HP 8112A Operating, Programming And Servicing Manual page 376

B-42 Backdating
Figure B-12. Exploded view of HP 8 1 1 2A rear frame
1 .
Turn off the instrument and disconnect the power cord.
2. Disconnect and remove the microprocessor board A3 and
the control board A2 (Note which cables connect to which
connectors/pins in order to make re-assembly simple) .
3. Remove the bottom cover from the instrument .
Remove the heatsink, located in front of the fan, by unscrewing
the two screws A.
4. Remove the two screws B , holding the rear frame to the
brackets.
5 . Remove the four screws C, holding the rear frame to the
side frames.
6. Remove the rear frame by pulling it gently backwards.
If necessary, the fan can be removed by unscrewing screws D.
Similarly, the transformer can be removed by unscrewing screws
E.