S T A R L I N E® S E R I E S MB*/* MiniBridger Amplifiers Installation and Operation Manual 2 ASSEMBLED IN MEXICO 4 5 6 1 3
CAUTION RISK OF ELECTRIC SHOCK CAUTION: TO REDUCE THE RISK OF ELECTRIC SHOCK, DO NOT REMOVE COVER (OR BACK). NO USER-SERVICEABLE PARTS INSIDE. REFER SERVICING TO QUALIFIED SERVICE PERSONNEL. Caution These servicing instructions are for use by qualified personnel only. To reduce the risk of electrical shock, do not perform any servicing other than that contained in the Installation and Troubleshooting Instructions unless you are qualified to do so. Refer all servicing to qualified service personnel.
FCC Compliance This equipment has been tested and found to comply with the limits for a Class A digital device, pursuant to Part 15 of the FCC Rules. These limits are designed to provide reasonable protection against harmful interference when the equipment is operated in a commercial environment. This equipment generates, uses, and can radiate radio frequency energy and, if not installed and used in accordance with the Installation Manual, may cause harmful interference to radio communications.
Contents Section 1 Introduction Using This Manual............................................................................................................................................................................1-2 Related Documentation ...................................................................................................................................................................1-3 Document Conventions ............................................................................
ii Contents Automatic Drive Unit............................................................................................................................................................. 3-15 ADU Pads and Levels ........................................................................................................................................................... 3-15 Return Path Alignment ................................................................................................................
Contents iii Figures Figure 1-1 MB*/* — closed ..............................................................................................................................................................1-2 Figure 2-1 MB*/* — open.................................................................................................................................................................2-1 Figure 2-2 MB*/* configurator....................................................................................
Section 1 Introduction ® ® The Motorola STARLINE series of MiniBridger amplifiers, model MB*/*, accept a single input and provide high operational gain to a single or dual output. The high gain makes the MB*/* series ideally suited for a hybrid fiber-coax system as well as conventional tree-and-branch designs. The MB*/* amplifier series complies with IEEE C62.41-1991 and Bell Core GR-1098 specifications for overvoltage testing as recommended by Cable Labs. The MB*/* platform is also FCC and CE approved.
1-2 Introduction Figure 1-1 illustrates a closed MB*/*: Figure 1-1 MB*/* — closed Using This Manual The following sections provide information and instructions to install and operate the MB*/*. Section 1 Introduction provides a product description, related documentation, the technical help line, and repair/return information. Section 2 Overview describes the MB*/* and includes details on the various options and their functions.
Introduction 1-3 This manual assumes that all channels are standard National Television Standards Committee (NTSC) analog channels. Refer to catalog specifications for further details pertaining to signal levels of digital channels above 550 MHz. This manual also uses 870 MHz as the reference frequency unless another frequency is given. For example, quoted cable loss is understood to be at 870 MHz.
1-4 Introduction Calling for Repairs If repair is necessary, call the Motorola Repair Facility at 1-800-642-0442 for a Return for Service Authorization (RSA) number before sending the unit. The RSA number must be prominently displayed on all equipment cartons. The Repair Facility is open from 7:00 AM to 4:00 PM Pacific Time, Monday through Friday. When calling from outside the United States, use the appropriate international access code and then call 52-631-311-1100, to contact the Repair Facility.
Section 2 Overview The MB*/* is a dual-output amplifier while the MB*/S* is a single-output amplifier used in CATV distribution systems. Both models accommodate installation of the optional return amplifier to enable two-way signal flow. All models are high-gain, three-stage hybrid amplifers designed to drive both a limited cascade and a local distribution system. The MB*/* is powered by the 60/90 Vac cable supply and can be configured to pass this power to additional amplifiers and line extenders.
2-2 Overview Configuration The MB*/* is fully configured in the factory per customer request. It is recommended that you verify the configuration listed on the outside of the shipping carton with the configuration that you ordered. The shipped configuration is also noted in a label on the side of the electronics chassis and the housing.
