JRC JMR-92 Series Field Service Manual page 255

The magnetron is held by a hook, but be careful not to let it fall.
Use a non-magnetic screwdriver. If the magnetron comes into contact with any metal (tool),
its performance may deteriorate.
Step 4 Replace the modulation unit.
Remove the two screws (M5), loosen the five screws (M5) holding the modulation unit, and
replace it. After replacing the modulation circuit board, assemble the unit in the reverse order of
the disassembly procedure. Install the magnetron that was removed to the original position. Do not
forget to tighten the bolts or screws, and make sure that the cables are connected.
Remove two screws
Step 5 Operation check
After completing the replacement work, turn On the safety switch and check operation by
following the procedure below.
(1) Turn On the Display unit. After the preheat countdown is completed, start transmission
and check that the radar image appears without error.
Transmit the radio wave in long pulse range mode and open the service engineer menu
to check that the magnetron current stands between the 5th and 7th calibration markings.
This completes modulation unit replacement.
Loosen five screws
4-35 Chapter 4 Replacement procedure