5 assemblies into the analyzer as described in Procedure 5, “A2, A3, A4, and A5 Assemblies Replacement,” steps 6 through 12. SK135 Figure 3-12.
Procedure 7. A6Al High Voltage Assembly Removal Warning The A6 Power Supply and A6Al High Voltage assemblies contain lethal voltages with lethal currents in all areas. Use extreme care when servicing these assemblies. Always disconnect the power cord from the instrument before beginning this replacement procedure. Failure to follow this precaution can represent a shock hazard which may result in personal injury. 1. Disconnect the power cord from the analyzer. 2.
Procedure 7. A6Al High Voltage Assembly 16. Disconnect ribbon cable A6AlWl from A6J5. See Figure 3-11. 17. Remove the two screws (1) securing two board-mounting posts to the left side frame and remove the posts. See Figure 3-13. 18. Remove the two left side-frame screws (2) securing the Al7 assembly. 19. Lift up the Al7 CRT driver assembly and disconnect A6AlW2 from A17J6. Do not remove any other cables from the Al 7 assembly. 20.
Procedure 7. A6Al High Voltage Assembly 10. Fold the A2, A3, A4, and A5 assemblies into the analyzer and secure the analyzer cover assembly as described in Procedure 5, “A2, A3, A4, and A5 Assemblies.
Procedure 8. A7 through Al3 Assemblies Procedure 8. A7 through Al3 Assemblies A separate replacement procedure is supplied for each assembly listed below. Before beginning a procedure, do the following: w Fold out the Al4 and Al5 assemblies as described in Procedure 9, “Al4 and Al5 Assemblies.” n If the All YTO or A10 Tracking Generator (Option 002) assembly is being removed, also fold down the A2, A3, A4, and A5 assemblies as described in Procedure 5, “A2, A3, A4, and A5 Assemblies.
Procedure 8. A7 through Al3 Assemblies w44 w39 W3 A7 W38 w42 (STA N D A R D ) / FL1 l A8 / W56 , WI2 w45 w47 (OPTION 002) - w 3 4 \ \ ?I\ FL2 w33 W46 (oPTIor\I 002) w43 (OPT 10~ 002 ) w57 A l 3 w35 WI0 WI6 A10 (OPTI 002) Figure 3-14.
Procedure 8. A7 through Al3 Assemblies GATE BIA WHITE/VIOLET (97) GND BLACK (0) \ SJ17 Figure 3-15.
A7 1st LO Distribution Amplifier Removal 1. Remove the two screws securing the assembly to the analyzer’s center deck. 2. Use a 5/16-inch wrench to disconnect W38 and W39 at A7Jl and J2. 3. Disconnect W42 (W43 on Option 002) at the front-panel 1ST LO OUTPUT connector. Loosen W42 (W43 on Option 002) at A7J3. 4. Remove the gate bias wire, color code 97, and W12 from the A7 assembly. 5. Remove the assembly and disconnect W34. Replacement 1.
A8 Low Band Mixer A8 Low Band Mixer Removal 1. Disconnect W34 at A15A2J1, and place the analyzer upside-down on the work bench with Al4 and Al5 folded out to the left. 2. Remove W45 from FL1 and A8Jl 3. Use a 5/16-inch wrench to loosen the semirigid coax cable connections at A8J2 and A8J3. 4. Remove the two screws securing A8 to the center deck. 5. Remove all semirigid coax cables from the A8 assembly. Replacement 1.
A9 Input Attenuator Removal 1. Disconnect W34 at A15A2J1, and place the analyzer upside-down on the work bench. 2. Remove W41 and disconnect W44 from the attenuator. 3. Remove screw (1) securing the attenuator to the front-frame center support. See Figure 3- 15. 4. Remove screw (1) securing the A9 Input Attenuator to the right side frame. See Figure 3-16. 5. Remove the attenuator and disconnect the attenuator ribbon cable. Replacement 1.
A10 Tracking Generator (Option 002) A10 Tracking Generator (Option 002) Removal 1. Use a 5/16 inch wrench to remove the Tracking Generator’s RF OUT, LO OUT, and LO IN semi-rigid cables. 2. Disconnect W14 and W16 from the Tracking Generator. 3. Remove the three screws (1) securing the Tracking Generator to the center deck. These screws are located on the top side of the center deck as illustrated in Figure 3-17. 4. Remove the Tracking Generator and disconnect W48, coax 80. CL Q (3 PLACES) Figure 3-17.
All YTO Removal 1. If the analyzer is an Option 002, remove the Tracking Generator before proceeding. 2. Place the analyzer top-side-down on the work bench. 3. Use a 5/16 inch wrench to remove W56/FL2/W57 (as a unit). 4. Disconnect W38 at the All Assembly. 5. Remove the All mounting screws (1) shown in Figure 3-18. 6. Disconnect WlO from All. SJ19 Figure 3-18. A11 Mounting Screws Replacement 1. Reconnect WlO to All. 2. Place the All Assembly in the analyzer. 3.
Al3 Second Converter Al3 Second Converter Caution Turn off the analyzer’s power when replacing the Al3 Second Converter Assembly. Failure to turn off the power may result in damage to the assembly. Removal 1. Disconnect W34 at A15A2Jl and place the analyzer upside-down on the work bench. 2. Disconnect ribbon cable W13 from the Al3 assembly. 3. Disconnect W33, coax 81, and W35, coax 92, from the Al3 assembly. 4. Disconnect W57 from A13Jl. 5.
Procedure 9. Al4 and Al5 Assemblies R e m o v a l 1. Remove the analyzer’s cover as described in Procedure 1, “Analyzer Cover.” 2. Place the analyzer on its right side frame. 3. Remove the eight screws and washers holding the Al4 and Al5 assemblies to the bottom of the analyzer. These screws are labeled 1 and 2 in Figure 3-19. A /./ P 1 1 / r SK143 Figure 3-19. Al4 and Al5 Assembly Removal Caution Washers are not captive. Loose washers in instrument may cause internal damage.
Procedure 9. Al4 and Al5 Assemblies Caution DO NOT fold the board assemblies out of the analyzer one at a time. Always fold the Al4 and Al5 assemblies as a unit. Folding out one assembly at a time binds the hinges attaching the assemblies and may damage an assembly and hinge. 4. The board assemblies are attached to the analyzer’s right side frame with two hinges. Fold both the Al4 and Al5 assemblies out of the analyzer as a unit. 5. Remove all cables from the assembly being removed. 6.
Procedure 9. Al4 and A15 Assemblies AIAI WI8 W32 Ali w2 w49 (OPTION 0 0 3 ) w50 (OPTION 0 0 3 ) w40 I w37 \ WI 1 WI4 (OPTION 0 0 2 ) Y\ W37 WI WI9 (OPTION 0 0 1 ) w35 W36 (DELETED I N OPTION 002) w29 A34 A l 5 w51 W48 3 (OPT 10~ 0 0 2 ) / SJllO Figure 3-20.
Procedure 10. Al7 CRT Driver Procedure 10. Al7 CRT Driver Removal 1. Remove the analyzer’s cover assembly and fold out the A2, A3, A4, and A5 assemblies as described in Procedure 5, “A2, A3, A4, and A5 Assemblies Removal,” steps 3 through 6. 2. Place the analyzer top-side-up on the work bench with A2, A3, A4, and A5 folded out to the right. 3. Remove two screws (1) securing the two board-mounting posts to the left-side frame, and remove the posts. See Figure 3-21. 4.
Procedure 11. Bl Fan Removal/Replacement Warning Always disconnect the power cord from the instrument before beginning this replacement procedure. Failure to follow this precaution can present a shock hazard which may result in personal injury. 1. Remove the four screws securing the fan assembly to the rear frame. 2. Remove the fan and disconnect the fan wire from the A6 Power Supply assembly. 3.
Procedure 12. BTl Battery Procedure 12. BTl Battery Warning Battery BTl contains lithium polycarbon monofluoride. Do not incinerate or puncture this battery. Dispose of discharged battery in a safe manner. Caution To avoid loss of the calibration constants stored on the A2 Controller assembly, connect the analyzer to the main power source and turn on before removing the battery. The battery used in this instrument is designed to last several years. An output voltage of +3.
Procedure 13. Rear Frame/Rear Dress Panel Removal Warning The A8 Power Supply and A6Al High Voltage assemblies contain lethal voltages with lethal currents in all areas. Use extreme care when servicing these assemblies. Always disconnect the power cord from the instrument before beginning this replacement procedure. Failure to follow this precaution can represent a shock hazard which may result in personal injury. 1. Disconnect the line-power cord from the analyzer. 2.
Procedure 13. Rear Frame/Rear Dress Panel 15. Remove the two flathead screws securing the rear-panel battery assembly, and remove the assembly. Remove the battery and unsolder the two wires attached to the battery assembly. 16. Use a 9/16-inch nut driver to remove the dress nuts holding the BNC connectors to the rear frame. If necessary, drill out the nut driver to fit over the BNC connectors, and cover it with heatshrink tubing or tape to avoid scratching the dress panel. 17.
Procedure 13. Rear Frame/Rear Dress Panel 4. Place the coax cable’s BNC connectors into the appropriate rear-frame holes as described below. Use a 9/16-inch nut driver to attach the dress nuts holding the BNC connectors to the rear frame. Rear Panel Jack 54 J5 J6 58 J9 5. For Option 001 analyzers: RF Cable W24, coax 5 W23, coax 93 W25, coax 4 W18, coax 97 W31, coax 8 Use a 5/16-inch wrench to connect W,l9, coax 83, to rear-panel connector JlO. 6.
\
Procedure 14. W3 Line Switch Cable Removal Warning Due to possible contact with high voltages, disconnect the analyzer’s line-power cord before performing this procedure. 1. Remove the analyzer’s cover assembly as described in Procedure 1, “Analyzer Cover.” 2. Fold out the A2, A3, A4, and A5 assemblies as described in Procedure 5, “A2, A3, A4, and A5 Assemblies Removal,” steps 3 through 5. 3. Disconnect AlAlWl from A3J602. 4.
Procedure 14. W3 Line Switch Cable 18. Fold out the Al4 and Al5 assemblies as described in Procedure 9, “Al4 and Al5 Assemblies Removal,” steps 3 and 4. 19. Remove the screw (1) securing W3, the line switch assembly, to the front frame. The screw is captive. See Figure 3-25. A6Al w9 w3 0 0 - 0 0 0 0 0 0 0 0 . . . 11 . . . I- SK 149 Figure 3-24. W3 Dress and Connection to A6 Power Supply 20. Remove AlWl and AlWlDSl from the line-switch assembly. Let each hang freely.
Procedure 14. W3 Line Switch Cable 21. From the top side of the analyzer, use contact removal tool, HP part number 8710-1791, to remove the four wires from the W3 connector. See Figure 3-26. With wire cutters, clip the tie wrap holding the cable to the contact housing. 22. Completely remove the cable from the instrument. 23. Remove the Al Front-Frame assembly and Al8 CRT assembly as described in Procedure 2, “Al Front Frame/Al8 CRT Removal,” steps 16 through 29. 24.
Procedure 14. W3 Line Switch Cable CONNECTOR \ L POSITION OF TIE WRAP KNUCKLE WIRE (98) WIRE (928) WIRE (8) WIRE (918) \ PLIJNGER P U S H E S C O N T A C T O U T CONNECTOR BODY ‘\ CONTACT REMOVAL TOOL WIRE SK151 Figure 3-26.
Procedure 14. W3 Line Switch Cable Replacement (Using Contact Removal Tool, HP part number 8710-1791) 1. Ensure that the action of the switch is working properly. With a pair of wire cutters, clip the tie wrap holding the cable to the contact housing of the replacement W3 assembly. 2. Using the contact removal tool, remove the four wires from the replacement cable assembly’s connector. 3. From the bottom side of the analyzer, insert the contact end of W3 through the slotted opening in the main deck.
Procedure 14. W3 Line Switch Cable 6. Attach the line-switch assembly into the front frame using the captive panhead screw. Be sure to connect the line-switch grounding lug with the screw. SK152 Figure 3-27. Side Frame Mounting Screws 7. On the top side of the analyzer, redress W3. 8. Connect W3 to A6J2. Dress W3 into the slotted opening in the deck. 9. Connect AlAlWl to A3J602. 10. Secure the power-supply cover shield to the power supply using three flathead screws.
Procedure 15. EEROM (A2U501) Removal/Replacement Caution The EEROM is replaced with the power on. Use a nonmetallic tool to remove the defective EEROM and install the new EEROM. 1. Turn the HP 8560A (LINE) switch off. Remove the analyzer’s cover assembly and fold out the A2, A3, A4, and A5 assemblies as described in Procedure 5, "A2, A3, A4, and A5 Assemblies Removal,” steps 3 through 5. 2. Turn the HP 8560A @ switch on. 3.
Procedure 16. A21 OCXO (Option 003) Procedure 16. A21 OCXO (Option 003) Removal 1. Remove the rear-frame assembly as described in Procedure 13, “Rear Frame/Rear Dress Panel Removal,” steps 1 through 22. 2. Place the analyzer on its right-side frame. 3. Fold out the Al4 and Al5 assemblies as described in Procedure 9, “Al4 and Al5 Assemblies Removal,” steps 3 and 4. 4. Remove the three screws (1) securing the OCXO to the main deck. See Figure 3-28. 5.
Replaceable Parts This chapter contains information on ordering all replaceable parts and assemblies. Locate the instrument parts in the following figures and tables: Page Table 4-l. Firmware-Dependent Part Numbers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-3 Table 4-4. Replaceable Parts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-11 Figure Figure Figure Figure Figure Figure 4-1. 4-2. 4-3. 4-4. 4-5. 4-6.
Direct Phone-Order System Within the USA, a phone order system is available for regular and hotline replacement parts service. A toll-free phone number is available, and Mastercard and Visa are accepted. Regular Orders: The toll-free phone number, (800) 227-8164, is available 6 am to 5 pm, Pacific standard time, Monday through Friday. Regular orders have a four-day delivery time. Hotline Orders: Hotline service for ordering emergency parts is available 24 hours a day, 365 days a year.
Table 4-2.
Table 4-2.
Table 4-2.
Table 4-2. Reference Designations, Abbreviations, and Multipliers (4 of 4) ABBREVIATIONS U UCD UF UH UL VAR Variable VDC Volts-Direct Current Microcandela Microfarad Microhenry Microliter, Underwriters’ Laboratories, Inc.
Table 4-3. Manufacturers Code List (1 of 3) Mfr.
Table 4-3. Manufacturers Code List (2 of 3) Mfr.
Table 4-3. Manufacturers Code List (3 of 3) Mfr.
Table 4-4. Replaceable Parts Reference Designation HP Part Number <: -I: Gi - Description Mfr Code Mfi Part Number ACCESSORIES SUPPLIED 1810-0118 1 1 TERMINATION-COAXIAL SMA; 0.
