14: Maintenance
14-8
PRC1099A-MS
Remove and
Replace the
Audio/Filter
Board
The Audio/Filter board is mounted under the Power Amplifier and Antenna
Tuner boards. You have to remove some retaining screws and lift the tray with
the Power Amplifier and Antenna Tuner boards.
To remove and replace the Audio/Filter board from the chassis:
1. Disassemble the radio chassis (refer to “Chassis Disassembly” on page
2. Remove the two retaining screws on the Power Amplifier and Antenna
Tuner modules tray as shown in Figure 14-6 on page 14-7.
3. Disconnect the white-wire antenna connection from the Antenna
Tuner board to the front panel
ANT
connector. This allows the
mounting tray to swing fully open.
4. Disconnect the two RF coax connectors from the underside of the
Power Amplifier and Antenna Tuner boards and the two onboard RF
coax connectors J8 (RX OUT) to the Mixer board. Also, disconnect J7
(BFO INPUT) from the Synthesizer board.
5. Disconnect the multi-pin connectors (J4, J5, and J6) at the side of the
Audio/Filter board.
Removing the 1650 kHz IF board (refer to “Remove and Replace the
1650 kHz IF Board” on page 14-7) makes accessing, disconnecting,
and reconnecting connectors J4, J5, and J6 on the Audio/Filter board
much easier.
J7
J1
J2
J3
Mounting
Screw
Mounting
Screw
Mounting
Screw
Mounting
Screw
Mounting
Screw
J6
J5
J4
J8