Overview 2-3 Housing The MB*/* is furnished in an MB-HSG aluminum housing that protects the electronics from weather and dissipates internally generated heat. Figure 2-3 illustrates a top view of the MB-HSG housing and provides its dimensions: Figure 2-3 MB-HSG dimensions — top view 15.4 9.6 Figure 2-4 illustrates a side view of the MB-HSG and provides its dimensions: Figure 2-4 MB-HSG dimensions — side view 5.
2-4 Overview Figure 2-5 provides top and side view dimensions of the optional MBP-HSG bypass housing: Figure 2-5 MBP-HSG dimensions 17.7 10.4 7.3 Coaxial cable connections to the housing are made using conventional 5/8 × 24 threads per-inch stinger-type connectors. Five port plugs in the cover enable access to internal test points without opening the housing.
Overview 2-5 The included clamp and bolt assemblies enable you to mount the standard and bypass housings. For instructions on aerial and pedestal installation refer to Section 5, “Installation”. Gaskets Each housing is equipped with a recessed woven-wire RF gasket and a silicone-rubber weather gasket to provide a seal between the housing base and lid. These gaskets provide efficient ground continuity, RF shielding, and weather protection.
2-6 Overview Port Locations Five port plugs in the cover enable access to internal test points. The input and output ports provide connection for coaxial cables and are protected by factory-inserted threaded plugs or plastic cap plugs. Discard the plastic cap plugs when you install the cable connectors.
Overview 2-7 Figure 2-8 illustrates a block diagram of the MPPS-II power pack: Figure 2-8 MPPS-II block diagram 60/90 Vac EMI Filter Bridge rectifier Isolation transformer Preregulator Precision regulator 24 Vdc Overvoltage and power-factor correction Figure 2-9 illustrates the MPPS-II installed in the upper half of the MB-HSG: Figure 2-9 MPPS-II power pack HI LO AC TEST POINT NO USER SERVICABLE PARTS INSIDE USE CAUTION WHEN MAKING INTERNAL ADJUSTMENTS WITH COVER REMOVED SEE INSTALLATION MANUAL
2-8 Overview Figure 2-10 illustrates the location of the LO/HI voltage selector and the gas discharge tube surge protector on the MPPS-II: Figure 2-10 60/90 volt selector Voltage selector Gas discharge tube or optional FTEC J1 HI LO TP1 R 54 TP2 460132-001 You must remove the MPPS-II cover to access the selector illustrated in Figure 2-10. Section 3, “ Amplifier Setup” explains changing the setting of this selector to meet system requirements.
Overview 2-9 Factory installed 20-amp fuses, illustrated in Figure 2-11, provide power passing to additional amplifiers: Figure 2-11 Power passing fuse locations F in MB 87 75 55 IN S J A K E M F2 G -20dB -20dB JXP IN STATUS MONITOR OUTPUT H JXP 2 FWD EQ L -20dB JXP 3/4 BODE FUSE PORT 2 L MDR H FUSE ALIGN DOTS REF ER TO MANUAL F OR FUS E VALUE S MAN JXP ADU H L I C S JXP 2 JXP POWER -20dB DRIVE UNIT JXP THERM -20dB ADU ADU MAN PORT 3 I C S TDU 3 4 -20dB CONTROL
2-10 Overview Following the Bode board, a JXP pad facility adjusts the RF level into the interstage hybrid amplifier and the MDR-*MB/*/II controls flatness and provides equalization. Because these losses are located interstage, the noise figure is only significantly impacted by the insertion loss of the forward cable equalizer or broadband cable simulator, and the input pad if its value is increased from zero.
