INSTRUCTION BOOK Operator Manual AT-400 Antenna Tester © Copyright 2007 by Bird Electronic Corporation Instruction Book Part Number 920-AT400 Rev G
Safety Precautions The following are general safety precautions that are not necessarily related to any specific part or procedure, and do not necessarily appear elsewhere in this publication. These precautions must be thoroughly understood and applied to all phases of operation and maintenance. Resuscitation Personnel working with or near high voltages should be familiar with modern methods of resuscitation.
Bird AT-400 Antenna Tester Shock Hazard Do not attempt to remove the RF transmission line while RF power is present. Radiated RF power is a potential health hazard. Safety Symbols WARNING Warning notes call attention to a procedure which, if not correctly performed, could result in personal injury. CAUTION Caution notes call attention to a procedure which, if not correctly performed, could result in damage to the equipment.
Warning Statements The following equipment warnings appear in the text whenever there is a danger to people. WARNING Live RF energy. Do not touch or ground the center conductor of a live RF connection. Failure to comply may result in equipment damage and serious burns or death to personnel. Caution Statements The following equipment cautions appear in the text whenever the equipment is in danger of damage and are repeated here for emphasis. CAUTION Required input is 11 to 16 VDC @ 250mA.
Bird AT-400 Antenna Tester CAUTION 250mW max. input Exceeding the maximum input will cause damage to internal components. Do not connect transmitter output to the AT-400. Damage can also be caused by testing antennas near other transmitting antennas. If testing base station antennas, first measure the power at the coax end to be sure it does not exceed 250mW. CAUTION Harsh or abrasive detergents and some solvents can damage the display unit and information on labels.
ANULAR LA PROTECCIÓN DE SEGURIDAD DEL INSTRUMENTO. BENUTZUNG WIRD DAS GERÄT AUF ANDERE WEISE VERWENDET ALS VOM HERSTELLER BESCHRIEBEN, KANN DIE GERÄTESICHERHEIT BEEINTRÄCHTIGT WERDEN. UTILISATION TOUTE UTILISATION DE CET INSTRUMENT QUI N’EST PAS EXPLICITEMENT PRÉVUE PAR LE FABRICANT PEUT ENDOMMAGER LE DISPOSITIF DE PROTECTION DE L’INSTRUMENT. IMPIEGO QUALORA QUESTO STRUMENTO VENISSE UTILIZZATO IN MODO DIVERSO DA COME SPECIFICATO DAL PRODUTTORE LA PROZIONE DI SICUREZZA POTREBBE VENIRNE COMPROMESSA.
Bird AT-400 Antenna Tester WARTUNG ANWEISUNGEN FÜR DIE WARTUNG DES GERÄTES GELTEN NUR FÜR GESCHULTES FACHPERSONAL. ZUR VERMEIDUNG GEFÄHRLICHE, ELEKTRISCHE SCHOCKS, SIND WARTUNGSARBEITEN AUSSCHLIEßLICH VON QUALIFIZIERTEM SERVICEPERSONAL DURCHZUFÜHREN. ENTRENTIEN L’EMPLOI DES INSTRUCTIONS D’ENTRETIEN DOIT ÊTRE RÉSERVÉ AU PERSONNEL FORMÉ AUX OPÉRATIONS D’ENTRETIEN. POUR PRÉVENIR UN CHOC ÉLECTRIQUE DANGEREUX, NE PAS EFFECTUER D’ENTRETIEN SI L’ON N’A PAS ÉTÉ QUALIFIÉ POUR CE FAIRE.
About This Manual About this Manual Many people read the operators manual only as a last resort. If you are one of those people, you should at least read the next two pages so that you can find the information when you do need it. You will also learn where to find valuable time saving information. Changes to this Manual We have made every effort to ensure this manual is accurate at the time of publication.
Bird AT-400 Antenna Tester Chapter Layout Introduction—Will help you become familiar with the parts of the Antenna Tester, Features Available, and Optional Equipment. Basic Operation—Everyone should read this section! This section will provide the information required to get the Antenna Tester powered up, and provides helpful information about how to operate the Antenna Tester, and some time saving hints for alternate operating methods.