Table 4-4. Replaceable Parts (continued) Reference Designation HP Part Number 0515-0889 c 0515-1241 0515-1331 5061-9501 5061-9685 0515-1106 8710-1755 5958-6573 6 5 9 0 2 9 0 D s sty - Description Mfr Code SCREW-MACH M3.5 x 0.6 GMM-LG Mfi Part Number 28480 0515-0889 SCREW-MACH M5 x 0.8 12MM-LG PAN-HD 28480 0515-1241 SCREW-METRIC SPECIALTY M4 x 0.7 THD; 7MM 28480 0515-1331 FRONT HANDLE ASS’Y 28480 5061-9501 MOUNT FLANGE 28480 5061-9685 SCREW-MACH M4 x 0.
Table 4-4.
Table 4-4. Replaceable Parts (continued) Reference Designation HP Part Number Al3 5086-7812 Al4 See Tbl A-l G T 1 Description Mti Code Mfr Part Number SECOND CONVERTER 28480 5086-7812 FREQUENCY CONTROL ASSEMBLY 28480 See Tbl A-l (Includes A14A101, 102, and 103) Al5 See Tbl A-l 1 RF ASSEMBLY 28480 See Tbl A-l (Opt. 001) See Tbl A-l 1 RF ASSEMBLY 28480 See Tbl A-l (Opt. 002) See Tbl A-l 1 RF ASSEMBLY 28480 See Tbl A-l (Opt.
Table 4-4. Replaceable Parts (continued) Bl HP Part Number 5061-9036 iG r BTl 1420-0341 1 Reference Designation Description FAN ASSEMBLY (Includes Wire) Mfr Part Number 28480 5083-9036 BATTERY 3.0 V 1.
Table 4-4. Replaceable Parts (continued) Reference Designation HP Part Number Description - MfiCode Mfr Part Number ASSEMBLY SHIELDS (continued: A4 Assembly 5021-991: 5021-991: 5021-9914 5021-991: 0515-1486 0515-208C 2190-0582 0905-0375 I 7 s a 1 8 9 2 1 AMP 1 (BOTTOM) 2848C 5021-991: 1 AMP 1 (TOP) 2848C 5021-991: 1 AMP 2 (TOP) 2848C 5021-9911 1 AMP 2 (BOTTOM) 2848C 5021-991: SCREW SMM 2.5 10 PNTROX SCREW M2.5 14L WSHR LK M2.5ID O-RING .
Table 4-4.
Table 4-4. Replaceable Parts (continued) Reference Designation HP Part Number W16 (Opt. 002) 08560-60001 W18 5062-0721 Gi r 8 1 Description Mfi Code Mfr Part Number CABLE ASSEMBLY, A10 ALC EXT (Rear Panel Jll to AlO) 2848( 08560-6000. CABLE ASSEMBLY, COAX 97, LO SWEEP 28480 5062-0721 28480 5062-0723 CABLE ASSEMBLY, COAX 6,0 SPAN VIDEO 28480 5062-0717 0.5 V/GHz (A14J7 to Rear Panel JS) iv19 (Opt.
Table 4-4.
Table 4-4. Replaceable Parts (continued) Reference Designation HP Part Number C QtY Description D MG Mfr Part Code Number w51 5062-6478 5 1 CABLE ASSEMBLY, COAX 84, 10 MHz REF2 (A15J304 to A4J7) W52 5062-6477 4 1 CABLE ASSEMBLY, COAX 9, 10.
4-20 Replaceable Parts
BOTTOM VIEW kern Description Mfi Code SCREW-MACH M3 x 0.5 30MM-LG PAN-HD SCREW-MACH M3 x 0.5 GOMM-LG PAN-HD SCREW-MACH M3 x 0.5 lOOMM-LG PAN-HD WASHER-FL MTLC NO. 4 .125-IN-ID SCREW-MACH M3 x 0.5 GMM-LG PAN-HD 28480 28480 28480 28480 28480 Figure 4-1.
4-22 Replaceable Parts
Parts List, Cover Assembly (See Figure 4-2) Item 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 HP Part Number 5041-8911 5041-8912 0515-1114 1460-2164 5021-6343 5021-6344 5021-8667 5001-8728 0515-1367 0515-1133 5001-8800 5041-7238 5041-3989 5041-8913 0515-1114 5041-8907 0900-0024 2190-0587 0515-1218 08562-80028 C D 1 2 2 0 7 8 2 4 0 5 3 3 3 3 2 5 8 3 7 -1 Qty Description Mfi Code 1 ~2 ~4 2 2 2 2 2 6 2 1 1 1 2 2 2 4 4 4 1 i BAIL HANDLE TRIM CAP SCREW MACH M4 X 0.
4-24 Replaceable Parts
Parts List, Main Chassis (See Figure 4-3) c 0515-1079 5180-9023 0515-1826 3050-0891 5063-0249 3 iG -7 2 3 0 3 7 3 7 1 8 3 3 1 3 4 1 1 7 2 22 0515-1590 5041-7246 0515-1079 5041-8961 5021-5486 5001-5870 3050-0891 0515-1079 5001-8705 5001-5872 0515-1367 0515-1461 5021-7464 0515-1367 0515-1461 0515-1461 0515-1461 Item 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 HP Part Number D 1 2 7 3 3 4 7 3 1 1 7 4 9 2 5 1 7 4 9 2 9 2 9 2 23 5021-5484 5 5 24 5062-075
4-26 Replaceable Parts
Parts List, RF Section (See Figure 4-4) Item 1 2 3 4 5 6 7 8 9 10 11 (Opt. 002) 12 13 14 15 16 17 18 19 20 21 22 :Option 003) iG T HP Part Number 0515-0886 0515-0886 0515-0886 5021-6749 2 2 1 0515-0886 5001-8705 0515-0890 5001-8755 0515-0890 2360-0507 3 7 9 7 9 8 2 1 2 1 2 3 2360-0183 0515-0866 0515-1146 5001-8731 6 9 0 9 4 1 2 1 18560-00002 0515-0886 0515-1461 1 2 1 0515-1461 0515-0890 4 3 Mfr Description SCREW-MACH M3 X 0.5 GMM-LG PAN-HD SCREW-MACH M3 X 0.
4-28 Replaceable Parts
[ten - HP Part Number 1 2 3 4 0515-1622 5041-8906 1000-0897 0370-3069 at: 4 1 1 1 Parts List, Front Frame (See Figure 4-5) Description SCREW-SKT-HD-CAP M4 X 0.7 8MM-LG CRT BEZEL RF1 CRT FACEPLATE KNOB BASE l-1/8 JGK .252-IN-IO MG Code Mfr Part 2848C 2848C 2848C 2848C 0515-1622 5041-8906 1000-0897 0370-3069 Number (INCLUDES ITEM 5) 3030-0022 2950-0043 2 2 SCREW-SET 6-32 .125-IN-LG SMALL CUP-PT NUT-HEX-DBL-CHAM 3/8-32-THD .
4-30 Replaceable Parts
Parts List, Rear Frame (See Figure 4-6) Iten Qty Description Mfk Code Mfr Part Number 0515-0890 9 5062-7755 3 2 1 SCREWMACH M3 X 0.5 GMM-LG SODEG-FLH-HD BATTERY HOLDER (INCLUDES WIRES) 28480 28480 0515-0890 5062-7755 2 5 0 4 1 4 28480 28480 28480 0515-1669 3160-0309 0380-0012 4 6960-0023 9 1250-1753 4 1 2 SCREW-MACH M4 X 0.7 40MM-LG PAN-HD FAN GRILLE SPACER-RND .875-IN-ID NOT ASSIGNED PLUG-HOLE TR-HD FOR 0.5-D-HOLE STL PLUG-HOLE DOME-HD FOR 0.
4-32 Replaceable Parts
5 Major Assembly and Cable Locations Introduction This chapter identifies the module’s assemblies and cables and contains the following figures: Page Figure Figure Figure Figure Figure Figure Figure Figure 5-l. 5-2. 5-3. 5-4. 5-5. 5-6. 5-7. 5-8. Hinged Assemblies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-4 Top View (A2 Unfolded) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-4 Top View (A2 and A3 Unfolded) . . . . . . . . . . .
Assemblies ....................................................... ..Figure A19 HP-IB . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..5-4 A20 Battery Assy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..5-8 A21OCXO (Option003) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..5-4 Bl Fan . . . . . . . . . . . . . . . . . . . . . . . . .
Cables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..Figure W34 First LO Samp. (Coax 0) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-5, 5-6, 5-7 W35 Int Second IF (Coax 92) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-5, 5-7 W36 Ext Second IF (Coax 86) (Deleted in Opt. 002) . . . . . . . . . . . . . . . . . . . . . . . 5-5 W37 10 MHz Ref 1 (Coax 85) . . . . . . . . . .
/ A3 nnnu noon 0000 0000 noon n o o n A l 5 SK155 Figure 5-l. Hinged Assemblies w20 W24 A3 AIAIWI W25 W2 W23 A3Wl w20 COMPONENT A19Wl W6 Wl / \ *w53 A2 SK156 Figure 5-2.
w54 A4 \ w55 SK157 W27 Figure 5-3.
W27 Wl A5 W52 A19Wl \ \ / w29 AlAlWl A19 w3 W8 w4 w9 . A6Al / I / A21 (OPTION 003) A l 6 \ A l 7 \ w55 \ LSI \ A18 SK158 Figure 5-4.
W2 (OPTION WI9 (OPTION w49 003) W50 (OPTION 0 0 3 ) 001) W36 (DELETED IN OPTION 002) w40 W29 w34 W22 \ w 3 1 w 3 7 - A l 5 WI7 / W32 W48 A (OPTION 0 0 2 ) / w3-3 Figure 5-5.
AIAI WI8 W32 / A14 I wj7 \ WI 1 ‘WI4 ( ‘ O P T 10~ Figure 5-6.
w44 w3 w39 A7 W42 (STANDARD) W38 / FL1 / W56 , w45 - w 3 4 w47 ( OPT WI2 / ION 002) FL2 \ 3\ w33 W46 ( OPT ION 002) w43 (OPTION 002) w57 A l 3 w35 WI0 A10 (OPTI 002) WI6 . w 4 1 A3 \ WI4 (OPT 10~ 002 ) Al 1 O N SJlll Figure 5-7.
BTl/A20 Bl Figure 5-8.
6 General Troubleshooting Introduction This chapter provides information needed to troubleshoot the instrument to one of the six major functional sections. Chapters 7 through 12 cover troubleshooting for each of these sections. Before troubleshooting, read the rest of this introduction. To begin troubleshooting, refer to “Troubleshooting to a Functional Section” in this chapter. Topic Page Troubleshooting to a Functional Section . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Assembly Test Points The analyzer’s board assemblies contain four types of test points: post, pad, extended component lead, and test jack. Figure 6-l illustrates each type of test point as seen on both block diagrams and circuit boards. The name of the test point will be etched into the circuit board next to the test point (for example, TP2). In some instances, the test point will be identified on the board by its number only.
TEST POINTS ON BLOCK DIAGRAM TP3 TEST JACK PIN NAME Q TPI TP2 @AMPLIFIER TEST JACK J4-MS8 /--- P I N N U M B E R (J4-15j TEST POINTS ON CIRCUIT BOARD ASSEMBLY TPI ( P O S T ) , J4 (TEST JACK) \ r: ;_;::> TP2 cpAD;;PONENT LEAD) SK163 Figure 8-1.
. WI POWER CABLE CONNECTIONS 46 l 44 ‘.42 . 40 38 D GND l D GND . 36 l 34 A GND D G N D 032 3 . 30 +5v l 28 +15v . 26 -15v l 24 P W R U P 022 2 020 1 A G N D . 18 - 1 5 v l 16 -15v A GND *SCAN RAMP NC A GND 45 43 41 39 37 35 33 1 29 27 25 23 1 9 17 POWER FOR CONTROLLER AND INTERFACE ONLY l l . . . . . . . 15 . 4’ A GND 0 GNC +5v +5v +15v -15v +2av f15V +15v A GND -12.6V NC A GND NC NC A GND NC (PROBE D G N D 013 D GND 0 1 5 A GND l l7 D G N D 019 +5v l 21 +5V . 2 3 +lSV .
/ REAR PANEL J3 A2J6 OAl5 . 1 5 OAl4 0I 1 7 . 1 6 L O P T IDENT 1 8 . IO A 1 3 O D 6 . ,D 9 . OD5 D GND i 8.7. O D 4 003 . 6 5 . D GND ODZ l 4 3. ODl D GND . 2 1 l ODO A2J2 A3J401 D GND . 11 D GND I 0 13 D GND 1. 15 12 . L K E Y R P G I R G 1 4 . I +10” R E F 1 6 .I N C A3Wl I NTERFACE CABLE CONNECTIONS AZJ5 REAR P A N E L J2 A19Jl A19Wl HPIB C A B L E CONNECTIONS SK165 Figure 6-2.
WR PROT/WR ENA Softkey Menus The jumper on jack A2J12 is shipped from the factory in the WR PROT (write protect) position (jumper on pins 2 and 3). W hen the jumper is set to the WR ENA (write enable) position (jumper on pins 1 and 2), an alternate softkey menu is displayed under (CAL). Figure 6-3 illustrates those areas of the (CAL) menu that are unique to the WR ENA mode of operation.
L E LO / % IF PATTERN IF ADJ ON OFF ADJ CURR IF STATE FREQ DIAGNOSE FULL IF ADJ REF LVL ADJ MORE 1 OF 2 t i Ei J 7 SERVICE CAL DATA MORE 2 OF 2 Lu J FLATNESS STORE DATA Figure 6-3.
Troubleshooting to a Functional Section 1. Refer to Table 6-l for the location of troubleshooting information. 2. If the HP 85629B Test and Adjustment Module (TAM) is available, refer to “Using the TAM” in this chapter. 3. If error messages are displayed, refer to “Error Messages” in this chapter. You will find both error descriptions and troubleshooting information. 4. If a signal cannot be seen, and no errors messages are displayed, the fault is probably in the RF Section.
Table 6-1. Location of Assembly Troubleshooting Texi Instrument Assembly Location of Troubleshooting Text AlAl Keyboard Chapter 7. ADC/Interface Section AlA RPG Chapter 7. ADC/Interface Section A2 Controller Chapter 9. Controller Section A3 Interface Chapter 7. ADC/Interface Section Chapter 8. IF Section A4 Log Amplifier/Cal Oscillator Chapter 8. IF Section A5 IF Chapter 8. IF Section A6 Power Supply Chapter 12. Display/Power Supply Section A6Al HV Module Chapter 12.
Using the TAM When attached to the spectrum analyzer’s rear panel, the HP 85629B Test and Adjustment Module (TAM) p rovides diagnostic functions for supporting the HP 8560A. Because the TAM is connected directly to the analyzer’s internal data and address bus, it controls the analyzer’s hardware directly through firmware control. It would be impossible to control the hardware to the same extent either from the analyzer’s front panel or over the HP-IB.
