Orban OPTIMOD-FM 8700, Operating Manual

Page: 281 / 390

OPTIMOD-FM DIGITAL MAINTENANCE
4-5
C) Unplug any ribbon cables from the Display Interface Board, which now can be
removed completely. Refer to step (8.C)to disconnect the 33-conductor ribbon
cable to J103.
12. Removing the Base Board.
You must have completed steps 9, 10, and 11 first.
A) Make sure that AC power is disconnected from the 8700i.
B) Remove the three power ribbon cables from the power supply and dress them
away from the Base Board.
C) Using a 3/16-inch nut driver, remove the two jackscrews and lock washers
holding the DB25 connector to the rear panel.
D) Remove the four Phillips screws and four standoffs holding the Base Board to
the bottom of the chassis.
E) Verify that all connectors have been removed.
F) Remove the Base Board.
13. Reinstalling the I/O Board and DSP board:
Referring to steps 2 and 3, follow the instructions in reverse.
14. Reinstalling the Base Board.
Referring to step 12, follow the instructions in reverse.
Note that you cannot replace the RS-232 board, Display Interface Board, and the
CPU board until you have replaced the base board.
15. Reinstalling the Display Interface Board.
Referring to step 11, follow the instructions in reverse.

To avoid bent pins or other damage, verify that all connector pins are aligned
before applying force.

Verify that pin one of the ribbon cables (red stripe) is oriented correctly. Pin 1
is indicated by the number “1” or a square pad.

Note that you cannot replace the CPU board until you have replaced the Base
Board and the display interface board.
16. Reinstalling the CPU Board:
To avoid bent pins or other damage verify that all connector pins are aligned be-
fore applying force.
Referring to step 10, follow the instructions in reverse.
17. Reinstalling the RS-232 Board:
Referring to step 9, follow the instructions in reverse.