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Table of Contents Safety Precautions . . . . . . . . . . . . . . . . . . . . . . . . . . . . i About This Manual . . . . . . . . . . . . . . . . . . . . . . . . . . . vii Introduction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 Items Supplied . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 Component Description . . . . . . . . . . . . . . . . . . . . . . . . . . 2 Display Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 Features . . . . .
Chapter 1 Introduction Items Supplied 1 4 2 3 Figure 1 Supplied Items 1. 2. 3. 4. 5.
Bird AT-400 Antenna Tester Component Description 14 13 1 2 12 11 10 3 9 8 4 7 6 5 Figure 2 Component Description 1. 2. 2 LCD Display External DC Connector Backlit liquid crystal display. Connect either the ac adapter or the cigarette lighter adapter. External supplies operate the unit and charge the internal battery.
Introduction 3. Cursor Keys Left Arrow Right Arrow Up Arrow Down Arrow 4. Backlight Key 5. On Key 6. +/- Key 7. 8. Enter Key ESC Key 9. Menu Key 10. Select Key 11. Numeric Keys 12. Menu Select Keys 13. Test Port 14. Serial Port Press in swept frequency mode to move the cursor to the left. Press during data entry to erase data. Press in swept frequency mode to move the cursor to the right. Moves the cursor to the maximum point on the displayed trace.
Bird AT-400 Antenna Tester Display Description 10 9 8 1.35 260.00 MHz 2.0 1 * 2 3 VSWR Busy 7 6 1.0 65.00 4 Band MHz Meas Units 10 5 520.00 Sweep Type Trace 9 Limit 8 1.35 260.00 Mhz 1.2 1.
Introduction 1. Sweep Rate Indicator Blinks when sweeping. 2. Measurement Units Indicates selected measurement units. 3. Trace Graphic display of measured results across selected frequency band. 4. Menu Select Key Labels Defines function of menu select keys located below the display. 5. Frequency Band Scale Displays frequency band selected. 6. Cursor Used to select measurement position on the trace. 7.
Bird AT-400 Antenna Tester Features Swept Frequency Mode — Fast scan shows VSWR, ρ, match efficiency or return loss across an entire band. A movable cursor can be used to pinpoint a scan frequency and the corresponding measurement value is displayed. Single Frequency Mode — Provides measurement information in units of Reflection Coefficient (ρ); Voltage Standing Wave Ratio (VSWR); % Match, or Return Loss (dB) at one frequency on a simulated meter movement.
Introduction Optional Equipment Automobile Cigarette Lighter Adapter — (P/N 5A2238-1) Connects tester to standard 12V automotive cigarette lighter jack. Carrying Case — (P/N 5000-030) Convenient and protective, large enough to carry the tester, AC adapter, connectors, field strength antenna and instruction book. Verification Kit — (P/N 7000A445) Used to verify tester performance. Includes standard mismatch and connector adapter.
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Chapter 2 Basic Operations Getting Started This section describes initial quick steps to get started. For detailed information regarding connecting the Antenna Tester refer to that section at the end of this chapter. Note: This unit is shipped with the batteries not charged. Charge batteries overnight or for at least 8 hours before use. ON Power On/Off y To turn the Antenna Tester on, momentarily press the ON key. The results of a self test will be displayed if a failure is present.
Bird AT-400 Antenna Tester Blinking Cursor (black square) The cursor will be blinking in the selected area, indicating that the parameter for that area can be changed. ENTER Enter Key All data entry, and mode changes accessed using select key, require the enter key to be pressed before they are initiated. Up/Down Arrow Keys When a function is enabled for change, the UP or DOWN arrow keys can be used to either scroll through your choices or increase/decrease the numerical value.
Basic Operations Messages There are five utility messages that can be displayed to inform you of equipment, or procedural, conditions. “Lo Batt” is displayed when battery voltage is less than 6.6V, refer to maintenance section for charging batteries. “Busy” is displayed during mode changes indicating the measurement information is being updated. “Hold” is displayed when in the Swept Frequency mode, and Single Hold is the selected sweep type.
