Tait TM9100 - Fitting the Main-Board Assembly to the Chassis

TM9100 Service Manual Disassembly and Reassembly 133
© Tait Electronics Limited August 2005
Fitting the Main-
Board Assembly to
the Chassis
The circled numbers in this section refer to the items in Figure 5.3 on
page 127. This figure shows the 50W/40W configuration.
1. With the 50W/40W radio, the L-shaped gap pad
1) must be replaced
each time the main-board assembly
F is removed from the chassis G:
■ Remove any residue of the old gap pad from the audio-PA area on
the underside of the main board (refer to Figure 5.6 on page 131)
and the L-shaped ridge of the chassis (refer to Figure 5.3 on
page 127).
■ Peel off the transparent film on one side of the gap pad and evenly
press the gap pad on the L-shaped ridge of the chassis.
■ Peel off the transparent film on other of the gap pad.
2. If the thermal paste on the heat-transfer block or the underside of the
main board has been contaminated, new thermal paste must be
applied:
■ Remove any residue of the old thermal paste from both contact
surfaces.
■ Use Dow Corning 340 silicone heat-sink compound
(IPN 937-00000-55).
Important Ensure that no bristles from the brush come loose and
remain embedded in the paste. The paste needs to be
completely free of contaminants.
■ Use a stiff brush to apply 0.1cm
3
of thermal paste on the heat-
transfer block (refer to Figure 5.3 on page 127).
■ Use a stiff brush to apply 0.01cm
3
of thermal paste on the
audio-PA heat sink of the chassis (refer to Figure 5.3 on page 127)
3. Place the main-board assembly
F in position in the chassis G.
4. Loosely screw in the two screws
I through the heat-transfer block by
hand.