Note The HP 85629B Test and Adjustment Modules with firmware revision A or B will not properly execute Automatic Fault Isolation on the HP 8560A Spectrum Analyzer. Note HP 8560A Spectrum Analyzers with serial prefix 3207A and above have the TAM firmware residing in the spectrum analyzer. The TAM will use this firmware regardless of the firmware revision in the HP 85629B. TAM Requirements For the TAM to function properly, certain parts of the analyzer must be operating properly.
Inconsistent Results Many of the signals measured by the TAM are digitally controlled. If inconsistent results are obtained, or if failures appear in unrelated areas, the digital control may be at fault. Refer to the manual troubleshooting procedures for those assemblies to isolate those failures.
ADC/lnterface Check The keyboard interface and strobe-select circuitry must be functioning correctly, since these are required to operate the TAM. The TAM checks the ADC by attempting to measure three signals from three different locations. This ensures that an open or short in one cable will not hide the fact that the ADC is operating satisfactorily. The analog bus (W2 Control Cable) is checked by sending data out on the data lines and reading the data back.
printer is connected, press Print Page to provide a hard copy of the currently displayed screen (the softkey labels will not be printed). Each test connector has fifteen pins (one pin is missing to act as a key). The pins contain eight measured signal lines (measured signal lines denoted as MS1 through MSS), one input signal line (OSl), one ground, and five pins encoding a five-bit connector address. The TAM needs to probe each assembly’s Revision Connector once; subsequent readings are not necessary.
Error Messages The spectrum analyzer displays error messages in the lower right-hand corner of the display. A number, or error code, is associated with each error message. These error messages alert the user to errors in spectrum analyzer function or use. Multiple error messages may exist simultaneously. Refer to “Viewing Multiple Messages” below. The following information can be found in this section: Page Viewing Multiple Messages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Error Message Elimination When an error message is displayed, always perform the following procedure. 1. Press ISAVE] and SAVE STATE. 2. Store the current state in a convenient STATE register. (It may be necessary to set SAVELOCK to OFF.) 3. Press ICAL) and REALIGN LO % IF . Wait for the sequence to finish. 4. Press (RECALL) and RECALL STATE. 5. Recall the previously stored STATE. 6. If an error message is still displayed, refer to the list of error messages below for an explanation of the error messages.
' 124 NOP IBLK I-block format not valid here. 125 NOP STRNG Strings are not valid for this command. 126 NO ? This command cannot be queried. 127 BAD DTMD Not a valid peak detector mode. 128 PK WHAT? Not a valid peak search parameter. 129 PRE TERM Premature A-block termination. 130 BAD TDF Arguments are only for TDF command. 131 ?? AM/FM AM/FM are not valid arguments for this command. 132 !FAV/RMP FAV/RAMP are not valid arguments for this command.
LO and RF Hardware/Firmware Failures (300 to 399) YTO Loop Errors (300 to 301) These errors often require troubleshooting the Al4 Frequency Control assembly (Synthesizer Section) or the ADC circuits. 300 YTO UNLK YTO (1st LO) Loo p is unlocked. The ADC measures YTO-ERR voltage under phase-lock condition. 301 YTO UNLK YTO Loop is unlocked. Same as ERR 300 except ERR 301 is set if the voltage is outside certain limits.
307 FREQ ACC Transfer oscillator pretuned DAC out of range. The transfer oscillator pretune procedure attempts to find pretuned DAC values by programming the PLL to 25 different frequencies and incrementing the transfer oscillator pretune DAC until XFRSENSE changes polarity. ERR 307 is set if the DAC is set to 255 (maximum) before XFRSENSE changes polarity. 308 FREQ ACC Offset oscillator pretune DAC not within prescribed limits at low frequency.
315 FREQ ACC Indicates problems in the span calibration. Troubleshoot any unlocks before attempting to troubleshoot span calibration problems, because the loops must all lock in order to perform the calibration. If LO spans greater than 1 MHz are correct, check A14U114B , A14U115A, A14U116, or A14QlOl. This error message appears when the roller Span Attenuator DAC is out of range. This DAC value is recalculated each time there are changes to the span or start frequency.
324 FREQ ACC Unable to adjust MAINSENSE c1 ose to 0 volts using the coarse adjust DAC. The coarse adjust and fine adjust DAC are used together to set MAINSENSE to 0 volts with the loop opened. ERR 324 is set if the coarse adjust DAC cannot bring MAINSENSE close enough to 0 volts for the fine adjust DACs to bring MAINSENSE to exactly 0 volts. 325 FREQ ACC Unable to adjust MAINSENSE to 0 volts using the fine adjust DAC.
YTO Leveling Loop (334) This error often requires troubleshooting the Al4 Frequency Control assembly or A7 LODA (Synthesizer Section) or the ADC circuits. 334 LO AMPL 1ST LO Distribution Amplifier is unleveled. This error is usually accompanied by error codes 300 or 301. ERR 301 YTO UNLK is cleared once ERR 334 has been cleared. Check the output of the All YTO with the jumper on A14J23 in the TEST position. The YTO power output should be between +9 and +13 dBm.
3. If ERR 581 or ERR 582 appears, the fault is most likely caused by the Cal Oscillator. Refer to errors 581 and 582. 4. If ERR 581 or ERR 582 does not appear, troubleshoot the A5 IF assembly. Multiple IF Errors During IF adjust: If a FULL IF ADJ sequence (pressing ICAL) and FULL IF ADJ ) results in IF errors while displaying IF ADJUST STATUS: AMPLITUDE, A4 Cal Oscillator might not be providing the correct output signal. Perform the following steps: 1. Disconnect W30 (white) from A5J4. 2.
425 RBW 3K Unable to adjust 3 kHz Resolution Bandwidth in first XTAL pole. 426 RBW 3K Unable to adjust 3 kHz Resolution Bandwidth in second XTAL pole. 427 RBW 3K Unable to adjust 3 kHz Resolution Bandwidth in third XTAL pole. 428 RBW 3K Unable to adjust 3 kHz Resolution Bandwidth in Fourth XTAL pole. 429 RBW 100 Unable to adjust 100 Hz Resolution Bandwidth. ADC Handshake. 430 RBW 300 Unable to adjust 300 Hz Resolution Bandwidth. ADC Handshake.
460 AMPL Unable to adjust first step gain stage. Lin to log conversion AMPLG. 461 AMPL Unable to adjust second step gain stage. Lin to log conversion AMPL7. 462 AMPL Unable to adjust second step Gain stage. Lin to log conversion AMPL8. 463 AMPL Unable to adjust third step Gain stage. Lin to log conversion AMPLS. 464 AMPL Unable to adjust third step Gain stage. Lin to log conversion AMPLlO. 465 AMPL Unable to adjust third step Gain stage. Lin to log conversion AMPLll.
495 RBW IOK Unable to adjust 10 kHz Resolution Bandwidth. XTAL SWP GAIN 496 RBW 100 Unable to adjust 100 Hz Resolution Bandwidth. Inadequate Q, 497 RBW 100 Unable to adjust 100 Hz Resolution Bandwidth. Alignment problem. 498 RBW 100 Unable to adjust 100 Hz Resolution Bandwidth. Gain. 499 CAL UNLK Cal Oscillator is unlocked. Verify the unlocked conditions as follows: 1. Place A4 in its service position and disconnect W51 (gray-yellow) from A4J7. 2.
510 AMPL .3M Unable to adjust amplitude of 300 kHz Resolution Bandwidth. Insufficient gain during LC BW Cal. 511 AMPL IM Unable to adjust amplitude of 1 MHz Resolution Bandwidth. Insufficient gain during LC BW Cal. 512 RBW 100 Unable to adjust 100 Hz Resolution Bandwidth. Insufficient gain during crystal BW Cal. 513 RBW 300 Unable to adjust 300 Hz Resolution Bandwidth. Insufficient gain during crystal BW Cal. 514 RBW IK Unable to adjust 1 kHz Resolution Bandwidth.
531 RBW (300 Flatness correction data for Resolution Bandwidths <300 Hz not acceptable. 532 RBW <300 Absolute gain data for Resolution Bandwidths ~300 Hz not acceptable. 533 RBW <300 ADC timeout using <300 Hz Resolution Bandwidth. 534 RBW (300 Unable to do frequency count of CAL OSC using IF down-converter. 535 RBW <300 Unable to obtain adequate FM demod range to measure 500 Hz IF filter.
564 LOG AMPL Unable to adjust amplitude of log scale. No compression in CalLogPower . 565 LOG AMPL Unable to adjust amplitude of log scale. Gain compression error in CalLogPower. 566 LOG AMPL Unable to adjust amplitude of log scale. Unable to set LOG CAL LVL in CalLogPower 567 LOG AMPL Unable to adjust amplitude of log scale. No TOS LX in CalLogExpand. Possible problem in Log offset/Log Expand stage. 568 LOG AMPL Unable to adjust amplitude of log scale. No LVL LX in CalLog Power.
582 AMPL Unable to adjust 100 kHz and 210 kHz Resolution Bandwidths. Bad CALOSC Calibration in Sweep Rate. Test the 100 kHz Resolution Bandwidth filter 3 dB bandwidth as follows: 1. Connect the CAL OUTPUT signal (A4J8) to the INPUT 50R. 2. Press (PRESET) and set the controls as follows: CENTER FREQ . . . . . . . . . . . . . . . . . . . . . . . . . . .300 MHz SPAN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 500kHz Resolution Bandwidth . . . . . . . . . . . . . . . . . . . . . .
585 RBW 300K Unable to adjust 300 kHz Resolution Bandwidth. SYSBW and LCBW disagreement in LCCAL. 586 RBW IM Unable to adjust 1 MHz Resolution Bandwidth. SYSBW and LCBW disagreement in LCCAL. 587 RBW 30K Unable to adjust 30 kHz Resolution Bandwidth. SYSBW and LCBW disagreement in LCCAL. 588 RBW IOOK Unable to adjust 100 kHz Resolution Bandwidth. SYSBW and LCBW disagreement in LCCAL. 589 RBW 300K Unable to adjust 300 kHz Resolution Bandwidth. SYSBW and LCBW disagreement in LCCAL.
The EEROM on A2 is used to store data for frequency response correction, elapsed time, focus, and intensity levels. Error codes from 700 to 703 indicate that some part of the data in EEROM is invalid. An EEROM error could result from either a defective EEROM or an improper sequence of storing data in EEROM. Check the EEROM with the following steps: 1. Place the WR PROT/WR ENA jumper on the A2 Controller assembly in the WR ENA position. 2.
708 ROM U309 Check-sum error of program ROM A2U309. 709 ROM U310 Check-sum error of program ROM A2U310. 710 ROM U311 Check-sum error of program ROM A2U311. RAM Check Errors (711 to 719) The instrument power-on diagnostics check the program RAM. This includes the two RAMS used for STATE storage. If any STATE information is found to be invalid, all data in that RAM is destroyed. A separate error code is generated for each defective program RAM. All RAM is battery-backed.
Model Number Error (719) If this error occurs, return the instrument to a service center for repair. 719 MODEL #? Could not read ID string from EEROM A2U501. System Errors (750 to 757) These errors often require troubleshooting the A2 Controller and A3 Interface assemblies. 750 SYSTEM Hardware/firmware interaction; check other errors. 751 SYSTEM Hardware/firmware interaction; check other errors. 752 SYSTEM Hardware/firmware interaction; check other errors.
Block Diagram Description The spectrum analyzer is comprised of the six main sections listed below. See Figure 6-4. The following descriptions apply to the Simplified Block Diagram and Overall Block Diagram located at the end of this chapter. Assembly level block diagrams are located in Chapters 7 through 12. ; RF SECTION IF SECTION Figure 6-4.
RF Section The RF Section includes the following assemblies: A7 LODA (LO Distribution Amplifier) A8 Low Band Mixer A9 Input Attenuator A10 Tracking Generator (Option 002) All YTO (YIG-Tuned Oscillator) Al3 Second Converter Al4 Frequency Control Assembly (also in Synthesizer Section) Al5 RF Assembly (also in Synthesizer Section) FLl, 2 Low-Pass Filters The RF Section converts all input signals to a fixed IF of 10.7 MHz.
Al3 Second Converter The Al3 Second Converter down-converts the 3.9107 GHz 1st IF to a 310.7 MHz 2nd IF. The converter generates a 3.6 GHz second LO by multiplying a 600 MHz reference. Bandpass filters remove unwanted harmonics of the 600 MHz driving signal. First IF and 2nd LO signals are filtered by cavity filters. A15Al Second IF Distribution Amplifier (P/O A15) The A15Al SIFA (Second IF Distribution Amplifier) amplifies and filters the second IF.
All YTO Spanwidth 20.1 MHz to 3.8107 GHz 1.01 MHz to 20.0 MHz 100 kHz to 1 MHz 100 Hz to 100 kHz Sweep Applied To All YTO’s main coil All YTO’s FM coil Roller Oscillator PLL’s Main Oscillator Roller Oscillator PLL’s Offset Oscillator When the sweep ramp is applied to one of the PLLs, the analyzer must prevent this loop from trying to compensate for changes in the output frequency. To accomplish this, the analyzer breaks the PLL by switching the output of the PLL’s phase detector to ground.
,- Y T O PLL7 / R O L L E R O S C I L L A T O R P L L \ 1ST L O O U T P U T 3.0 - 6.81 GHz I YTO I I I AL t / O F F S E T L O C K LOOP? 10 M H z T C X O SK168 Figure 6-5. Phase Lock Loops Roller Oscillator PLL (P/O A14) This PLL’s output serves as the reference frequency for the YTO PLL. A one-to-one relationship in frequency tracking exists between the Roller Oscillator PLL and the YTO. (A change of 1 MHz in the Roller Oscillator PLL will produce a 1 MHz change in the YTO frequency.
The HP 8560A uses trace-data manipulation to generate the 5 dB/DIV scale from the 10 dB/DIV scale. The A3 Interface Assembly amplifies and offsets the 10 dB/DIV video to generate the 2 dB/DIV scale. The 1 dB/DIV scale is generated from the 2 dB/DIV scale through trace data manipulation. The first 50 dB of IF gain (log and linear mode) is achieved using the A5 assembly’s linear step-gain amplifiers. The A4 assembly’s video-offset circuit provides the remaining 60 dB of log mode IF gain.
An Automatic IF Adjustment, in analyzer firmware, sets center frequency and 3 dB bandwidth of all filter poles through varactor and PIN diodes. The firmware also controls crystal-pole symmetry and the step gain amplification. ADC/Interface Section The ADC/Interface Section is the link between the Controller Section and the rest of the spectrum analyzer. It controls the RF, Synthesizer,and IF sections through address and data lines on the W2 Control Cable (Analog Bus).
ADC The HP 8560A uses a successive-approximation type of ADC. The ADC Algorithmic State Machine (ADC ASM) controls the interface between the Start/Stop Control and the ADC itself, switching between positive and negative peak detectors when the NORMAL detector mode is selected, and switching the Ramp Counter into the ADC for comparison to the analog sweep ramp. Log Expand/Video Functions (P/O A3) The A3 Interface assembly performs log expand and offset functions.