Overview 2-11 Figure 2-13 illustrates the interconnection between these components in the single output MB*/S*: Figure 2-13 MB*/S*single output block diagram +25.0 dB E-GaAs +23.0 dB Silicon -4.0 dB ** JXP-B Fltn. Cntrl. PP -20 dB TP -1.7 dB F RF/ AC RF AC -1.0 dB R ** BODE Manual JXP-B -1.0 dB ** +19 dB PP MDR Auto JXP-B -1.0 dB ADU/ TDU H L -1.0 dB ** ** -20 dB TP -0.4 dB Surge protector -0.5 dB ** ** SRE -0.3 dB ** THERM JXP-B LPF +25.0 dB L +30.0 dB H 24 Vdc JXP-B -0.
2-12 Overview Return Path, RA-Kit/H or RA-Kit/L The circuit board of the MB*/* amplifier accommodates the optional return path. The return path kit, Model RA-Kit/H or RA-Kit/L, includes the return amplifier hybrid (illustrated in Figure 2-15) and jumpers. This equips the MB*/* to pass signals in the return or upstream direction. The standard circuit board contains all components including the diplex filters, with extended return bandwidth, for the amplifier input and output.
Overview 2-13 Figure 2-14 illustrates the LL-MB-F3 and the required cable connections to the amplifier module: Figure 2-14 LL-MB-F3 status monitor G- to F-type adapter MB 87 75 55 S J A K E M G -20dB -20dB JXP IN STATUS MONITOR OUTPUT H IN JXP 2 FWD EQ L -20dB JXP 3/4 BODE FUSE PORT 2 L MDR H FUSE ALIGN DOTS REFER TO MANUAL FOR FUSE VALUES JXP ADU MAN H L I C S JXP 2 JXP POWER -20dB DRIVE UNIT JXP THERM -20dB ADU ADU MAN PORT 3 I C S 3 4 JXP 3/4 TDU -20dB CONTROL
2-14 Overview Options and Accessories The factory ships the MB*/* as a fully functional unit, but you must configure it appropriately for the field location requirements. You must install the correct forward equalizer or broadband cable simulator and input pad to place the unit in service. Section 3, “ Amplifier Setup” provides information to assist you in this task. Use model JXP-*B pads to control field signal levels.
Overview 2-15 Model Description Function ICS Ingress Control Switch This option enables remote monitoring, isolation, and reduction of ingress on the return path by providing signal attenuation of 6 dB or cutoff of 38 dB typical. The unit is shipped with a jumper in this location. SP or DC/* Output passives These options should be installed in place of the JMP jumper to activate the third output of the MB*/*.
Section 3 Amplifier Setup This section provides instructions for fully configuring the MB*/* and describes the proper forward and return path alignment procedures.
3-2 Amplifier Setup Secure the electronics chassis in the housing and torque to 18 to 22 in-lbs. to facilitate heat transfer and avoid damage from overheating. Perform a bench alignment. Pre-aligning the MB*/* response on the bench (Section 4, “ Bench Testing” ) for a system signature simplifies field alignment. Field sweep the entire bandwidth of the amplifier to correct frequency response for passive signature and roll-off.
Amplifier Setup 3-3 Substituting this information into the above equation provides the following result: 11 dB + 26.1 dB − 12 dBmV − 12 dB = 13.1 dB The slope of the required equalizer is 13.1 dB. Table 3-1 and the graph in Figure 3-1 show that 13.1 dB of slope is caused by approximately 18 dB of cable at 870 MHz. Therefore, the correct equalizer is model SFE-87-18.
3-4 Amplifier Setup Figure 3-1 illustrates a graph of the equalizer slope versus equalizer value information presented in Table 3-1. The amount of cable equals the equalizer value.
Amplifier Setup 3-5 Cable Simulators STARLINE cable simulators, model SCS-*, are used in place of fixed equalizers in systems where: (1) the amplifiers are located close together, (2) there are large amounts of flat loss from passive components, or (3) it is necessary to compensate for reverse cable tilt. The simulators fit in the same location as the equalizers. Table 3-2 and Figure 3-2 help you choose the correct simulators.
