Tektronix WFM5250, Service Manual

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Removal and Replacement Procedures
Fan/Bracket Disassembly 1. Disconnect the fan cables from J7 and J8 on the CPU board. These connectors
are locked in place; push the release tab in the middle to unlatch them.
When reinstalling, attach the fan cables before seating the CPU board on the
main chassis; make sure to push the fan cable plugs into the connectors until
they snap into place. Then seat the CPU board into the main chassis and drape
the fan bracket and cables over the right side of the front panel to keep them
out of the way. (You’ll need to reinstall the Video I/O board and the FPGA
board before reinstalling the fan bracket.)
2. Separate the fan bracket from the main chassis by pulling the cables out
through the slots.
3. Remove the two pan-head 40 X 1.500 T10 screws from the front of each fan.
4. When reassembling, place the fans so that the labels are facing the fan bracket.
Insert the screws in the holes shown. (See Figure 6.)
Figure 6: Fan screw placement
CPU board 1. Using a
3
/
16
" nut driver, remove the three 0.276 L spacer posts that secure
the CPU board to the chassis. When reinstalling, tighten these to 0.62 N-M
(5.5 in/lb).
2. Remove the one pan-head 40 X 0.187 T10 screw that secures the CPU board
to the main chassis. When reinstalling, put the screw in the lower left corner
of the board. Tighten this screw to 0.62 N-M (5.5 in/lb). (See Figure 7.)
3. Disconnect the front panel cable from J1 on the CPU board. Then disconnect
the backlight cable from J5 on the CPU board. Pull these plugs straight away
from their connectors, to prevent damage.
4. Move the CPU board away from the main chassis and place it on the
static-free work surface.
WFM5250 Waveform Monitor Service Manual 31