EEROM The EEROM stores important amplitude-related correction data. This includes data for mixer-bias DACs, and RF Gain DACs (flatness correction). The analyzer serial number, model number, and installed options are also stored in EEROM. Firmware The analyzer firmware reads the model number and installed options from the EEROM to determine how to respond to certain keystrokes. Display ASM Much of the miscellaneous digital control is performed by A2UlOO.
6-44 General Troubleshooting
ADC/lnterface Section The ADC/Interface Section includes the AlAl Keyboard, AlA RPG (rotary pulse generator), and A3 Interface assemblies. Table 7-l lists signal versus pin numbers for control cable W2. Troubleshooting Using the TAM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7-4 Automatic Fault Isolation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..
Table 7-1.
Table 7-1.
Troubleshooting Using the TAM When using Automatic Fault Isolation, the TAM indicates suspected circuits that need to be manually checked. Use Table 7-2 to locate the manual procedure. Table 7-3 lists assembly test connectors associated with each Manual Probe Troubleshooting test. Figure 7-l illustrates the location of A3’s test connectors. A3 INTERFACE J400 (REVISION CONNECTOR) SK169 J105 Figure 7-1.
Table 7-2.
Table 7-3. TAM Tests Versus A3 Test Connectors Connector A3J105 A3J400 7-6 ADC/lnterface Section Manual Probe Troubleshooting Test Measured Signal Lines Video Input to Interface Video to Rear Panel Video MUX LOG Offset/LOG Expand MS1 MS2 MS3 MSl, MS3 Video Filter Buffer Amp.
Keyboard/RPG Problems Keyboard Interface See function block G of A3 Interface Assembly Schematic Diagram (sheet 3 of 6). A pressed key results in a low on a keyboard sense line (LKSNSO through LKSNS7). This sets the output of NAND gate U607 high, generating KBD/RPG-IRQ. The CPU determines the key pressed by setting only one keyboard scan line (LKSCNO through LKSCN5) low through U602 and reading the keyboard sense lines. 1. If none of the keys or RPG responds, check ribbon cable, AlAlWl.
RPG Interface See function block J of A3 Interface Assembly Schematic Diagram (sheet 3 of 6). U608B latches the RPG direction from the two RPG outputs, RPG-01 and RPG-02. Counterclockwise RPG rotation produces low-going pulses which result in a high output on U608B. Clockwise RPG rotation results in a low output from U608B. U612A provides the edge to trigger one-shot U423B, which generates a 90 ms pulse. This pulse gates U610A for counting of RPG pulses by U606.
Table 7-5. Counter Frequencies A3U606 pin # Nominal Frequency (Hz) 3 4 5 6 11 10 3900 1950 975 488 244 122 Triggering Problems See function block H of A3 Interface Assembly Schematic Diagram (sheet 3 of 6). The 1 MHz ADC clock provides synchronization in FREE RUN and SINGLE triggering. LINE triggering synchronization originates on the A6 Power Supply. Trigger MUX A3U613A selects between FREE RUN, VIDEO, LINE, and EXTERNAL trigger sources. The trigger signal sets the output of the HSCAN latch high.
8. If the voltage changes incorrectly, proceed as follows: a. Check the -10 Vdc reference (A3U409 pin 4). b. While using the front-panel knob to adjust the video trigger level, check for the presence of pulses on A3U409 pin 15 (LDAC2). c. While using the front-panel knob to adjust the video trigger level, check for the presence of pulses on A3U409 pin 16 (LWRCLK). d. Check that pulses are present on U409 pin 6 (IAO). 9.
Flatness Control (RF Gain DACs) See function block M of A3 Interface Assembly Schematic Diagram (sheet 4 of 6). RF Gain DACs control the Al5 assembly’s flatness compensation amplifiers. The RF Gain DACs are arranged so that the output of one DAC is the voltage reference for the other DAC. This results in an RF GAIN voltage which is exponentially proportional to the DAC settings. Each DAC is set to the same value.
A3 Assembly’s Video Circuits Voltages from A3JlOl to A3’s Variable Gain Amplifier correspond (approximately) to on-screen signal levels. (One volt corresponds to the top of the screen and zero volts corresponds to the bottom of the screen.) This is true for both log and linear settings except when the analyzer is in 1 dB/div or 2 dB/div. In these cases the log expand amplifier is selected, and 1 V corresponds to top-screen and 0.8 or 0.9 V corresponds to bottom-screen.
Note The on-screen amplitude level will probably not change as expected, since the video circuitry is assumed to be faulty. 15. Monitor A3TP14 while stepping the reference level from -10 dBm to +30 dBm. If the voltage does not step approximately 100 mV per 10 dB step, refer to “Video MUX” in this chapter. 16. If the Video MUX is working properly, monitor A3TP15 with the oscilloscope and step the reference level from -10 dBm to f30 dBm.
22. Change the reference level from -10 dBm to 0 dBm. The voltage change on A3TP7 should be between 670 mV and 730 mV. If the voltage change is outside of these limits, refer to “Variable Gain Amplifier (VGA)” in this chapter. The gain of the VGA should be 7 &lO%. Log Offset/Log Expand See function block X of A3 Interface Assembly Schematic Diagram (sheet 5 of 6). The log scales are modified using a combination of amplification and digital trace manipulation.
Video MUX See function block U of A3 Interface Assembly Schematic Diagram (sheet 5 of 6). The AUX VIDEO port and the 0 SPAN CAL function are not used. Both Q220 and Q219 should be off at all times. 1. Press (PRESET) and set the HP 8560A controls as follows. C E N T E R F R E Q . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...300 MHz SPAN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . OHz 2.
4. Step the Video BW down to .1 Hz. At each step, the amplitude of the LO feedthrough should decrease. 5. Refer to Table 7-7 and check for correct latch settings for the selected video bandwidth setting. 6. If latch A3U102’s output is not correct, trigger an oscilloscope on LLOGSTB (UlO2 pin 9) and monitor U102 pin 1 and other latch inputs while changing the video bandwidth. 7. If the inputs are incorrect, troubleshoot the analog bus. Correct inputs with bad outputs indicate a faulty U102. 8.
Positive/Negative Peak Detectors See function blocks Y and Z of A3 Interface Assembly Schematic Diagram (sheet 5 of 6). The following information pertains to the positive peak detector and is applicable to troubleshooting the negative peak detector. The positive peak detector consists of an input amplifier (A3U204 and A3Q210) followed by detector diodes (A3CR203 and A3CR204) and hold capacitor A3C217. Output amplifier A3Q206, Q211, and Q212 buffers the hold capacitor.
8. If the reset pulses are absent, troubleshoot the Peak Detector Reset circuitry. 9. If the reset pulses are present, check the gate of Q207. The pulses should be positive-going from -12.7 V to -1.35 V. 10. The peak detector can be made into a unity gain amplifier by shorting the cathode of CR203 to the anode of CR204. If the peak detector functions normally as a unity gain amplifier, suspect Q208 or CR203 or CR204.
1. Press (%?i) on the HP 8560A and set the controls as follows: C E N T E R F R E Q . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...300 MHz SPAN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . OHz SWEEP TIME . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5s DETECTOR MODE . . . ........................................ NORMAL 2.
Table 7-9. Logic Levels at A3U108 iDetector Mode U108 pin 1 U108 pin 15 U108 pin 16 SAMPLE H L H POS PEAK H L L NEG PEAK L H H 5. Set the HP 8560A to the following settings: SPAN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..lMHz SWEEP TIME . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50ms 6.
Variable Gain Amplifier (VGA) See function block AB of A3 Interface Assembly Schematic Diagram (sheet 6 of 6). The VGA provides adjustable gain in the video path. Its nominal gain of 7 can be adjusted 510%. U112 removes dc offset to keep U113 in its monotonic range. (Both U112 and U113 are set to the same value.) The DAC settings cannot be changed from the front panel. Track and Hold See function block AC of A3 Interface Assembly Schematic Diagram (sheet 6 of 6). 1.
A3 Assembly’s ADC Circuits The ADC consists of a 12-bit DAC, 12-bit successive approximation register (SAR), data multiplexers, and data latches. The ADC ASM (algorithmic state machine) controls the ADC. Eight inputs are controlled by the ADC MUX. These include a positive peak detector, negative peak detector, sampled video, scan ramp, YTO error voltage, FC MUX voltages, Cal Oscillator tune voltage, and offset lock error voltage.
ADC Start/Stop Control See function block B of A3 Interface Assembly Schematic Diagram (sheet 2 of 6). The ADC Start/Stop Control determines the start time of all ADC conversions. Multiplexer A3U509 chooses the source of the start signal. Both HSTART-SRC and HBUCKET tell the ASM to start a conversion. 1. Press (ml on the HP 8560A and set the following controls: SPAN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . OHz SWEEP TIME . . . . .
See function block F of A3 Interface Assembly Schematic Diagram (sheet 2 of 6). 1. Press (=I) on the HP 8560A and set the controls as follows: SPAN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0 Hz SWEEP TIME . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..~OS DETECTOR MODE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . SAMPLE 2.
Note Since U512 pin 2 is at a virtual ground (currents are being summed at this node), voltage levels at this point are difficult to interpret. Ramp Counter See function block D of A3 Interface Assembly Schematic Diagram (sheet 2 of 6). The ramp counter is used for non-zero-span sweeps and for zero-span sweep times greater than 30 ms. The analog sweep ramp is compared to the digital ramp counter.
A3 Assembly’s Control Circuits A digital control problem will cause the following three steps to fail. 1. On the HP 8560A, press (-1, ATTEN MAN, 0, a, and (dB. 2. A click should be heard after pressing dB in step 1, unless ATTEN was previously set to 70 dB. 3. Press 0, @, and @. Another click should be heard. If no clicks were heard, but the ATTEN value displayed on the CRT changed, the digital control signals are not operating properly.
14. If any address or data line is low, check the appropriate input of either U405 (data lines) or U406 (address lines). 15. If a data line input is stuck low, check the data bus buffer. If an address line input is stuck low, check A3Wl and the A2 Controller assembly. 16. If the appropriate input is high or toggling between high and low, suspect a failure in either U405 (data lines) or U406 (address lines). 17. Remove jumpers.
13. Monitor A3U401 pin 9 (LV_STB) with an oscilloscope or logic probe. This is the strobe for the A4 Log Amplifier/Cal Oscillator assembly. 14. Press [w) and check that pulses occur when toggling between LINEAR and LOG DB/DIV . Interface Strobe Select See function block K of A3 Interface Assembly Schematic Diagram (sheet 3 of 6). Interface strobe select generates the various strobes used by circuits on the A3 Interface Assembly.
8 IF Section The IF Section contains the A4 Log Amplifier/Cal Oscillator and A5 IF assemblies. Troubleshooting Using the TAM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8-3 Troubleshooting A4 Log Amplifier with the TAM . . . . . . . . . . . . . ;. . . . . . . . . . . . . . . . . . . . . . .8-4 Troubleshooting A5 with the TAM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
300 Hz to 3 kHz Resolution Bandwidth Out of Specification . . . . . . . . . . . . . . . . . . . . . . . . . 8-36 Low-Pass Filter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 8-40 Sweep Generator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8-40 AM/FM Demodulation, Audio Amplifier, and Speaker . . . . . . . . . . . . . . . . . .
Note Because the Cal Oscillator circuitry on the A4 assembly is such an integral part of the IF adjustment, always check this assembly first, before checking the rest of the IF Section. A faulty Cal Oscillator can cause many apparent “faults” in the rest of the IF Section. Troubleshooting Using the TAM When using Automatic Fault Isolation, the TAM indicates suspected circuits that need to be manually checked. Use Table 8-l to locate the manual procedure.
Table 8-1.
Table 8-2.
Table 8-2.
~5 OdBm 10.7 MHz F ADJ OFF .-mm----10 7 MHz / I CAL OSC i L ---------I +lV D C IF ADJ OFF W54 DISCONNECTED i J3 ]+I- LOG p- I P [_: I I I I I w54 I 34 ,‘-, I I A i2 LAM/FM - DEMOD (RED) * WITH COUNTER ON BURSTS OF 5.35 MHz A P P R O X 1 0 mSEC 5 “P-P I i LINEAR J u I I I J 5 w53 (-‘, I l& ( B R O W N ) Jb w55 ! I I,b------------------A4 LOG AMP/CAL OSC ASSEMBLY ; J6 f-t !+A! ( W H I T E / ) BLUE) I w27 A SK171 (ORANGE) Figure 8-2.
3. Set the other spectrum analyzer controls as follows: SPAN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...5 MHz REFERENCE LEVEL . . . . . . . . . . . . . . . . , . . . . . . . . . . . . . . . . . . . . . . . . +lO dBm CENTERFREQUENCY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10.7MHz 4. On the spectrum analyzer, set the Cal Oscillator to 10.7 MHz by selecting Fixed Tuned to 10.7 MHz . 5.
Table 8-3. Sweep Width Settings Sweep Width Sweep Time RES BW RANGE MA1 MAO Adjusted 20 kHz 10 kHz 4 kHz 2 kHz 5 ms 10 ms 30 ms 60 ms 10 kHz 3 kHz 1 kHz 300 Hz $5 +5 +5 +5 0V 0V V 0 V +5v V V +5 V 0 V V +5 V +5 V Automatic IF Adjustment The spectrum analyzer performs an automatic adjustment of the IF Section whenever needed. The Cal Oscillator on the A4 assembly provides a stimulus signal which is routed through the IF during the retrace period.
Parameters Adjusted The following IF parameters are adjusted in the sequence listed: 1. Amplitude A. Video Offsets: analog (using A4 Log Amplifier video offset DAC) and digital (applying stored constant to all readings) 1. Linear Scale Offset 2. Log Scale Offset a. Wideband and Narrowband modes. b. 0 to 60 dB range in 10 dB steps. c. 10 dB/DIV and 2 dB/DIV (log expand) modes. B. Step Gains (A5 IF Assembly) 1. First Step Gain for 16 different DAC settings. 2. Second Step Gain for 16 different DAC settings.
B. 10 kHz resolution bandwidth 1. Center frequency of LC tank that loads the crystal 2. Symmetry adjustment to cancel crystal case capacitance. 3. Bandwidth C. 3 kHz resolution bandwidth: center frequency of LC tank and bandwidth of resolution bandwidth D. 1 kHz resolution bandwidth: bandwidth E. 300 Hz resolution bandwidth: bandwidth F. Gain of all resolution bandwidth relative to the 300 kHz RES BW. 4. Digital Bandwidths (10 Hz through 100 Hz) A.
Performance Test Failures Failures in IF-Section-related performance tests may be investigated using the following information. IF Gain Uncertainty Performance Test Failure of this performance test indicates a possible problem with the spectrum analyzer IF gain circuits. Assuming no major IF problems causing IF adjustment errors, IF gain problems in the first 50 dB of IF gain (REF LVLs of 0 dBm to -50 dBm with 10 dB ATTEN) are a result of faults on the A5 IF Assembly.
4. Set the signal generator controls as follows: Amplitude . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . +lO dBm Frequency . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10.7MHz 5. Simultaneously decrease the signal generator output and the spectrum analyzer REF LVL in 10 dB steps. The signal displayed by the spectrum analyzer should remain at the reference level for each step.
