RF. Amplifier Maintenance The HMS amplifier assembly consists mainly of & power amplifier sub assembly and a power supply, as shown on the block diagram 102152. In most cases, field maintenance of the HMS amplifiers should not be attempted. However, if disassembly for repair is required; major components of the amplifier asses blues can he easily removed and replaced. Removal of the Rf Amplifier: | The RF amplifier assembly can be removed using the following steps: 1.
METERING AND TEST POINTS ON CONTROLLER ASSEMBLY The following signals and voltages are indicated on the front panel meter, a liquid crystal display. The voltage to be monitored is delectable via front panel momentary contact tangle switch. The display has two lines of text. The top line indicates the parameter to be measured while the bottom line indicates the measured value and its units. Therefore front panel drawing in the Illustrations section forth location of the meter and switch.
Metering and Test Points {Cont} INDICATOR FUNCTION/CHARACTERISTIC 0. Steady green light indicating that DC is being supplied to. the unit; SWR Lamp oii visa Flashing red alarm when deputation SWERVE is tov high. TEMP Lamp. un Flashing red alarm when amplifier chassis is: too warm, LOLLOP LAND ove vn esa Flashing red alarm when RE: output power is: too low; FANS Lamp. Flashing red alarm when a fan is not operating.
Monitor Signals High Power VHF/AM Amplifier Signal FUNCTION: [PIN Definition SOURCE MODE VOLTAGE INS 2 Input RF Power | Source R = 8K Analog 5V =100 VESSEL 4 B Amp. Voltage | Source R= 5K Analog QV =1V IBS 5 B Amp: Voltage | Buffer Amp. Analog CAV =A LOLLOP 6 Low Power pe Rooter: Series Active Low 18 Max. SWR 7. | Sanding Wave | Open collector, Series | active Low [15V Max. TEMP 8 oe rate: Open collector, Series | active Low |15V Max. PFS 10. [Forward Power | Source R = 5K Analog BV.
OPERATOR ADJUSTMENT A display contrast adjustment is provided on the front panel, between the LCD display and the mister select switch. This is a ten yurt pot, Other operator adjustments are accessible through the rear panel of the Control Unit. These are potent meter VR3 through VRZ. Their functions are as follows: REF, DESIGN. FUNCTION/ADJUSTMENT MR as SWR threshold set to determine the alarm level for the front panel i indicator. V. Determines the threshold for a valid PTT sensing level.
OPERATOR ADJUSTMENTS: Cont) RF Adjustments VRE Toggle the front panel switch until the top line of thé display reads FWD PWR. With the proper RF termination still in place: monitor the RF forward power.output on a cab rated power meter. Set the input drive level to provide nominal power output Stadium VRE so that the front panel meter is in agreement with the calibrated power meter, VR? Toggle the front panel switch until the top line of the display reads FWD PWR.
WARRANTY TPL COMMUNICATIONS has tested and found this unit to function properly and to operate within the parameters of its Stated specifications. TPL COMMUNICATIONS warrants that this product is free from defects in material and workmanship. If found 0 be defective within two (2) years from the date of purchase. TPL, at its discretion, will repair or replace the unit at no cost provided the unit is delivered to the factory intact.