Bird AT-400 Antenna Tester Return to Factory Presets When the Antenna Tester is turned on, the various software parameters will be set to the condition they were at when the tester was turned off. To return the parameters to the factory setting follow the steps below. y The parameters will be set to the conditions listed below. Software Parameter Mode Start Stop Measurement Units Scale Sweep Type Limit Value Limit Audio Baud Rate Auto Shut-off Timer Audio Cursor y y y 12 Press the MENU key.
Basic Operations Set Serial Baud Rate Measurement data can be transferred between the AT-400 and a personal computer using the serial port and optional interface software. The data can then be used for analysis, printed, or stored. The data transfer rate (baud rate) between the Antenna Tester and computer must be identical and set to 9600. To change the baud rate for the serial port on the Antenna Tester, follow the steps below. Complete interface software instructions are included with the software.
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Chapter 3 Installation The following paragraphs will explain how to connect the Bird Antenna Tester for various operations. Refer to the component description diagram on page 2 if needed. Power Supply The AT-400 can use an external power source. Using the ac adapter or the 12V cigarette lighter adapter will also charge the battery. Using the ac adapter, charge time is about 8 hours. Using the cigarette lighter adapter, charge time will depend on the car battery charge.
Bird AT-400 Antenna Tester Connecting the Antenna WARNING Live RF energy. Do not touch or ground the center conductor of a live RF connection. Failure to comply may result in equipment damage and serious burns or death to personnel. CAUTION AVOID STATIC DISCHARGE Use proper Electrostatic Discharge (ESD) precautions to avoid static discharge when making connections to the test port. Equipment failure can occur if the test port is subjected to ESD. CAUTION 250mW max.
Chapter 4 Measure Match Understanding the Operating Modes The Antenna Tester is connected and the operating frequency band is selected (see basic operation). User selections are customized, the power is on, and the top level menu is displayed (also in basic operation). Now what? Before we explain how to measure the antenna match, a brief discussion of your options is in order.
Bird AT-400 Antenna Tester Figure 5 Single Frequency 1.35 260.00 MHz 1.2 1.5 VSWR Freq MHz Units Manual Auto Scale Scale Audio Off Measurement Units Rho (Reflection Coefficient), VSWR (Voltage Standing Wave Ratio), Match Efficiency (%), and Return Loss (dB), are different units of measurement that can be used to present the same information. (Similarly, Celsius and Fahrenheit are different units of measurement used to express the same temperature).
Measure Match Antenna manufacturers often use VSWR for specifications. Match Efficiency is popular for testing because it is easy to determine a good match versus a bad match. For example a system with a VSWR of 1.50 would show -13.98 dB Return Loss and 96% Match Efficiency. Auto Scale vs. Manual Scale In swept mode Auto Scaling sets the measurement unit scale to make the trace easier to read.
Bird AT-400 Antenna Tester In the single frequency mode Auto Scaling sets the measurement unit scale so the pointer is mid range of the previous reading. The maximum and minimum scale values are approximately 10% higher or lower than the measured value. Figure 8 Auto Scaling Single Frequency Mode 1.35 260.00 MHz 1.2 1.5 VSWR Freq MHz Units Manual Auto Scale Scale Audio Off This setting is an operator preference based on the mode that best presents the desired information.
Measure Match Swept Frequency Select Frequency Band There are two options for selecting the frequency band. The first is simply to enter the start and stop frequencies. The second is to enter a span frequency, which is the desired width of the band, and a center frequency, that will be used as the center of the band. y y y y Press the MENU key. Press the SWEPT FREQ key. Press the BAND key.
Bird AT-400 Antenna Tester Select Measurement Units Antenna match information can be presented using four different measurement units. Depending on your application, follow the steps below to select Rho, VSWR, %Match or Return Loss. y y y y y y Press the MENU key. Press the SWEPT FREQ key. Press the MEAS UNITS key. Press the UNITS key. Press either the RHO, VSWR, %MATCH or RETURN LOSS key. The selected unit will be shown on the left side of the display.
Measure Match NOTE: If an out of range value is entered, the minimum (if under-range) or maximum (if over-range) value will be substituted. If a maximum value that is lower than the minimum value is entered, the cursor will blink again on the minimum value waiting for a correct entry. The actual range depends on the units selected. NOTE: Using the arrow keys will keep you in the acceptable range.