A4 Assembly’s Log Amplifier Circuits The Log Amplifier on the A4 assembly performs several functions. It provides log and linear paths converting the 10.7 MHz’IF signal to video. In addition it also provides offset circuitry, AM/FM demodulator circuitry, a frequency counter output, and down conversion of the 10.7 MHz IF to 4.8 KHz for use by the digital IF. The log amp results are realized by using a wide dynamic range linear detector followed by a video log amp.
10. If log fidelity is poor near the bottom of the screen or the 1 MHz resolution bandwidth is narrow, a fault might exist in the wide/narrow filter switch. Refer to function block G of A4 Log Amplifier Schematic Diagram in the HP 856UA/6lB/63A Spectrum Analyzer Component Level Information binder. Check this switch as follows: a. Monitor voltages on A4U302 pins 1 and 7 while changing the spectrum analyzer resolution bandwidth from 100 kHz to 300 kHz. b.
Video Offset Refer to function block P of A4 Log Amplifier Schematic Diagram (sheet 3 of 4) in the HP 856OA/6lB/63A Spectrum Analyzer Component Level Information binder. The circuit provides a programmable video offset, with a step size of 5 mV, from -300 mV to +900 mV. 1. On the spectrum analyzer, press (m), (SPAN), ZERO SPAN, (-1, 1 IGHz), [AMPLITUDE), 50 (--dBm). Turn the IF auto cal off. 2. Disconnect W27 (coax 3) from A4J3 and connect a signal generator to A4J3. 3.
9. Reconnect cables W54 to A4J6 and W52 to A4J8. Frequency Counter Prescaler/Conditioner Refer to function block Q of A4 Log Amplifier Schematic Diagram (sheet 4 of 4) in the HP 856OA/61B/63A Spectrum Analyzer Component Level Information binder. The Frequency Counter Prescaler/Conditioner divides the frequency by two, and then attenuates it. The circuit consists of frequency divider (U703A) and an output attenuator. The frequency divider turns on only when the instrument is counting.
Caution If a dc block is not used, damage to the HP 8566A/B results. The HP 8566A/B and many other spectrum analyzers have dc-coupled inputs and cannot tolerate dc voltages on their inputs. 6. Set the HP 8566A/B to single trigger and press TRACE A [CLEAR-WRITE]. Trigger a sweep of the HP 8566A/B and the signal generator simultaneously. The HP 8566A/B shows the passband of the 4.8 kHz IF filters. The 3 dB bandwidth of the filters should be 1.2 kHz.
f. Press (A--B)A), (FREQUENCY SPAN), 2 @). The response should now be displayed right-side up. Ignore any “wings” to the left and right of the passband. g. The amplitude at 4.5 kHz and 5.1 kHz relative to 4.8 kHz should be 0 to -2.5 dB.. 10.6952 MHz VCXO Refer to function block E of A4 Log Amplifier Schematic Diagram (sheet 2 of 4) in the HP 856OA/61B/63A Spectrum Analyzer Component Level Information binder. The purpose of the 10.
Synchronous Detector A wide dynamic range linear detector is realized by the Limiter (block G), the Isolation Amplifier (block H), the LO Amplifier (block I), and the Detector/Mixer (block J). The combination of these circuits form what is commonly known as a synchronous detector. The input signal is split between two paths.
Sum and difference frequencies are produced in the Detector/Mixer. The difference frequency produces video (dc to approximately 3 MHz), since the two signals are at the same frequency. During digital resolution bandwidths the two signals are separated by 4.8 kHz. Log Offset/Gain Compensation Refer to function blocks L and M of A4 Log Amplifier Schematic Diagram (sheet 3 of 4) in the HP 856OA/61B/63A Spectrum Analyzer Component Level Information binder.
A5 IF Section The input switch connects the IF to either the A4 Cal Oscillator or the 10.7 MHz IF output from the Al5 RF assembly. The Automatic IF Adjustment uses the A4 Cal Oscillator at instrument turn-on and between sweeps to align the IF filters and step-gain amplifiers. During sweeps the input switch selects the 10.7, MHz IF output from A15. The LC filters are variable-bandwidth filters that provide resolution bandwidths from 30 kHz to 2 MHz.
Caution Do not short power-supply voltages to ground. The analyzer power-supply current limiting cannot protect the resistors in series with the power supply. Note Some transistors have collectors connected to the case. Electrical connection of the case to the collector might not be reliable, making collector voltage measurements on the transistor case unreliable. IF Signature 1. Disconnect W27 (coax 3) from A5J5. 2. Connect the source connection of a 3 dB power splitter to A5J5.
3. Set the HP 8566A/B controls as follows: REFERENCE LEVEL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . j-10 dBm CENTERFREQUENCY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10.7MHz SPAN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . OHz RESOLUTION BANDWIDTH . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 300 kHz VIDEO BANDWIDTH . . . . . . . .
REF 5 1 0 . 0 dBm ATTEN 2 0 I I dB dB/ SAMPLE I I CENTER 10.700 000 MHz R E S B W 3 0 0 kHz I V B W 3 0 0 kHz I I I SPAN 0 Hz S W P 5 0 0 msec SK174 Figure 8-5. Detailed IF Adjust Signature (2) REF 1 0 . 0 / 1 0 ATTEN 2 dBm 0 dB 1 I dB/ SAMPLE CENTER 10.700 000 MHz R E S B W 3 0 0 kHz V B W 3 0 0 kHz SPAN 0 H S W P 1 . 4 set SK175 Figure 8-8.
REF 1 0 1 0 . 0 dBm ATTEN 2 0 dB dB,’ SAMPLE CENTER 1 0 . 7 0 0 0 0 0 MHz R E S B W 3 0 0 kHz VBW 1 kHz SWP SPAN 0 Hz 1 . 4 0 set SK176 Figure 8-7. Detailed IF Adjust Signature (4) REF 1 0 .I0 dBm ATTEN 2 0 dB dB/ SAMPLE CENTER r 1 0 . 7 0 0 0 0 0 MHz R E S B W 3 0 0 kHr VBW 1 kHz SWP SPAN 0 H z 2 . 0 0 set SK177 Figure 8-8.
Common IF Signature Problems n n Region A of Figure 8-4 is noisy: Suspect the first LC pole. Region B of Figure 8-4 is flat: Suspect the third step-gain stage, the fine attenuator, or the fourth LC-pole output amplifier. H Region C of Figure 8-4 has no 15 dB step: Suspect the reference 15 dB attenuator. n Region D of Figure 8-4 is flat: Suspect the second step-gain stage.
REF 5 1 0 . 0 dBm ATTEN 2 0 dB/ SAMPLE CENTER 10.700 000 MHz R E S B W 3 0 0 kHz I t - S P A N 1Q Hz S W P 5 0 0 set V B W 3 0 0 kHz SK179 Figure 8-10. Noise with Correct Shape RE F 5 1 0 . 0 dBm ATTEN 2 0 dl? dB/ SAMPLE CENTER 1 0 . 7 0 0 0 0 0 MHz R E S BW 3 0 0 kHz VBW 3 0 0 kHz SWP SPAN 0 Hz 5 0 0 set SK180 Figure 8-11.
RE F/ 5 I”.; dBmi ATTEN 20 dB dB,’ SAMPLE CENTER 1 I 1 0 . 7 0 0 0 0 0 MHz R E S B W 3 0 0 kHz I I I V B W 3 0 0 kHz SPAN 0 Hz S W P 5 0 0 set SK181 Figure 8-12. Region B Amplitude Offset 1 MHz Resolution Bandwidth Problems Check the crystal shorting switches as follows: 1. On the spectrum analyzer, press [PRESET) and set the controls as follows: RES BW . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . l M H z SPAN . . . . . . .
*ATTEN l0dB RL OdBm lOdB/ 1 I C E N T E R 300.0000MHz *RBW 1.0MHz / I I I 1 1 I S P A N 5 0 0 0kHz V B W 1.0MHz SWP 50ms SK182 Figure 8-13. Faulty Crystal Short *ATTEN 1 0 d B R L 0dBm 10dB,’ A C E N T E R 300.0000MHz cRBW 1.0MHz V B W 1 0MHz S P A N 3 000MHz SWP 50ms SK183 Figure 8-14.
30 kHz Resolution Bandwidth Problems Shape factor too high: Shape factor is the ratio of the 60 dB bandwidth to the 3 dB bandwidth. Shape factor should be less than 15:l. If one of the LC poles malfunctions, the shape factor may be the only indication of the failure. Isolate the non-functioning pole with the IF signature. Region E of Figure 8-8 illustrates the four LC- pole adjustments. Take several signatures to examine the LC-pole adjustments.
ATTEN 1 0 d B RL OdBm 10dB,’ BIRoKEN C E N T E R 300.0000MHz *RBW 3.0kHz JSYMME~~TRY V B W 3.0kHr 1 S P A N 1 0 0 0kHz SWP 70ms SK184 Figure 8-15. Faulty Crystal Symmetry Step Gains Refer to function blocks B, H, and I of A5 IF Filter Schematic Diagram (sheets 1 of 3 and 2 of 3) in the HP 856OA/61B/63A Spectrum Analyzer Component Level Information binder. I. On the spectrum analyzer, press (-1, (SPAN), ZERO SPAN , (w), 1 IGHz). 2. Press (CAL), IF ADJ OFF. 3.
A4 Assembly’s Cal Oscillator Circuit The Cal Oscillator on the A4 assembly supplies the stimulus signal for Automatic IF adjustments. Normally, the oscillator operates only during retrace (for a few milliseconds) to adjust part of the IF. (All IF parameters are to be readjusted about every 5 minutes.) With continuous IF adjust on, a group of IF parameters are adjusted during each retrace period (non-disruptive). If continuous IF adjust is off, the most recent IF calibration data is used.
Cal Oscillator Unlock at Beginning of IF Adjust 1. Turn the spectrum analyzer luNE) switch off and then on. The words IF ADJUST STATUS appear on the display 10 seconds after the instrument is turned on (assuming the rest of the instrument is working correctly). Immediately observe the lower right corner of the display for error messages. If the message ERR 499 CAL UNLK appears (before errors ERR 561, 562 and 565), the cal oscillator is unable to phase-lock.
e. If the DVM reading is outside the range in step c but inside the range in step d, suspect one of the filter-reactive components. 8. If the ALC loop is working correctly (A4J9 pin 4 within the test tolerances given), then either the output attenuator is defective, or A4U810 pin 6 (in ALC loop integrator) is outside of its +3 to +6 Vdc range. 9. Reconnect W52 (coax 9) to A5J4. 300 Hz to 3 kHz Resolution Bandwidth Out of Specification 1.
R E F - 4 3 . 0 dBm ATTEN 1 0 1 I dB 1 dB,’ I L CENTER 1 0 . 8 0 0 0 0 0 MHz R E S B W 1 0 0 kHz VBW I 10 I / SWP kHz I I SPAN 0 Hz 5 0 . 0 msec SK186 Figure 8-17. Output Waveform, 3 kHz Resolution Bandwidth FR?EF E F - - 44 33 .. 0 dBm dBm ATTEN 1 0 dB 1 dB/ \ CENTER 1 0 . 7 1 0 0 0 0 MHz R E S B W 1 0 kHz \ \ VBW 1 kHz \ \ SWP SPAN 0 Hz 2 0 0 msec SK187 Figure 8-18.
R E F 1 - 4 3 . 0 ATTEN 1 dBm 0 dB dB/ I I I \ I L I I i \, I \ \ -& \ L- \ ‘- \, - ‘\ L \ - \ ~A& \ I I CENTER L I I 1 0 . 7 1 0 0 0 0 MHz RES B W 1 0 kHz I I VBW 1 I I I kHz SWP I I SPAN 0 Hz 2 0 0 msec SK188 Figure 8-19. Output Waveform, 300 Hz Resolution Bandwidth REF 1 - 4 3 . 0 dBm ATTEN 10 dB dB/ I CENTER I I 1 0 . 7 1 0 0 0 0 MHz R E S B W 1 0 kHz /I VBW II 1 kHz I I SWP I SPAN 0 Hz 2 0 0 msec SK189 Figure 8-20.
Low-Pass Filter Refer to function block AB of A4 Cal Oscillator Schematic Diagram in the HP 856OA/61B/63A Spectrum Analyzer Component Level Information binder. 1. Connect a DVM positive probe to A4J9 pin 4. 2. On the spectrum analyzer, press ICAL). 3. Press FULL IF ADJUST. Observe the DVM reading between the displayed messages IF ADJUST STATUS: 300 kHz RBW and IF ADJUST STATUS: 3 kHz RBW. During this time period, the voltage should be within a 2 to 10 Vdc range. 4.
3. Adjust the spectrum analyzer reference level and center frequency to display the 400 Hz modulation frequency eight divisions peak-to-peak. 4. On the spectrum analyzer press (mCTRL), AM/FM DEMOD , AM DEMOD ON, and set the sweep time to 5 seconds. 5. Vary the volume and listen for the variation in speaker output level. Clipping is normal on the highest settings. 6. If the audio is not working correctly monitor the signal at A4U704 pin 3 with an oscilloscope.
8-42 IF Section
9 Controller Section The Controller Section includes the A2 Controller Assembly, A19 HP-IB Assembly, and BTl Battery. The presence of a display (graticule and annotation) verifies that most of A2 Controller Assembly is operating properly. Troubleshooting Using the TAM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9-l Blank Display . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Table 9-1. TAM Tests Versus Test Connectors Connector Manual Probe Troubleshooting Test A2Jll ADC/MUX Test DAC Test A2J201 10 Volt Reference Test Switch Drive Test Buffered X & Y DAC Outputs X Line Gen Test Y Line Gen Test Intensity Offset Output A2J202 Revision X, Y, & Z Output Offset Measured Signal Lines MSl, MS3 through MS6, MS8 MS2, MS7, OS1 MS4 MS8 MS2, MS7 MS6 MS1 MS3 MS1 MS3, MS4, MS7 X Output Amplifier Y Output Amplifier Blanking Test Focus DAC Test MS3 MS7 MS8 MS2 Blank Display .
A2 CONTROLLER (T AM TEST CONNECTOR) SPi7 Figure 9-1. A2 Test Connectors 10. Press SOFT KEY #4. The results will be sent to the printer. 11. If a failure is indicated in any of these tests, the fault lies on the A2 Controller assembly. To obtain more information: a. Press the down arrow key one less time than the test number. (For example, press it twice for the third test on the list.) b. Press SOFT KEY t3 , then SOFT KEY 64, and when the printout is complete, SOFT KEY #6. 12.
Digital Signature Analysis (DSA) Digital Signature Analysis (DSA) places microprocessor, A2U1, in a simplified known state. This simplified state consists of placing a one-word instruction, MOVE QUICK, (0111 XX10XXXXXXXO) on the data bus. The microprocessor cycles through its address range continually reading the instruction. Perform the following DSA procedure to test the operation of microprocessor, A2Ul: 1. Set the HP 8560A’s LINE switch off. 2.
