Replacing The Interconnect Boards - Tait TB8100 Service Manual

10.8

Replacing the Interconnect Boards

Removal
Refitting
192 Power Amplifier Board Replacement
Important
Make sure the heatsink compound is clean. Any objects
caught in the heatsink compound underneath the resistor
which prevent effective heatsinking may cause it to fail.
7. Refit the ground tag(s) and secure the resistor to the heatsink with the
4–40 UNC screw(s). If there are two screws, progressively tighten
each screw, alternating from side to side, to the correct torque.
8. Solder the ground tag(s) and resistor tab to the PCB. While soldering
the resistor tabs, gently press down on them with a ceramic trimming
tool to ensure they are as close as possible to the pads on the PCB.
9. Retorque the 4–40 UNC screws after eight hours of operation.
10. Refit the cover.
Refer to "Power Amplifier Disassembly and Reassembly" on page 173
details on removing and refitting the cover, and for screw torque settings.
1. Remove the cover.
2. Desolder the RF links connecting the board to any adjacent boards.
You may need to move the +28VDC power feed wire out of the way
first.
3. Remove the M3 Torx screws securing the board to the heatsink.
4. Carefully lift the board directly upwards off the locating pins and
remove it from the heatsink.
1. To refit the board, follow the removal instructions in reverse order.
Note
Before tightening the screws, press the board down over the locat-
ing pins so that it is firmly seated against the heatsink. Then
tighten the M3 Torx screws to the correct torque.
TB8100 Service Manual
© Tait Electronics Limited September 2006
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