3-6 Amplifier Setup The information in Table 3-2 is shown as a graph in Figure 3-2: Figure 3-2 Frequency versus cable slope 0 Cable slope (dB) -1 -2 SCS-1 -3 SCS-2 -4 SCS-3 -5 SCS-4 -6 SCS-5 -7 870 800 750 700 650 600 550 500 SCS-10 450 -12 400 SCS-9 350 -11 300 SCS-8 250 -10 200 SCS-7 150 -9 100 SCS-6 40 -8 Frequency (MHz) Input, Midstage, and Output Pads Install model JXP-*B pads to attenuate the signal per system design drawings.
Amplifier Setup 3-7 Output Passives Use the furnished JMP jumper to select port 3 or port 4 as the second output port. Install the proper output splitter to obtain signal output at port 3 and port 4. The SP splitter provides equal output at ports 3 and 4. If you require high-level output at port 3 or 4 and an 8 dB, 10 dB, or 12 dB lower level at the other port, install the appropriate DC/8, DC/10, or DC/12 directional coupler.
3-8 Amplifier Setup Flatness Control All amplifiers are pre-aligned for optimal station flatness for the slope value ordered therefore, there is usually no need to adjust the MDR board. However, you can make minor adjustments, if necessary to achieve flatness across the passband. The MDR-*MB/*/II board includes flatness controls and a fixed cable equalizer for 750 MHz or 870 MHz.
Amplifier Setup 3-9 Figure 3-6 MDR-*MB/*/II board C3 C2 C7 R2 R3 R4 C6 C4 C1 R5 To obtain maximum flatness: 1 Adjust C6 and R5 for the flattest response in the mid- to lower-portion of the passband. 2 Adjust C1 for the flattest response in the low- to mid-range of the passband. 3 Adjust C3 and R4 for a peak at approximately 100 MHz to 300 MHz using the following steps: a. Set R4 to minimum resistance to show where the peak occurs for this RC network adjustment (R4/C3). b.
3-10 Amplifier Setup Figures 3-7 and 3-8 illustrate the approximate effects on the frequency response of the MB*/*: Figure 3-7 Effects of flatness controls on the MDR-8MB/*/II board CH 1 S 21 /M log MAG 2 dB/ REF 41.34 dB C2 and R3 C3 and R4 C7 and R2 START 5.000 000 MHz C6 R5 C1 C4 STOP 870.000 000 MHz The changes in response were obtained by comparison against a normalized trace to emphasize the effect of the various controls.
Amplifier Setup 3-11 Figure 3-8 Effect of flatness controls on the main board: CH1 S21 /M log MAG 2dB/ REF 41.35dB Cor C116 2 1 STOP 870.000 000 MHz CH 1 START 54.000 000 MHz CH1 S21 /M log MAG 2dB/ REF 41.35dB Cor C118 2 1 CH 1 START 54.000 000 MHz STOP 870.
3-12 Amplifier Setup Directional Coupler Test Points Accurate −20 dB directional-coupler test points are available at the input and at the output of the MB*/*. Because these test points are 75-ohm source impedance, they do not require special test probes. After the output hybrid, a second directional coupler provides signal to the optional ADU board. This signal is used only when the ADU board is installed. It is not necessary to terminate this port when the ADU is not installed.
Amplifier Setup 3-13 Table 3-3 Gain reserve versus ambient temperature Temperature 8 Gain Reserve Above 110°°F (43°°C) 4 dB 32°°F (0°°C) to 110°°F (43°°C) 5 dB Below 32°°F (0°°C) 6 dB Check the amplifier output tilt by measuring the high band- and low band-edge carriers. High = channel 116 (745.25 MHz) or channel 136 (865.25 MHz) Low = channel 2 (55.25 MHz) or channel 3 (61.