5. Compare the signals at the following test points with those illustrated in Figure 9-2. X POS: Y POS: Z OUT: BLANKING: Note A2J202 pin 14 A2J202 pin 3 A2J201 pin 3 A2J202 pin 15 Waveforms displayed on an analog scope may show considerably more spikes. This is normal and is due to the wider displayed bandwidth. 6. Troubleshoot the circuits associated with any bad waveforms. 3 . 0 0 x POS Y POS z POS V/di v 0 . 0 0 v 1 . 0 0 ms/dlv 0 . 0 0 0 s t B L A N K I biG t SK191 Figure 9-2.
4. Compare the blanking-circuit input signals at the following test points with those illustrated in Figure 9-3. BLANKING: BLANK: VECTOR: J202 U214 U214 U213 pin pin pin pin 15 12 11 13 5. The waveforms in Figure 9-3 must match the timing of the vectors being drawn. To do this, U215B is used to adjust the leading edge, and U215A is used to adjust the trailing edge. The first six horizontal divisions show the line drawing mode where the VECTOR pulses are 6 ps apart.
4 . 0 0 u213-13 1 V/div nr 2 . 5 0 V I L 2 . 0 us/div 9 6 . 0 0 u s u BLANK I NG //I II SK193 Figure 9-4. Expanded Blanking Waveforms Display Jumbled or Trace Off Screen See function blocks D and I of A2 Controller Schematic Diagram (sheet 1 of 4) in the Component-Level Information binder. The two line generators are identical circuits, so the following steps apply to both; references will be to the X generator with Y references in parentheses. 1.
1 0 . 0 V/div 0 0 0 v 2 0 0 us/div 0.000 s I NTEGRATE SAMPLE LCHAR VECTOR I I SK194 Figure 9-5. Switch Driver Waveform LCHAR 7. All of the DAC inputs should change state two or more times within a 5 ms window. If one or more DAC bits are not working correctly, this will effect the entire display, but especially in the diagonal lines that go from lower left to upper right. When these lines are drawn, both the X and Y DACs are stepped one count at a time.
13. Figure 9-8 illustrates the waveforms of properly working line generators. Whenever there is a pulse on TPl or TP2, the appropriate integrator (U201B or U203B) generates a ramp (the output vector) which feeds back to U201A (U203A) and shows on its output. 5 . 0 V/div 0 . 0 0 v 1 . 0 0 ms/div 0 000 s U201A-1 TP2 U203A-1 TPI SK195 Figure 9-6. Distorted X/Y Line Generator Waveforms 5 . 0 V/div 0 . 0 0 v 2 0 0 us/div 0 . 0 0 0 s U201A-1 TP2 U203A- 1 TPl SK196 Figure 9-7.
a 0 0 v/dIv 0 . 0 0 v 1 0 . 0 us/div 0 . 0 0 0 s U201A-1 TP2 U203A- 1 TPI SK197 Figure 9-8. Normal X/Y Line Generator Waveforms Intensity 1. The length of the vector being drawn can effect intensity (U210A, U21OC, and U2lOD). Refer to “Long Lines Dimmer Than Short Lines” in this chapter. 2. Short A2U207 pin 2 to pin 7. If the display does not brighten, troubleshoot LBRIGHT switch, U207B. This switch intensifies trace A and active softkeys. 3. Short A2U207 pin 2 to pin 3.
Long Lines Dimmer Than Short Lines See function block M of A2 Controller Schematic Diagram (sheet 1 of 4) in the HP 856OA/61B/63A Spectrum Analyzer Component Level Information. The Z Output function block contains the absolute value circuits which determine the intensity of vectors drawn on the display. The vector length is approximated by the sum of the X length and Y length. The voltage corresponding to the X length, AX, is converted to current by R274.
9. The waveforms should look like those illustrated in Figure 9-10. If the waveform at J201 pin 14 is bad, troubleshoot the Y Line Generator (function block I of A2 Controller Schematic, sheet 1 of 4 in the Component-Level Information binder). 10. If the waveform at U210D pin 14 is bad, troubleshoot the Z Output circuit (function block M of A2 Controller Schematic, sheet 1 of 4). 11. Remove the jumpers. 1 0 . 0 V,‘dlv 0 . 0 0 v 1 . 0 0 ms/div 0 . 0 0 0 s J201-14 U210D-14 SK199 Figure 9-10.
6. In Figure 9-11, there is no synchronization between DEFl and the video patterns X POS and Y POS when DEFl is TTL high. The Y POS level when DEFl is low is the Video In level. 5 . 0 0 V/div 0 . 0 0 v 5 . 0 ms/div 0 . 0 0 0 s DEF 1 x POS Y POS SK1 100 Figure 9-11. DEFI Synchronization Frequency-Count Marker Problems The FREQ COUNT function works by dividing the 10.
Frequency Counter See function block 2 of A2 Controller Schematic Diagram (sheet 4 of 4) in the Component-Level Information binder. The frequency counter counts the frequency of the last IF and provides accurate timing signals for digital zero-spans. The circuit also provides timing signals to the A3 Interface assembly’s ADC (Analog to Digital Converter). The nominal input frequency is 5.35 MHz (10.7 MHz divided by 2). The circuit’s frequency reference is the 10 MHz reference from the Al5 RF assembly.
1. Disconnect W22 from A2J8. 2. If a 10 MHz, TTL-level signal is not present at the end of W22 continue with step 3. If a 10 MHz signal is present at W22, proceed as follows: a. Reconnect W22 to A2J8. b. Set the HP 8560A to the following settings: SPAN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..Zero Span SWEEP TIME . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20ms c.
Keyboard Problems If the analyzer does not respond to keys being pressed or the knob being rotated, the fault could be either on the A3 Interface assembly or the A2 Controller assembly. To isolate the A2 Controller assembly, use the following procedure. This procedure tests the analyzer response over HP-IB and the keyboard/RPG interrupt request signal. 1. Enter and run the following BASIC program.
10 Synthesizer Section The Synthesizer Section includes the A7 First LO Distribution Amplifier, All YTO, and parts of the Al4 Frequency Control and Al5 RF assemblies. Simplified and detailed block diagrams for each assembly are located at the end of this chapter. Page Confirming a Faulty Synthesizer Section . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-2 Troubleshooting Test Setup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Caution Using an active probe, such as an HP 85024A, with a spectrum analyzer is recommended for troubleshooting the RF circuitry. If an HP 1120A Active Probe is being used with a spectrum analyzer, such as the HP 8566A/B, HP 8569A/B and the HP 8562A/B, having dc coupled inputs, either set the active probe for an ac coupled output or use a dc blocking capacitor (HP 11240B) b e t ween the active probe and the spectrum-analyzer input.
2. Set the HP 8560A to the following settings: SPAN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . OHz C E N T E R F R E Q . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .389.5MHz CF STEP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.5 MHz 3. Use the step keys to tune the CENTER FREQ to the values listed in Table 10-l. 4.
10. Set the HP 8560A to the following settings: CENTER FREQ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .300 MHz SPAN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..lOOMHz 11. If the 1st LO is present, a signal should be displayed at about -10 dBm (approximately f20 MHz from the center frequency). If no signal is displayed and ERR 334 LO AMPL is not present, troubleshoot the A7 LODA.
SYNTHESIZED SWEEPER ADAPTER Q S P E C T R U M A N ,A L Y Z E R A D A P T E R jj DIGITAL ‘y.ln1111 VOLTMETER A14>501 A14J17 P I N 1 A14‘ FREO CONTROL SK1 101 Figure 10-l. YTO Loop Test Setup 18. Disconnect W34 from A15A2Jl and disconnect W32 from A15JlOl. 19. Connect a frequency counter to A15JlOl. Connect a high-frequency test cable from an HP 8340A/B Synthesized Sweeper to A15A2Jl. See Figure 10-2. 20.
BNC CABLE FREQUENCY COUNTER S&Wⅈ I 2 ED I FREOUENCY STANDARD EXT TEST CABLE SMA C A B L E A I 5’J 1 0 1 AdA Jl SK1102 Figure 10-2. Sampler and Sampling Oscillator Test Setup 24. At each combination, the frequency counter should measure a sampler IF of 100.2 MHz &500 Hz. (The Offset PLL’s sampling oscillator tunes to the frequencies listed in the table.) If the frequency counter does not read a sampler IF of 100.2 MHz, suspect the Al5 RF Assembly. 25. Reconnect W34 to A15A2Jl and W32 to A15JlOl.
Table 10-2. Sampling Oscillator Test Frequencies HP 8560A HP 8340A Frequency of Offset PLL’s Zenter Frequency (MHz) CW Frequency (MHz) Sampling Oscillator (MHz) 389.5 464.5 4300.2 4337.7 4360.2 4375.2 479.5 4390.2 502.0 4412.7 4420.2 4450.2 4480.2 4487.7 4510.2 4525.2 4540.2 4562.7 4570.2 427.0 449.5 509.5 539.5 569.5 577.0 599.5 614.5 629.5 652.0 659.5 280.0 282.5 284.0 285.0 286.0 287.5 288.0 290.0 292.0 292.5 294.0 295.0 296.0 297.5 298.
n To display the nominal YTO’s frequency, press (CAL), MORE, FREQ DIAGNOSE, LO FREQ . Table 10-3.
Table 10-4.
Table 10-4.
Table 10-5. TAM Tests versus Test Connectors (1 of 2) Connector Manual Probe Troubleshooting Test Measured Signal Line, A14J 15 Sweep Generator Span Attenuator DAC Span Attenuator Switches Sweep + Tune Mult Input Amp Sweep + Tune Mult Input Switches VCO Sweep Driver A14J 16 Al4J17 FAV Generator FAV Gen 0.
Table 10-5.
General PLL Troubleshooting The Synthesizer Section relies heavily on Phase-Lock Loops (PLL). Typically, faulty PLL’s are either locked at the wrong frequency or unlocked. The information below applies to troubleshooting these two classes of problems on a generalized PLL. PLL Locked at Wrong Frequency Numbers in the following text identify items in Figure 10-4. n Any frequency errors at reference (1) will be multiplied by N/M on the PLL’s output.
1. The loop integrator’s output voltage (1) should be attempting to tune the oscillator to the correct frequency. a. The voltage at (1) should increase as the frequency increases on the following PLLs: YTO PLL Reference PLL Sampler PLL A14J17 pin 1 (YTO LOOP ERROR) A15J502 pin 3 (LO3 ERR) A15J200 pin 13 (OFL ERR) b.
Frequency Span Accuracy Problems The HP 8560A employs lock-and-roll tuning to sweep the 1st LO. The 1st LO is locked to the start frequency immediately after the previous sweep has been completed. The 1st LO is then unlocked, and, when a trigger signal is detected, the 1st LO sweeps (rolls). When there is a considerable delay between the end of one sweep and the beginning of the next, the actual 1st LO start frequency may differ from the locked start frequency.
3. Use the following equation to determine the first-LO span used. First LO Span = Display’s Span Setting Current Band’s Harmonic Mixing Number 4. Refer to Table 10-6 to determine the circuit associated with the span. Confirming Span Problems 1. If all first-LO spans or only first-LO spans of 1.01 MHz or above are affected, perform the YTO Adjustment procedure in Chapter 2. a. On the HP 8560A press (CAL), REALIGN LO & IF, and retest all spans. b.
YTO FM Coil Span Problems (LO Spans 1.01 MHz to 20 MHz) In YTO FM Coil spans, the YTO loop is locked and then opened while the sweep ramp is summed into the FM coil. FM spans are adjusted by changing the sensitivity of the FM coil driver. 1. Perform the YTO Adjustment procedure in Chapter 2. If the YTO adjustments cannot be performed, continue with this procedure. 2. Set the HP 8560A to the following settings: C E N T E R F R E Q . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
13. The voltage at A14U332 pin 2 should be approximately 19% of the voltage at A14523 pin 2. 14. If the 1st LO frequency did not change in step 12, set the HP 8560A’s (LINE) switch OFF and disconnect WlO from A14J3. 15. Place a jumper between A14J3 pins 9 and 10 and set the (LINE) switch ON. 16. On the HP 8560A press (m), STATE, STATE 0. 17. Repeat steps 6 through 13. 18.
3. If A14J17 pin 1 does not appear to be correct, verify that the sweep ramp is reaching the Main/FM/VCO Sweep Switch as follows: Change the oscilloscope’s amplitude scale to 1.25 V/d’iv and monitor the A14J15 pin 14. The waveform should be a 0 V to -10 V sweep of 50 ms duration. See Figure 10-7. Check for a 0 V to -10 V ramp at A14J15 pin 13. Refer to function block H of Al4 Frequency Control Schematic (sheet 2 of 5). Check that state of the Main/FM/VCO S weep Switches as indicated in Table 10-9.
4. Set the HP 8560A to the following settings to open U324A and close U418C. This inverts the waveform at A14J15 pin 13. START FREQ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 678.8 MHz SPAN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..lMHz 5. The waveform at A14J15 pin 13 should be a ramp from 0 V to -10 V. 6. Set the HP 8560A to the following settings: C E N T E R F R E Q . . . . . . . . .
First LO Span Problems (All Spans) 1. Set the HP 8560A to the following settings: C E N T E R F R E Q . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...300 MHz SPAN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..lMHz RES BW . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..lMHz VIDEO BW . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
17. Set the HP 8560A’s sweep time to 100 ms. The voltage at 518 pin 4 should measure approximately -4.21 Vdc. 18. Set the HP 8560A’s sweep time to 200 ms. The voltage at 518 pin 4 should measure approximately -2.1 Vdc. 19. The analog switches and comparators should be set as listed in Table 10-10. 20. Check that U312D opens when the sweep time is set to 2 seconds. 21. Check that U312B and U312C close when the sweep time is set to 20 seconds. Table 10-10.
Unlocked YTO PLL Operation The All YTO is locked to two other oscillators, the Roller PLL’s Main Oscillator and the Offset PLL’s Sampling Oscillator. For LO spans of 1.01 MHz and above, either the FM or Main Coil of the YTO is swept directly. For LO spans of 1 MHz and below, the Roller PLL’s Main Oscillator is swept. The Sampling Oscillator remains fixed-tuned during all sweeps. The output of All YTO feeds through the A7 LO Distribution Amplifier (LODA) to the A15A2 Sampler.
negative Sampler IF’s, the Main Roller Oscillator must sweep from a higher frequency to a lower frequency. This is necessary since an increasing YTO frequency decreases the Sampler IF for negative Sampler IF’s. The opposite is true for positive Sampler IF’s, so in these cases, the Main. Roller Oscillator sweeps more conventionally from a lower frequency to a higher frequency.
Table 10-l 1.
4. Measure the YTO frequency at the front-panel’s 1ST LO OUTPUT jack and record below: YTO Frequency (measured) = ----------------------I MHz ’ Al4 FREQUENCY CONTROL ASSEMBLY / ! MAIN COIL TUNING I FM COIL TUNING I -T I --- I J304 ROLLER TEST A P P R O X - 3 0 dBm 63 TO 105 5 MHz MAIN ROLLER FREO I SAMPLER I I - - - -s--- --- -15 T O OdBm 63 TO 105 5 MHz W H E N LOCKED,SAME AS MAIN ROLLER FREQ SK1 108 Figure 10-8. Troubleshooting an Unlocked YTO PLL 5.