Bird AT-400 Antenna Tester comparison. For example, if you save a trace displayed in VSWR, you can compare it to a trace displayed in %Match. You can also change the frequency band of the new trace to effectively zoom in on a particular section of the saved trace. This may be helpful in pinpointing a problem area in a failed limit test. Figure 10 Save a Trace 1.35 260.00 MHz 2.0 VSWR 1.0 65.00 Reg-1 Empty MHz Reg-2 Empty Reg-3 Empty 520.
Measure Match y y y y y y y Press the MENU key. Press the SWEPT FREQ key. Press the TRACE key. Press the RECALL TRACE key. Press the REG-n key for the desired trace, press the MORE RECALL key to access 5-8 and again to access 9-12. If needed, use the ESC key to back up. The saved trace will be displayed and the corresponding register number will be shown at the bottom of the display.
Bird AT-400 Antenna Tester or fail will be displayed at the top of the display and an audible tone can be enabled to indicate a fail situation. Limit testing is probably the most labor-efficient mode for operating the AT-400. Since all the software settings are retained when the tester is turned off, once the limit test is set up its simply a matter of connecting the next antenna system, turning on the power and reading pass or fail. Turn Audio On/Off Audio tone for fail indication.
Measure Match Using a Trace as the Limit The trace you want to use for the limit must be saved. You can have the current antenna test running or start it after you set up the limit test. Figure 11 Dotted Outline of Limit Trace 1.35 260.00 MHz * 2.0 PASS VSWR 1.0 65.00 Swept Freq y y y y y MHz Single Field Freq Str 520.00 Util Test Press the MENU key. Press the SWEPT FREQ key. Press the LIMIT key. Press the TRACE - > LIMIT key. Press the REG-n key where the trace is stored.
Bird AT-400 Antenna Tester Clearing a Limit Follow the steps below to clear either an operator defined limit value or a trace limit. The trace will still be stored in memory, the limit value will be erased. y y y y Press the MENU key. Press the SWEPT FREQ key. Press the LIMIT key. Press the CLEAR LIMIT key. The value field will change to off if an operator value was being used, the dotted outline of the limit trace will be removed if a trace was being used.
Measure Match Select Measurement Units Antenna match information can be presented using three different measurement units. Depending on your application, follow the steps below to select Rho, VSWR, %Match or Return Loss. y y y y y Press the MENU key. Press the SINGLE FREQ key. Press the UNITS key. Press either the RHO, VSWR, %MATCH or RETURN LOSS key. The selected unit will be shown in the center of the display. Press the RETURN key to go back one menu level.
Bird AT-400 Antenna Tester NOTE: If an out of range value is entered, the minimum (if under-range) or maximum (if over-range) value will be substituted. If a maximum value that is lower than the minimum value is entered the cursor will blink again on the minimum value, waiting for a correct entry. The actual range depends on the units selected. NOTE: Using the arrow keys will keep you in the acceptable range.
Chapter 5 Field Strength Field Strength Measurement With the field strength antenna installed, the Antenna Tester can be used to optimize the radiated signal of any transmitter from 65 to 520MHz. This is a relative measurement. The measurement sensitivity is such that a full scale deflection will occur for a field of 0.22 Volts/Meter at 400 MHz. The gain factor can be adjusted to increase the measurement sensitivity to 0.02 Volts/Meter.
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Chapter 6 Maintenance Cleaning CAUTION Harsh or abrasive detergents and some solvents can damage the display unit and information on labels. Clean the antenna tester and the display with a soft cloth dampened with mild detergent and water only. Calibration For best performance and accuracy, the Antenna Tester should be calibrated once every 12 months. Return the unit to an authorized Bird Service Center.
Bird AT-400 Antenna Tester Operational Tests Power-up There are several operational tests run at power up. The test is displayed only if any of the tests fail. The results are displayed to the right of the test as shown in Figure 12. If you would like the test screen displayed regardless of results, press any key while pressing the ON key at initial power up. If any test fails, check the troubleshooting section for possible correction.