3-14 Amplifier Setup Thermal Drive Unit The TDU senses temperature and controls the Bode board. It is assumed that the cable is subjected to the same or similar temperature; therefore, the TDU should not be used for underground installations. To set-up the TDU: 1 Place the jumper on the TDU (Figure 3-9) to the LOW, MEDIUM, or HIGH position. This setting specifies the amount of cable for which the TDU compensates at the highest frequency preceding the MB*/* station.
Amplifier Setup 3-15 Automatic Drive Unit The ADU operates by using surface acoustic wave (SAW) filters to select a pilot frequency and then monitors the amplitude of this frequency. Any change in signal level is fed back to the Bode equalizer. It is assumed that the encountered signal level changes are due to changes in cable attenuation and hybrid output associated with a change in temperature. The Bode equalizer then changes its insertion loss to maintain a constant output level.
3-16 Amplifier Setup Table 3-4 provides the AGC pad values for other output levels. Recommended pad values are shaded. Table 3-4 MB*/* AGC pad levels Amplifier ADU Control Range (dBmV) MB*/* AGC Pad (10 to 14 dB tilt) Minimum Level at 547.25 MHz Midpoint Level at 547.25 MHz Maximum Level at 547.
Amplifier Setup 3-17 Equipment required for return-path alignment includes: Full complement of JXP-*B pads and STARLINE Return Equalizers (SRE-*-*) Reverse signal generator — must produce at least one signal within the return bandpass and have variable output Return sweep or alignment equipment It is recommended that you: Do not use wire jumpers to bypass the SRE-*-* location Perform the return optical link set up before performing amplifier set up Specify reverse alignment design levels for a single carr
3-18 Amplifier Setup 13 Verify that the pad and equalizer values are similar to the map design values. You can verify proper return alignment by injecting a carrier, at the design level, into any amplifier at random. Proper alignment is achieved if you observe the reference level at the headend optical receiver output. Return levels used for alignment are not necessarily operational system levels.
Section 4 Bench Testing Motorola’s recommended procedure for placing a new MB*/* into service is to fully test it on the bench before it is field installed. There are specific alignment procedures that ensure proper functioning of all components and simplify final installation. If the MB*/* is properly aligned on the bench, only minor adjustments may be required in the field. The following subsections provide instructions to bench align the MB*/*.
4-2 Bench Testing Test Equipment and Connections The equipment typically used for testing the MB*/* consists of a network analyzer, such as the HP 8711, 8712 or 8713 series, a model 1076 sweep comparator, and a model 1901C display or equivalent. In addition, you need a 60/90 Vac bench power supply, a Motorola model SSP-PIN power combiner, and a variety of jumper cables, adapters, and fittings.
Bench Testing 4-3 Measuring Forward Gain This subsection provides instructions for measuring the full gain and the operational gain and flatness of the MB*/*. To measure the full gain of the amplifier: 1 Determine whether the power-supply jumper (J1) is positioned for LO or HI operation. 2 Connect the MB*/* to the test equipment as illustrated in Figure 4-1 and apply power. 3 Verify that the dc voltage is 24 V ± 0.4 V and re-install the input pad.
4-4 Bench Testing To measure the operational gain and flatness of the amplifier: 1 Perform steps 1 through 6 in Measuring Forward Gain above. 2 Estimate the ambient temperature and find the required gain reserve by referring to Table 3-3. Reduce the gain at the highest frequency by the amount given in the table. Example: The ambient temperature is 70°F. The table indicates that the required gain reserve is 5 dB. Reduce the gain by 5 dB.
Bench Testing 4 4-5 Measure the gain at the maximum return band frequency (example, 40 MHz for S-split). The amplifier gain is the sum of: the measured gain, the insertion loss of the return cable equalizer at the maximum return band frequency, the insertion loss of the power combiner, any pads installed in either the input or output pad locations, plus the cable simulator loss at the maximum return band frequency. The measured gain must meet advertised specifications for the return amplifier.
