6-2 REMOVING AND
REPLACING THE
CHASSIS COVERS
Troubleshootingprocedures require removal of the top cover. Replace-
ment of some 682XXB/683XXB assemblies and parts require removal
of all covers. The following procedure describes this process.
Preliminary Disconnect the power cord from the unit.
Procedure Remove and replace the chassis covers as follows:
Step 1 Using a Phillips screwdriver,remove the
screws and the two feet from the top cor-
ners at the rear of the instrument (Figure
6-1).
Step 2 Remove the screw that fastens the top
cover to the chassis. (The screw is located
at the rear of the instrument.)
Step 3 Slide the top cover out along the grooves
in the chassis and set it aside.
Step 4 Turnthe instrument over so that the bot-
tom cover is on top.
Step 5 Remove the screws and the two feet from
the bottom corners at the rear of the in-
strument.
Step 6 Remove the screw that fastens the bottom
cover to the chassis. (The screw is located
at the rear of the instrument.)
Step 7 Slide the bottom cover out along the
grooves in the chassis and set it aside.
Step 8 Turnthe instrument over to return it to
the upright position.
Step 9 Remove the screws and the carrying han-
dle from the side handle cover.(The two
screws fastening the carrying handle
through the side handle cover to the chas-
sis are accessable by lifting up the rubber
covering at the each end of the handle.)
Step 10 Remove the screw that fastens the side
handle cover to the chassis. (The screw is
located at the rear of the instrument.)
Step 11 Remove the side handle cover and set it
aside.

6-4 682XXB/683XXB MM

REMOVAL AND CHASSIS

REPLACEMENT PROCEDURES COVERS

NOTE
The screws with green heads have
metric threads. When it becomes
necessary to replace any of these
screws, always use the exact re-
placement green-headed screws
(ANRITSU P/N 2000-560) to avoid
damage to the instrument.