8. If the YTO Frequency Error recorded in step 5 is less than 10 MHz, do the following: a. Measure the frequency at A14J304. The frequency should be equal to the frequency recorded in step 6. If not, refer to “Unlocked Roller Oscillator PLL” in this chapter. b. Measure the input and output levels of the A15A2 Sampler. If the sampler appears defective, check the LO drive to the sampler as described in “Sampler and Sampler IF.” c. Refer to steps 35 through 49 below. 9.
Table 10-12. YTO Frequency Errors with A14J23 on Pins 2 and 3 ( I - 1 0 4 to -93 MHz - 9 3 to -73 MHz - 7 3 to -65 MHz +65 to +73 MHz +73 to +93 MHz +93to $104 MHz YTO Frequency Error (with 523 on pins 2 and 3) -10 -20 -30 -10 -20 -30 to to to to to to Gain of U328B +30 MHz +20 MHz +10 MHz +30 MHz +20 MHz +lO MHz -1 -1 -1 +1 $1 +1 10. The 1st LO’s pretuned frequency must be sufficiently accurate for the YTO loop to acquire lock. The 1st LO’s amplitude must be sufficient to drive the A15A2 Sampler.
22. Place jumper A14J23 in the NORMAL position and reconnect W34 to A15A2Jl. 23. Set the HP 8560A to the following settings: CENTER FREQ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .300 MHz SPAN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . OHz 24. Place jumper A14J23 in the TEST position. 25. Disconnect W32 from A15JlOl.
33. If the voltage monitored in step 23 is correct with a 0 dBm output but not with -15 dBm output, suspect A14U201 or A14U202. If the voltage does not change, check the YTO PLL Loop’s divide-by-two circuits as follows: Set the signal generator for an 80 MHz output. Measure A14U203 pin 2 with an active probe and a spectrum analyzer. The signal should be approximately 0 dBm (ECL levels) and 47.35 MHz (94.7 MHz Main Roller Frequency divided by two).
41. The Main Coil Coarse and Fine DACs correct any initial pretune errors in the YTO main coil. The DACs adjust the FM-coil current to zero before any sweep begins. Refer to function block I of Al4 Frequency Control Schematic (sheet 2 of 5). 42. Set the HP 8560A to the settings listed below. These set both DACs to 128 (the DAC setting range is 0 to 255). C E N T E R F R E Q . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...300 MHz SPAN . . . . . . . . . . . . . . . . .
Unlocked Roller Oscillator PLL Operation The Roller Oscillator is used in the HP 8560A as a reference for the 1st LO phase-lock loop. It provides the 25 Hz start-frequency resolution for the 1st LO, and is the means by which the 1st LO is swept in LO spans of 1 MHz or less (Roller spans).
3. If the Roller Oscillator measures a stable 94.7 MHz, the Roller Oscillator PLLs are probably locked. 4. If the Roller Oscillator is off-frequency or unstable and no error message is displayed, check Roller MUX U305, Roller MUX Amplifier U328, and MUX Gain Control Switch U328B. Refer to function block AG of Al4 Frequency Control Schematic (sheet 5 of 5).
Note If the Transfer Roller Oscillator is locked, the address decoder is not at fault. Address decoder U302 decodes a single address for both the Offset Oscillator Pretune DAC and the Transfer Oscillator Pretune DAC. 9. If the pretune voltage is within the range listed in step 7, the Offset Oscillator is probably at fault. 10. Measure the Offset Oscillator’s frequency at A14TP302. If the frequency is not 200 MHz f10 MHz, connect a frequency counter to UlOl pin 3 (using a x10 oscilloscope probe).
21. Set the HP 8560A to the following settings: C E N T E R F R E Q . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...300 MHz SPAN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . OHz 22. Check that the voltage at U112 pin 5 is the same as that on U112 pin 3. 23. Set the HP 8560A to a SPAN of 100 kHz.
8. If the pretune voltage is not within the range in step 5, check U119A, U122A, Q102, Q103 and the Transfer Oscillator Pretune DAC address decoder, U302. Refer to function block AK of Al4 Frequency Control Schematic (sheet 5 of 5). 9. If the Offset Roller is locked, then the address decoder is correct; U302 decodes a single address for both the Offset Oscillator Pretune DAC and the Transfer Oscillator Pretune DAC. 10.
Main Oscillator PLL The Main Oscillator PLL provides an output signal in the range of 63 MHz to 106 MHz. This signal is the reference to the YTO PLL. The Sampler IF signal from the Al5 RF assembly is compared to this signal in the YTO Loop providing an error voltage to phase-lock the YTO. The Main Oscillator PLL’s sample-and-hold function is performed digitally using two DACs, U113A Coarse Adjust and U113B Fine Adjust.
13. If the Transfer Oscillator drive signal is not present, check the XFER AMP BIAS at J303 pin 3. The voltage should measure +2 Vdc to +4 Vdc. 14. Check that the voltage at U424B pin 7 is nominally -14 Vdc. Diodes CR302 and CR303 form a PIN diode switch that turns off the Transfer Oscillator drive to the mixer in Main Roller Spans (100 kHz
Unlocked Offset Lock Loop (Sampling Oscillator) Operation The Offset Lock Loop drives the A15A2 Sampler. The Offset Lock Loop’s sampling oscillator tunes to one of fifteen discrete frequencies between 280 MHz and 298 MHz. Refer to Al5 Schematic (sheet 3 of 3). M ixer A15U400 mixes the oscillator’s output with 300 MHz from the Reference PLL, producing a 2 MHz to 20 MHz IF signal. The 2 MHz to 20 MHz signal is divided down to 2 MHz or 2.
Table 10-15. Sampling Oscillator PLL Divide Ratios !klplitlg Center Divide TP 406, Oscillator Freq. (MHz) Freq.* R a t i o s T P 4071 (MHz) I 280.0 282.5 284.0 285.0 286.0 287.5 288.0 290.0 292.0 292.5 294.0 295.0 296.0 297.5 298.0 502.0 509.5 539.5 569.5 577.0 599.5 614.5 629.5 652.0 659.5 M Control Lines (MHz) 1 Bl 1 B2 I B3 I B4 I B5 INI M 1 389.5 427.0 449.5 464.5 479.5 N Control Lines 8 7 8 6 7 4 4 5 4 5 4 2.5 2.5 2.0 2.5 2.0 3 5 5 5 4 2.5 2.0 2.0 2.0 2.5 3 2 2 1 1 5 4 5 4 5 2.0 2.5 2.
14. Measure the loop-IF signal at the input to the IF Amp./Limiter (function block AK): U401 pin 2 20 MHz (approximately -6 dBm) 15. Confirm the presence of a 20 MHz square-wave signal at TP405. The square wave should go from +0.6 V to +2.2 V. 16. Set HP 8560A to the following settings: CENTER FREQ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 369.3 MHz SPAN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Unlocked Reference PLL Operation The Reference PLL’s 600 MHz output is generated by a 600 MHz SAWR (Surface Acoustical Wave Resonator) VCO. The SAWR provides a high Q feedback path in the oscillator ensuring good phase noise. If the oscillator is off-frequency, the phase-lock circuitry is probably at fault. If there is no signal present at A15J701, or if the level is less than -3 dBm, the oscillator has failed. Transistor Q703 provides active bias for oscillator transistor Q701.
15. Measure the signals at the following test points with an active probe/spectrum analyzer combination such as an HP 85024A/HP 8566A/B. The signal level at TP701 should be sufficient to drive an ECL input. TP506 U502 pin 15 50 MHz, >+3 dBm TP503 300 MHz, approximately +8 dBm 300 MHz (ECL level), approximately +3 dBm 600 MHz TP502 TP701 300 MHz,>+3 dBm 16.
29. If the front-panel CAL OUTPUT amplitude is out of specification and cannot be brought within specification by adjusting A15R561, CAL AMPTD, check the Calibrator AGC Amplifier with the following steps. Refer to function block W of Al5 RF Schematic (sheet 3 of 4). Note The 300 MHz CAL OUTPUT signal comes from the divided down 600 MHz which is passed through a leveling loop. The 300 MHz signal passes through a low-pass filter for reducing higher harmonics. These harmonics can fool the detector.
3. If the signal at A15TP602 is low, but the signal at A15TP504 is correct, press [s), INTERNAL MIXER,and SIG ID OFF. 4. Check that PIN diode switches CR603 and CR605 are reverse biased by approximately +10 Vdc. Refer to function block F of Al5 RF Schematic (sheet 1 of 3). 5. Measure 300 MHz signal at A15TP503 using an active probe/spectrum analyzer combination. If the signal is not approximately +lO dBm, refer to “Unlocked Reference PLL” in this chapter. 6.
7. If a correct signal is seen at A15TP201 but the signal at A15TPlOl is wrong, proceed as follows: . Use an oscilloscope to measure the signals at the following test points: A15J400 pin 1 A15J400 pin 3 t1.8 Vdc to t2.4 Vdc (LO.5 Vp-p variation) -1.8 Vdc to -2.4 Vdc (SO.5 Vp-p variation) If these levels are wrong, perform the “Power and Sampler Match Adjustments” in the Sampler Oscillator Adjustment procedure. Refer to Chapter 2.
Sweep Generator Circuit The Sweep Generator operates by feeding a constant current from DAC U307 into an integrator, U320B. See function block K of Al4 Frequency Control Schematic (sheet 2 of 5). This current is scaled by resistors R20 through R24 and U312B/C/D. See Figure 10-9. The capacitors used in the integrator depend on the sweep-time range; smaller-value capacitors provide faster sweep times. The integration is initiated by HSCAN going high.
C14.Cl5.Cl6 CURRENT SOURCE ’ I SWEEP U308, RZO-R24 U312B/C/D CR6 0 75oR R29 R65 526K IK U31 12A U312D SK1110 Figure 10-10.
ROLLER PLL’S l I I 1 w34 BLACK i ------I I I - - - e - h J304 ROLLER TEST A P P R O X -30 dBm 6 3 T O 1 0 5 . 5 MHz M A I N R O L L E R FREO t 6 0 0 MHz A P P R O X 0 dBm I w32 GRAY/VIOLEl 1 A15AZJl TO Al3 SECOND CONVERTER ---------m SAMPLER IF ;A15 R F A S S E M B L Y 10 MHz A P P R O X OdBm II t u / - 1 5 T O 0 dBm 63 TO 105.
A l 5 J501 S A M P L E R - - - - - - - - - - - - - - - - - - - - - - - - 1 5 - - T O - OdBm - - - - - - - - - - - - - I /P/O A l 4 F R E Q U E N C Y C O N T R O L 1 1 a I YTO LOOP I I YTO LOOP ERROR TO FM COIL w DRIVER 1 56 MHz/V I I I I I I I I I I I I I I I - I I TUNE DAC I VCO RAMP FROM I VCO SWEEP DRIVER I I I MAIN ROLLER SWEEP/HOLD I I J304 ROLLER TEST '-25 d&r I I I I I I 1 I I I MAIN PLL XFER OSC MAIN MIXER I TP301 dBn I I I
W 3 4 1ST L O S A M P J501 C A L O U T P U T TO FRONT PANEL TO SIG ID OSCILLATOR FRoM A7 LoDA i > -9 dBm 1 .
A21 OCXO (Option 003 only) Spectrum analyzers with Option 003, Precision Frequency Reference, use an oven-controlled crystal oscillator (OCXO) instead of the standard temperature compensated crystal oscillator (TCXO), 1oca t ed on the Al5 RF assembly. Jacks J305 and J306 on the Al5 RF assembly are located where the TCXO would normally be installed. The oven in the OCXO is powered only when the spectrum analyzer is powered on; there is no standby mode of operation.
11 RF Section The RF Section converts the input signal to a 10.7 MHz IF (Intermediate Frequency). See Figure 11-5 for a detailed section block diagram. Note The block diagrams for the Al4 and Al5 assemblies are located in Chapter 10, Synthesizer Section. Page 11-2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Troubleshooting Using the TAM 11-4 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Low Band Problems (50 Hz to 2.9 GHz) Low Band Problems . . .
Caution Use of an active probe, such as an HP 85024A, with another spectrum analyzer is recommended for troubleshooting the RF circuitry. If an HP 1120A Active Probe is being used with a spectrum analyzer, such as the HP 8566A/B, HP 8569A/B and the HP 8562A/B, having dc coupled inputs, either set the active probe for an ac coupled output or use a dc blocking capacitor (HP 11240B) between the active probe and the spectrum analyzer input.
Table 11-l. Automatic Fault Isolation References Manual Procedure to Perform Suspected Circuit Indicated by Automatic Fault Isolation Check 2nd IF Amplifier Third Converter Check 2nd IF Distribution Third Converter Check 10.
Table 11-2.
6. Check Al3 Second Converter mixer diode bias at A14J19 pin 1. The bias voltage should be between -150 and -900 mVdc. 7. Troubleshoot the signal path. Refer to the power levels listed on Figure 11-3, RF Section Troubleshooting. Low Band Problems 1. On the HP 8560A press (-1 and REALIGN LO & IF . If any error messages are displayed, refer to “Error Messages” in Chapter 6. 2. Perform External Mixer Amplitude Adjustment in Chapter 2.
A7 LODA (LO Distribution Amplifier) Note YTO unlock errors may occur if the power delivered to the A15A2 Sampler is less than -9.5 dBm. Frequency response will be degraded in both internal and external mixing modes if the output power is low or unlevelled. Caution Connecting or disconnecting the A7 LODA’s bias with the HP 8560A IuNE] switch on will destroy the A7 LODA. Always set the HP 8560A (LINE switch off before removing or reinstalling W12 to either the A7 LODA or A14JlO.
A9 Input Attenuator 1. Perform the Input Attenuator Accuracy test in Chapter 3 of the Installation and Verification Manual. 2. If there is a step-to-step error of approximately 10 dB or more, continue with step 3. 3. On the HP 8560A press [n), and ATTEN AUTO MAN until HAN is underlined. 4. Step the RF ATTEN from 0 dB to 70 dB. A “click” should be heard at each step. The absence of a click indicates faulty attenuator drive circuitry. 5.