Section 5 Installation The field installation procedures presented in the following subsections assume that the amplifier was previously tested and bench aligned. Cable power and RF signal must be available on the system. Although it is preferable to have a full complement of channels available for balancing, you can adjust the MB*/* adequately with a limited number of channels. You can install the MB-HSG or MBP-HSG on a messenger strand (aerial) or on a pedestal.
5-2 7 Installation Check the ac voltage setting (jumper J1, Figure 2-10). J1 position Description LO The voltage must be greater than 38 Vac as read with a true rms voltmeter or 42 Vac when using a conventional, average reading, ac voltmeter. HI The voltage must be greater than 55 Vac when read with a true rms voltmeter or 61 Vac when using a conventional, average reading, ac voltmeter. 8 Check the dc voltage. Verify that it is between 23.6 V and 24.4 V and reinstall the input pad.
Installation 5-3 Pedestal Installation Pedestal installation is similar to the aerial installation with the exeception of temperature and mounting procedure. In an aerial installation, the cable and amplifier are subject to the same temperature. In contrast, pedestal installation provides a stable temperature environment for the buried cable while subjecting the elevated amplifier to higher temperatures.
Section 6 Operating Tips This section describes using amplifiers in lower frequency systems and in lower gain systems. Using Amplifiers in Lower Frequency Systems When using the MB*/* in 750 MHz or 550 MHz systems, you must consider the best method for handling the reduced bandwidth and channel-loading requirement. The following information helps you determine the best approach.
Appendix A Specifications Specifications are valid over the given bandpass and operating temperature range of −40°F to +140°F (−40°C to +60°C). Specifications are stated typical unless otherwise noted, and are subject to change. Refer to the Motorola BCS web site or contact your account representative for the latest specifications.
A-2 Specifications Model MB87S/XX* Specification Forward Amplifier Passband 52 through 870 MHz Gain Full 45 dB (with SFE-*-*) Operational 40 dB (with SFE-*-* and slope reserves) Flatness 52 through 870 MHz ±0.
Specifications A-3 Model MB75S/XG* Specification Forward Amplifier Passband 52 through 750 MHz Gain Full 45 dB (with SFE-*-*) Operational 40 dB (with SFE-*-* and slope reserves) Flatness 52 through 750 MHz ±0.75 dB maximum Level control, automatic Bode board using ADU/TDU Gain control Fixed pads, JXP-∗B Performance - reference frequency (MHz) 750/52 750/550/52 750/550/52 At typical output (dBmV) 47/37 45.5/48.5/41.
A-4 Specifications Model MB75S/XX* Specification Forward Amplifier Passband 52 through 750 MHz Gain Full 45 dB (with SFE-*-*) Operational 40 dB (with SFE-*-* and slope reserves) Flatness 52 through 750 MHz ±0.
Specifications A-5 RA-Kit/H Return Amplifier Parameter Specification Passband 5 through 40 MHz Gain, station (minimum) 20 dB (18 dB for M-split) Flatness ±0.
Appendix B Torque Specifications Torque specifications are valid for the MB*/*. In-lbs Torque Ft-lbs N •M 1/2 inch 120-144 10-12 13.6-16.3 5/16-18 1/2 inch 144 12.0 16.3 Test point plugs 5/8-24 1/2 inch 25-40 2.1-3.3 2.8-4.5 Seizure screw #8-32 3/16 inch or Phillips 12 1.0 1.4 Hybrid #6-32 Phillips 10-12 0.8-1.0 1.1-1.4 Chassis (electronics module) #10-32 5/16 inch 18-22 1.5-1.8 2.0-2.4 Chassis cover #6-32 1/4 inch or Phillips 10-12 0.8-1.0 1.1-1.
Abbreviations and Acronyms The abbreviations and acronyms list contains the full spelling of the short forms used in this manual.
475486-001 6/02 MGBI