Maintenance Battery Test The battery test checks the output voltage of the batteries. The result is displayed in a simulated analog meter type graphic with the value shown at the top of the display. The scale is set from 6-8V. If the voltage measured is less than 7V you should charge the batteries. Figure 13 Battery Test 7.71 V 6.0 8.0 Battery Voltage Return NOTE: The AT-400 will shut off if the battery is too low however, full accuracy is maintained at any battery voltage.
Bird AT-400 Antenna Tester Figure 14 Display Test y y y y y Display Display Display Display Display Display Display Display Display Display Display Display Display Display Display Test Test Test Test Test Test Test Test Test Test Test Test Test Test Test 1234567890 1234567890 1234567890 1234567890 1234567890 1234567890 1234567890 1234567890 1234567890 1234567890 1234567890 1234567890 1234567890 1234567890 1234567890 ABCDEFGH ABCDEFGH ABCDEFGH ABCDEFGH ABCDEFGH ABCDEFGH ABCDEFGH ABCDEFGH ABCDEFGH ABCDEF
Maintenance y To test the keypad, Press each key (except ESC and ON). The value next to Keypad is hexadecimal and corresponds to the key pressed. If the value does not change for each key, refer to Troubleshooting in this section. y Press the ESC key to stop the test. Battery Replacement The NiCad batteries need to be replaced when fully charged batteries provide less than 2 hours operation. Carefully follow the instructions below to replace the batteries.
Bird AT-400 Antenna Tester 9. Replace the six screws. 10. Run the battery test on page 35 of this section. Fuse Replacement CAUTION Replace with only the same type and rating fuse. 315mA 250V y Follow the steps outlined in Battery Replacement replacing the fuse where replacing the batteries is indicated.
Maintenance Troubleshooting Operator maintenance or service is limited to battery and fuse replacement. Any other required service must be performed at at an authorized Bird Service Center. Refer to the following paragraphs for help in isolating error conditions. The Antenna Tester will not power up. Power for the Antenna Tester can be provided in three ways—the internal batteries, an AC mains adapter or an optional automobile cigarette lighter adapter. Try to power the tester using each available means.
Bird AT-400 Antenna Tester ROM, EEPROM, RAM, A/D, TEMPR, PLL Test Fails Ensure the results are valid by repeating the self test or turning the unit off then back on. If the problem persists return the unit for service. Stuck Keys Test Fails If any characters other than 0 are displayed next to stuck keys during power up test, perform the keypad test on page 36 of this section.
Maintenance to a perfect match. Measurement results are not accurate under these circumstances. The remedy is to disable the interfering source, if possible, or postpone the measurement to a time when the interfering source is not operating. Customer Service Any maintenance or service procedure beyond the scope of those in this chapter should be referred to a qualified service center. If you need to return the unit for any reason, contact the Bird Service Center for a return authorization.
Bird AT-400 Antenna Tester Parts List Part Name Part Number AT-400 Complete 7000A401 Parts Supplied with AT-400 Complete, or installed when shipped.
Maintenance Specifications Frequency Range Frequency Resolution Measurement Range VSWR Match Efficiency Return Loss Rho Measurement Speed Single Frequency Swept Frequency Test Port Impedance Connector Field Strength Range Sensitivity 65 to 520 MHz 20 kHz 1.00 to 100.00 0 to 100% -32 to 0 dB 0.000 to 1.000 (Typical) 5 Readings/second 1 Sweep/second 50Ω nominal (Field Interchangeable) Female N 0 to 100% Relative Full scale deflection at 0.22 Volts/Meter at 400 MHz, depending on gain setting.
44 Center MHz % Match Manual Scale Value Limit Span MHz Rho Return Preset Return Return Return Disp Test Return Return Return Self Test Audio (ON, OFF) Return Clear Limit Rho Audio (ON, OFF) Clear Trace Return Loss Auto Scale Return Timer Batt Test Test Audio (ON, OFF) Trace -> Lim Return Return Loss Auto Scale Cont Serial Recall Trace % Match Save Trace Trace Util Auto Gain Manual Scale Gain Field Str VSWR Units Single Hold Sweep Type VSWR Units Meas Units
Limited Warranty All products manufactured by Seller are warranted to be free from defects in material and workmanship for a period of one (1) year, unless otherwise specified, from date of shipment and to conform to applicable specifications, drawings, blueprints and/or samples.