Al3 Second Converter Caution The Al3 assembly is extremely sensitive to Electrostatic Discharge (ESD). For further information regarding electrostatic cautions, refer to “Electrostatic Discharge Information” in Chapter 1. 1. Connect the HP 8560A CAL OUTPUT to INPUT 50ohm. 2. Set the HP 8560A to the following settings: C E N T E R F R E Q . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...300 MHz SPAN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Al4 Frequency Control Assembly Note The block diagrams for the Al4 and Al5 assemblies are located in Chapter 10, Synthesizer Section. A7 LODA Drive See function block Z of Al4 Frequency Control Schematic Diagram (sheet 3 of 5) in the Component-Level Information binder. 1. Set the HP 8560A to the following settings: CENTER FREQ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .300 MHz SPAN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
F --m--m--m-------- 1 r;;7 1ST L O D I S T R I B U T I O N , All YTO J4 ’ J3 I 1JZ1SAMPLER 1ST MIXER OUT OUT -9 13 TO TO -2 16dhdBM 1ST L O O U T 1 4 . 5 T O 1 8 . 5 dBm I I t - - J SCHEMAT I C 3OF5 ,m”v”m”------- A S V I N C R E A S E S __I A7 OUTPUT INCREASES REF VOLTAGE L SK1115 Figure 11-2. A7 LODA Drive Al5 RF Assembly Note The block diagrams for the Al4 and Al5 assemblies are located in Chapter 10, Synthesizer Section. Confirming a Faulty Third Converter 1.
7. If a flat line is displayed within 2 dB of the reference level and the performance test passed, troubleshoot microcircuits A7, A8, A9, and A13. 8. If a flat line is displayed within 2 dB of the reference level and the performance test failed, troubleshoot the Al5 RF Assembly. Confirming Third Converter Output 1. Connect the HP 8560A’s CAL OUTPUT to INPUT 50 a. 2. Set the HP 8560A to the following settings: C E N T E R F R E Q . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3. Connect a signal source to A15J801 and set the source to the following settings: Frequency . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 310.7MHz Amplitude . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -30 dBm 4. Use an active probe with another spectrum analyzer to measure the signal at A15TP601. The signal should measure -18 dBm f2 dB confirming the operation of the 2nd IF Amplifier. 5.
Flatness Compensation Control See Function Block G of Al5 RF Schematic Diagram (Sheet 2 of 4) in the component- level information binder. The Flatness Compensation Control consists of a buffer amp (U9OlB) and two identical voltage-to-current converters (U901A and U9OlC). The thermistor RT901 in the buffer amp provides temperature compensation for the PIN diodes in the attenuator stages.
1. Set the HP 8560A to the following settings: TRIGGER . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..SINGLE SIG ID . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ON 2. Use an active probe with another spectrum analyzer to measure the signal level at A15TP602. 3. On the HP 8560A press SINGLE.
3. Check for a 3 Vp-p waveform at A15J302 using an oscilloscope (see Figure 11-3). 4. Check that the signal at A15J301 is 10 MHz 640 Hz (with TCXO reference) using a frequency counter. If necessary, perform the appropriate 10 MHz reference adjustment. 5. If there is no problem with INTernal 10 MHz reference operation, check EXTernal 10 MHz reference operation as follows: 6. Set the HP 8560A’s 10 MHz reference to external by pressing 10 MHz EXT . 7.
Graph 1: C [Ghan 1 1 1 0 0 V/div 1.00 v 5 0 . 0 ns/div 1 1 A15J302 Figure 11-4. 10 MHz TTL Reference at U303 Pin 5 II-16 RF Section 0 .
Table 11-4 lists the RF Section mnemonics shown in Figure 11-5 and provides a brief description of each. Table 11-4.
A10 Tracking Generator (Option 002) Block Diagram Description The A10 Tracking Generator consists of several smaller circuits. The A10 is not component-level repairable; a rebuilt exchange assembly is available. The block diagram of the tracking generator is unique in that it only recreates one of the spectrum analyzer’s intermediate frequencies. This minimizes isolation problems associated with a built-in tracking generator. Each of the blocks comprising the A10 Tracking Generator is described below.
Output Amplifier The output amplifier low-pass filters the signal emerging from the Output Mixer and then amplifies it into a usable range. The amplifier also contains a detector for leveling the output. Bias Board The bias board contains the ALC circuitry for the tracking generator and distributes dc power from the Al4 Frequency Control Assembly to the rest of the tracking generator.
3. Check maximum power available from the TG. Connect the RF OUT 50R to the INPUT 50R. Press (??%??I, IAMPLITUDE), 0, @, (z), LOG dB/DIV ,a, (dB), (mj, TRACKING GENRATOR , SRC PWR ON , MORE 1 OF 3 , ALC EXT. No connection should be made to the ALC EXT INPUT connector on the rear panel. The available power should always be greater than +l dBm. If the output is unleveled only at specific frequencies, a power hole will usually be visible at those frequencies. 4.
Flatness Out-of-Tolerance The output level flatness of the tracking generator is specified at a 0 dBm output power setting. In general, most flatness problems will be a result of a failure in the A10 Tracking Generator microcircuit. However the POWER LVL signal from the Al4 Frequency Control Assembly and the 1ST LO IN signal from the A7 LODA can also contribute to flatness problems. 1. Check the function of the POWER LVL signal from the Al4 Frequency Control Assembly.
3. Check for excessive LO feedthrough. Use the LO Feedthrough performance test in the Installation and Verification Manual, but check over a Center Frequency range of 300 kHz to 100 MHz. The LO Feedthrough will be 3.9107 GHz greater than the Center Frequency setting. Harmonic/Spurious Outputs Too High Harmonic and spurious outputs may be generated by A10 itself or may be present on the either the 600 MHz drive or 1st LO drive signal.
Power Sweep Not Functioning Properly Power sweep is accomplished by stepping Real Time Dac #l (R/T DACl) which adds an offset to the POWER LVL signal. Refer to Function Block S of Al4 Frequency Control Assembly schematic. R/T DACl is an 8-bit dac and can provide power sweeps of up to 12.8 dB. This is equivalent to 0.05 dB per dac step. Since R/T DACl has only 256 discrete settings but 601 points per sweep are digitized, up to three adjacent points per sweep may correspond to the same power level setting. 1.
7. If all of the checks above are correct, the tracking oscillator might not be functioning. Setup the HP 8560A as indicated in the Tracking Oscillator Range Adjustment procedure, using a spectrum analyzer, such as an HP 8566A/B, in place of the frequency counter. Try to adjust AlOC3 until a signal is displayed on the HP 8566A/B. If adjusting AlOC3 does not start the tracking oscillator functioning, the A10 Tracking Generator is suspect.
12 Display/Power Supply Section The Display/Power Supply Section contains the A6 Power Supply, A6Al HV Module, Al7 CRT Driver, and Al8 CRT. Figure 12-1 illustrates the section block diagram. Table 12-1 lists signal versus pin numbers for Power Cable Wl. Page Troubleshooting Using the TAM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12-4 Blank Display . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..
FRONT PANEL LED +5v ~ 7 FL4 A6 I‘OWER SUPPLi’ 4SSEMBLY LINE ^,.,, _r >WI ILH 110/220 VOLTAGE SELECTOR ON REAR PANEL) - 1 2 F A N 6 +28 Wl -15 +15 +5 JWARNING( +19v WHEN CRT SUPPLY TROUBLESHOOTING THE POWER SUPPLY - 1 5 v __) +15v __) it 1ov 4 USE AN ISOLATION H V SHUTDOWNt(+5V = H V O N ) TRANSFORMER AND CONNECT AGTPlOi T O A6TP301 HIGH VOLTAGE MODULE i AbAlW3 ‘I I POWER SUPPLY I N D ICATOR LEDS 42 IONTROLLER . . . . . . . . . . . . . . .
Table 12-1. Wl Power-Cable Connections (1 of 2) Signal NC NC A GND NC NC A GND NC NC A GND SCAN RAMF NC A GND -12.6 V -15V A GND -15 V f15 V A GND +15 V f28 V +28 V PWR UP -15 V -15 V +15 V +15 V +5 V +5 V +5 V +5 V D GND D GND A GND GND D GND D GND D GND D GND A2J1 A3J1 A4J1 A5J1 A6Jl A14J1 A15J1 (pins (pins (pins (pins (pins (pins (pins 3 3 48 3* 3 3 6 6 45 6* 6 6 9 10 9 42 9* 9 10* 9 12 13 14 15 16 17 18 19 20 21 12 39 12 12 14 15 16 .
Table 12-1. Wl Power-Cable Connections (2 of 2) Signal A2Jl A3Jl A4Jl A5Jl 46Jl- 414J1 415Jl :pins) :pins) :pins) :pins) :pins) (Pins) (Pins) 39 39* $5 V +5 V 12 11 10 9 +5 V 8 +5 V 7 44 44* +28 V 6 45 45* 46 46* 47 47* 48 48* 49 49* 50 50* $5 v $5 V LINE TRIGGER +15 V +15 V -15 V -15 V 40 40* 41 41* 42 42* 43 43* * Indicates signal source connectors.
Al7 CRT DRIVER I D &E”lSlON CONNECTOR) SK1121 Figure 12-2. Al7 Test Connector Table 12-3. TAM Tests versus Test Connectors Manual Probe Troubleshooting Test Measured Signal Lines Revision X-Deflection Amplifier Constant Current Source Focus Amplifier Bias Intensity Amplifier Bias Intensity Input Intensity Offset MS5 MS2, MS3 MS1 MS4 MS6 MS7 MS7 Blanking Control MS8 Blank Display Use the following procedure if the instrument’s display is blank.
9. Move the probe cable to A2J201, press SOFT KEY #l and wait five seconds. 16. Press SOFT KEY #4 . The results will be sent to the printer. 11. If a failure is indicated in any of these tests, the fault lies on the A2 Controller assembly. to obtain more information: a. Press the down arrow key one less time than the test number. (For example, press it twice for the third test on the list.) b. Press SOFT KEY 83 , then SOFT KEY #4, and when the printout is complete, SOFT KEY #6. 12.
r--------_-------_ I I I FRONT VIEW I , +15v I I SK1122 Figure 12-3. Probe Power Socket 5. If all of the power supply indicators along the outside edge of,the A2 Controller assembly are lit, the A6 Power Supply is probably working properly. 6. Press FREQUENCY, 0, (GHz). 7. Allow the analyzer to warm-up for at least one minute. 8. While observing the display, set the m switch off.
3. Perform the Display Adjustment in Chapter 2. Isolate the problem to either the X or Y axis by noting the behavior of the adjustments. If the line generator or fast zero-span portion of the adjustment fails, troubleshoot the A2 assembly. 4. If the adjustments do not remedy the problem, set the HP 8560A’s (LINE) switch off and place the Al7 CRT Driver in the service position. 5. Distortion confined to one axis (vertical or horizontal only), indicates a faulty Al7 assembly’s X or Y Deflection Amplifier.
6. Turn off the analyzer and place Al7 in the service position. Connect the ground lead of a high-voltage probe (HP 34111A) to the chassis, and use it with a DVM to measure A17J7( 10). 7. The nominal A17J7(10) voltage is -1600 Vdc, but the CRT will function with this voltage within 200 V of -1600 Vdc. 8. Adjusting A17R34 COURSE FOCUS should vary the A17J7(10) voltage by 150 V. If these voltages are correct, suspect the CRT. 9.
6. If blanking pulses are present, check A17TPlO with the oscilloscope. The TPlO signal should vary with the front-panel INTEN adjustment, and be approximately 55 Vp-p maximum. The signal will be composed of both blanking pulses and varying intensity levels for the lines being drawn. a. If a proper signal is not present at A17TP10, check A17Q1, Q2, CRl, and CR2. b. If the blanking pulses do not reach 40 Vp-p with maximum intensity, turn off the HP 8560A and check A17CRlO with an ohmmeter. c.
A6 Power Supply Assembly The HP 8560A uses a switching power supply operating at 40 kHz to supply the low voltages for most of the analyzer hardware and a 30 kHz switching supply (CRT Supply) to provide the high voltages for the CRT display. The CRT Supply will be treated as a separate supply since the remainder of A6 must be operating for the CRT Supply to operate. Kick starting occurs when there is a fault either on the power supply or on one of the other assemblies.
11. If there are pulses at TP206, or there are pulses at TP210, but not at TP206, the Buck Regulator Control circuitry is probably faulty. 12. Disconnect the power cord from the HP 8560A. 13. Connect the positive output of a current-limited dc power supply to the cathode of A6CR201 and the ground to A6TP201. 14. Set the current limit to about 500 mA and the voltage to 12 Vdc. 15. Connect a jumper from the power supply’s +12 V output to the end of A6R202 physically nearest A6U211. 16.
Line Fuse Blowing 1. If the line fuse blows with the (LINE) switch off, suspect either the Input Filter or the power switch cable assembly. 2. If the line fuse blows when the HP 8560A is turned on, disconnect the power cord and lift the drain of A6QlO2 from TP108. If the line fuse still blows, suspect U102. 3. If the fuse is working properly, check A6TP108 for a voltage of between +215 V and +350 v. 4. If the voltage at TP108 is correct, disconnect the power cord; remove and check A6QlO2. 5.
9. If the voltages do not return to near their nominal range, the A6 Power Supply is probably at fault. 10. If the +5 V supply is low, suspect the feedback circuit. Measure the voltage of the +5 V reference (U305 pin 5) and the f7.5 V references (U306B pin 7 and U306D pin 14). 11. Check output of U306A pin 1. If the feedback circuit is working properly, the output of U306A should be near +13 Vdc. 12. Check output of U302; its output should be high if the feedback circuit is working properly.
CRT Supply Dropping Out See function block K of A6 Power Supply Schematic Diagram in the Component-Level Information binder. The CRT Supply is a separate switching supply which provides the +llO Vdc for the Al7 CRT Driver from a winding on the A6Al HV Module. The CRT Supply operates at approximately 30 kHz. The exact frequency is determined by the inductance of the primary winding of A6AlTl and A6C407. The supply will only operate if the HV-SHUT-DOWN line is high.
Buck Regulator Control See function block H of A6 Power Supply Schematic Diagram in the Component-Level Information binder. The Buck Regulator Control pulse-width modulates the Buck Regulator and provides a synchronized signal to the DC-DC Converter Control circuitry. The Buck Regulator Control has two feedback paths. The first is the output of the Buck Regulator, which provides coarse regulation. The second is the Feedback Circuit which samples and compares the +5 Vdc output of the Output Rectifier.
Power Up See function block M of A6 Power Supply Schematic Diagram in the Component-Level Information binder. The Power Up circuitry generates the PWR UP signal, which tells the microprocessor that the supplies are up and stable. PWR UP will go high when the +5 Vdc supply exceeds +4.99 Vdc. PWR UP will go low when this voltage drops below t4.895 Vdc. Once PWR UP is set low, it will stay low for at least 50 ms before going high, even if the +5 Vdc supply exceeds i-4.99 Vdc before 50 ms have elapsed. .
12-18 Display/Power Supply Section
Component-Level Information Packets Component-Level information is available for selected instrument assemblies. The information for each repairable assembly is provided in the form of Component-Level Information Packets (CLIPS). Each CLIP contains a parts list, component-location diagram, and schematic diagram. Each CLIP has an HP part number which is changed whenever the HP part number for its related instrument assembly is changed.
Table A-l.
Table A-l. HP 8580A Spectrum Analyzer Documented Assemblies (continued) Board Assembly Instrument Serial Prefix Assembly Part Number CLIP Part Number’ Al4 Frequency Control (Opt.
Table A-2.
Table A-3.
A-6 Component-Level Information Packets
