JMA-5300MkIIsm

INDEX > 4.Replacement Procedure > 4.4 Scanner Unit NKE-2103 (JMA-5312-6/6HS)
4.4.5 Modulator Circuit replacement (CME-363)
[Required tools]
• A Phillips screwdriver for 4 mm screws
• A Phillips screwdriver for 5 mm screws
• Tools for removing the cover from the scanner unit
(see Section 4.4.1, page 4-46)
[Replacement procedure]
1) Open the upper cover (see Section 4.4.1,
page 4-46) to remove the transmitter-receiver
unit (see Section 4.4.2, page 4-47).
4
2) Remove the screws (nine M4 screws) holding
the modulator circuit board in place and
remove the cables connected to the
modulator circuit board, then replace the
modulator circuit board.
If you are reusing the heat radiation plate on the
modulator, be sure to install the thermal
insulation sheet between TR17, TR18, and the
heat radiation plate so that it is straight.
Remove the
nine screws
(M4).
3) After replacing the Modulator circuit board,
assemble the unit in the reverse order of the disassembly procedure.
Do not forget to tighten the screws and connect the cables.
[Check points]
1) Turn on the radar power supply. After the countdown is completed, start emission and
check that the radar image appears without error.
Transmit radar signals on a long range (48NM) and open the test menu to make sure the
magnetron current is shown between the 4th and 7th calibration markings (see Section 6.1.1,
page 6-1).
4-51