Tait TM8000 Series, Руководство по обслуживанию

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TM8100 Mobile Radio Service Manual Disassembly and Re-assembly of Radio 145
May 2004 © Tait Electronics Limited
Install Main-board
Assembly —
Apply Thermal Paste
If the main-board assembly needs to be installed, first replenish the
thermal paste on the heat-transfer block and on the screw boss on the
floor of the chassis:
1. Thermal paste is required on the area of the heat-transfer block
shown in
Figure 6.9 . This area constitutes the contact area
between the main-board assembly and the chassis.
2. Inspect the area on the heat-transfer block requiring thermal paste,
as well as the corresponding area on the chassis. If the residual
paste has been contaminated with dirt, clean off the paste.
3. Obtain 0.1 cm
3
of thermal paste. Use Dow Corning 340 silicone
heat-sink compound (IPN 937-00000-55) or the equivalent.
4. Use a stiff brush to apply the paste in a thin film to the required
area on the heat-transfer block. Ensure that no bristles from the
brush come loose and remain embedded in the paste. The paste
needs to be completely free of contaminants.
5. Thermal paste is also required on the screw boss in contact with
the PCB. The area is shown in
Figure 2.11 . Inspect the area, as
well as the corresponding area on the PCB. If the residual paste
has been contaminated with dirt, clean off the paste.
6. Replenish the paste on the screw boss as described in Steps 3 and
4. The amount of paste required is about one-tenth of that used
for the heat-transfer block.
Table 6.3 Summary of the torque values for the fasteners used in TM8100 mobile radios
Description of screws Drive type Quantity
Torque
(N·m) Torque
(lbf·in)
Screws for control-head board Torx T10 3 0.56 5
Screws for lid of radio body Torx T20 4 2.5 22
External screws for main-board assembly Torx T20 2 2.5 22
Internal screws for main-board assembly Torx T10 5 1.9 17
Screws for copper plate Torx T10 3 1.7 15
Screws for power connector Torx T10 2 0.34 3
Lock-nuts for auxiliary connector 3/16-inch socket 2 0.90 8
Hexagonal nut of RF connector Long-reach socket 1 1.7 15