Replacement Of Major Parts - JRC JMA-7710-6 Instruction Manual

8.4

Replacement of Major Parts

Before replacing parts, be sure to turn off the main power supply, otherwise you will get
an electric shock and replaced parts will get out of order.
Before replacing the magnetron, discharge the high voltage circuit, otherwise you will get
an electric shock.
When bringing your hand(s) close to the magnetron, remove your wrist watch, otherwise
your wrist watch will break because the magnetron is a strong magnet.
Let two or more workers replace the CRT.
It is heavy, dropping it may injure you.
When removing wiring of the high voltage pack from the CRT, never touch the core wire
(metal parts) of the CRT anode cap with your bare hands, otherwise you will get an electric
shock.
Attention
G When removing wiring, touch the terminal with the metal part of a screwdriver while keeping the
terminal in contact with the frame.
[Replacement of Magnetron V201 (10kW : NKE-1055)]
Replace the magnetron as follows:
(1) Loosen the four A scanner unit screws (see Fig. 8.1).
(2) Lift the scanner unit to open the pedestal (see Fig. 8.1).
(3) Loosen the four B screws fixing the transceiver unit (see Fig. 8.1).
(4) Move the transceiver upward to remove it from the pedestal.
(5) Remove the four C screws and loosen the two D screws to remove the sender from the transceiver (Fig.
8.2).
(6) Loosen the five E sender screws to remove the sender cover (see Fig. 8.2).
(7) Loosen the four F screws and remove the pulse transformer cover (see Fig. 8.4).
(8) Remove the cable G between the pulse transformer and magnetron from the transformer side using a
soldering iron (see Fig. 8.4).
(9) Remove the four H screws fixing the magnetron, the seven I screws fixing the PCB and the four J
screws fixing the IC to remove the magnetron (see Fig. 8.3).
(10) For remounting the magnetron, follow the opposite procedure.
In this case, properly connect the lead wires.
WARNING
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