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This device is to be serviced only by properly qualified service personnel.
Consult the service manual for proper service procedures to assure continued safety operation and for precautions to be
taken to avoid possible exposure to excessive microwave energy.

A) Do not operate or allow the oven to be operated with the door open.

B) Make the following safety checks on all ovens to be serviced before activating the magnetron or other

microwave source, and make repairs as necessary; (1) interlock operation, (2) proper door closing,  (3)

seal and sealing surfaces (arcing, wear, and other damage), (4) damage to or loosening of hinges and

latches, (5) evidence of dropping or abuse.

C) Before turning on microwave power for any service test or inspection within the microwave generating

compartments, check the magnetron, wave guide or transmission line, and cavity for proper alignment,

integrity, and connections.

D) Any defective or misadjusted components in the interlock, monitor, door seal, and microwave generation

and transmission systems shall be repaired, replaced, or adjusted by procedures described in this manual

before the oven is released to the owner.

E) A microwave leakage check should be performed on each oven prior to release to the owner.

DO NOT BECOME EXPOSED TO RADIATION FROM THE MICROWAVE GENERATOR
OR OTHER PARTS CONDUCTING MICROWAVE ENERGY.

Tools normally used for TV servicing are sufficient.

Standard tools are listed below.

●

Diagonal pliers

●

Long nose pliers

●

Cross head screwdriver

●

Wrench (size 5 mm)

●

Nutdriver (size 5 mm)

●

Adjustable wrench

●

Soldering iron

●

Solder

●

Vinyl insulation tape

●

Polishing cloth

●

Be sure to check a microwave emission prior to 
servicing the oven if the oven is operative prior to 
servicing.

●

If the oven operates with door open, the service per-
sonnel should;
—Tell the user not to operate the oven

●

The service personnel should check all surface and
vent openings for microwave emission testing.

●

Check for microwave energy leakage after every 
servicing. The power density of the microwave 
radiation leakage emitted by the microwave oven
should not exceed 4 mW/cm

2

.

And always start measuring of an unknown field to
assure safety for operating personnel from radiation
leakage.

NOTE: The standard is 5 mW/cm

2

while in the 

customer’s home. 4 mW/cm

2

stated here is 

manufacturer’s own voluntary standard for units in 
customer’s home.

●

Microwave Survey Meter

●

600cc glass beaker

●

Glass thermometer 100°C

●

TESTER (VOLTS-DC, AC, Multmeter)

●

Microwave survey meter
—Holaday H1-1500, Hi-1501
—Narda 8100, 8200

●

Inch scale

●

600 cc non conductive material beaker (glass or 
plastic), inside diameter: approx. 8.5cm (31/2 in.)

●

Cylindrical and made of borosilicate glass vessel max.
thickness: 3mm
outside diameter: approx. 190mm
height: approx. 90mm

●

Glass thermometer: 100°C or 212°F (1˚C scale)

●

Pour 275 ± 15cc of 20°C ± 5°C water in a beaker
which is graduated to 600 cc, and place the beaker on
the center of the turntable.

●

Set the energy leakage monitor to 2,450 MHz and use
it following the manufacturer’s recommended test 
procedure to assure correct result.

●

When measuring the leakage, always use the 2 inch
(5cm) spacer supplied with the probe.

●

Operate the oven at its maximum output.

●

Measure the microwave radiation using and elec
tromagnetic radiation monitor by holding the probe
perpendicular to the surface being measured.

5-1

Move probe along shaded area.

Probe scanning speed;
Less than 2.5 cm/sec

5-10

Antenna

Gasket

Filament
Terminals

Chassis

NOTE : When testing the magnetron, be sure to install the magnetron gasket in

the correct position and be sure that the gasket is in good condition. 

Measure the resistance.
(Multi-meter scale : Rx1000) 

●

Terminal to termonal.

Normal : Momentary 

indicates several
ohms, and then
gradually returns to
infinite.

Normal : 

∞

.

Normal : Continuity.
Abnormal : 

∞

.

Normal : 

∞

.

Abnormal : Continuity.

HIGH VOLTAGE
CAPACITOR

HIGH VOLTAGE
DIODE

NOTE :
Some inexpensive
meter may indicate
infinite resistance in
both direction.

Measure the resistance.
(Multi-meter scale : Rx1000) 

●

Terminal to case.

Measure the continuity (Forward).
(Multi-meter scale : Rx10000) 

Measure the continuity (Reverse).
(Multi-meter scale : Rx10000) 

5-11

BK

WH

RD

GN

1
2
3
4

connector

Shield Wire

NOTE : If the fuse is blown, check the primary, the secondary, and the monitor

switches, H.V.D. and H.V.C. before replacing the fuse.
If the fuse is blown by improper switch operation replace the defective
switch and the fuse at the same time.
Replace just the fuse if the switches operate normally.

Check for continuity of the switch with a
Multi-meter.

Normal

Abnormal

0°c~Approx 150°C

Approx 150°C

FUSE
(Wire leads removed.)

SENSOR

(Wire leads removed)

OVEN THERMOSTAT
MAGNETRON
THERMOSTAT

Measure the resistance.

1 and 2

Approx. 470K

Ω

1 and 3

Approx. 1.5K

Ω

1 and 4

Approx. 2.0K

Ω