Disassembly Procedure

LBI-39175A

To Remove the Unit from the Mounting Bracket

1.Remove Microphone, Power, and Accessory/Remote Control Cables, as required.

2.Remove the lock screws at the side of the radio unit, using a No. 20 TORX® driver.

3.Pull the radio, and remove the mounting bracket.

To Gain Access to the Circuitry for Servicing

RF Power Amplifier Module

1.Remove the waterproof cover on the bottom of the module, using #20 TORX® driver. Note that the four mounting screws are captive.

2.Remove the inner shield by pulling the attached handle.

Transceiver (TXRX) Module

1.Remove the waterproof top and bottom covers, using a #20 TORX® driver. Four cover mounting screws are located on the bottom of the module. The screws on the bottom cover are captive.

2.To expose the Logic/Audio/455 kHz IF circuitry, remove the shield on top of the module by pulling the attached handle.

3.To expose the Exciter/RX Front End circuitry, remove the shield on the bottom of the module by pulling the attached handle.

NOTE

The VCO/Synthesizer circuitry is exposed by removing the screws from the shield casting, also located on the bottom of the module. However, this is not recommended, except on extreme situations. If the shield is removed, it should be replaced using the exact screw torque and installation sequence given in LBI-38909.

Control Unit (Front Mounted)

1.Expose the Logic/Audio/455 kHz IF circuitry according to Steps 1 and 2 in Transceiver (TXRX) Module section.

2.Disconnect Flex Circuit PC2 from Connector J701, by carefully disengaging the locking tab from each side of the connector with a jeweler's screwdriver or tweezers. Use extreme care to avoid damaging the plating runs or surface-mounted components on the printed wire board (PWB) during this procedure.

3.Turn the radio upside down, and disengage the two mounting screws, using a #10 TORX® driver. Be sure to engage the screws in the captivation threads on the Transceiver chassis. Do this by pulling each screw upwards with tweezers or needle nose pliers,

while simultaneously turning the screw counterclockwise with the TORX® driver. See LBI- 38909 for details.

4.Disengage the control unit from the Transceiver chassis using a pivoting motion about the top edge of the Transceiver chassis.

5.Disengage the four captive screws on the rear cover, using a #10 TORX® driver. Slide the rear cover off the Front Panel Assembly, using care to avoid damaging the black "O-Ring" moisture gasket attached to the rear cover. Note that the Flex Circuit PC2 slides through a slot opening on the rear cover.

Control Head (Remote Mounting)

1.Disconnect Remote Control and Accessory cables, using a small flat bladed screwdriver.

2.Remove the two side mounting screws from the mounting bracket. Carefully remove the Control Head assembly from the bracket.