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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

personnel 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 (3

1

/

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 deg 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

electromagnetic 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

HIGH VOLTAGE
CAPACITOR

Antenna

Gasket

Filament
Terminals

Chassis

Normal : Momentary indicates

several ohms, and
then gradually
returns to infinite.

Normal : 

∞

.

: 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 : R x 1000) 
• Terminal to termonal.

Measure the resistance.
(Multi-meter scale : R x 1000) 
• Terminal to case.

Measure the continuity (Forward).
(Multi-meter scale : R x 10000) 

Measure the continuity (Reverse).
(Multi-meter scale : R x 10000) 

Normal : 

∞

.

Abnormal : Continuity.

Normal : Continuity.
Abnormal : 

∞

.

HIGH VOLTAGE
DIODE

Some inexpensive
meter may indicate
infinite resistance in
both direction.

5-11

HEATER ELEMENT
(Wire leads removed)

FUSE
(Wire leads removed.)

Normal

Abnormal

0°c~Approx 150°C

Approx 150°C

OVEN THERMOSTAT
MAGNETRON
THERMOSTAT

Normal : 

• Grill heater

Approx. 40.7 

Ω

(at 20~30°C)

Normal : more than 0.5M 

Ω

Measure the resistance with 500V-100M

Ω

insulation resistance meter.

Measure the resistance.
(Multi-meter scale : R x 1) 

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

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.

NOTE : Make sure heater is fully cooled when tested.

5-12

GRILL HEATER
(Wire leads removed)

SOLENOID

RECTIFIRE ASM:
VOLTAGE FOR
SOLENOID

CIRCULATION MOTOR
(Wire leads removed)

NOTE:
*(     ) = WIRE COLOR

Normal : COM-230V : Approx. 150 

Ω

COM-24V : Approx. 20 

Ω

Abnormal : Infinite or several ohm.

Normal : Approx. 200~300 

Ω

Abnormal : Infinite or several

ohm.

Normal : Approx. 134 

Ω

Abnormal : Infinite or several ohm.
DC : 24V

24V
(BN)

COM
(YL)

230V(BL)

AC 28V

DC 24V

INPUT

OUT PUT

BN

YL

Measure the resistance.
(Multi-meter scale : R x 1) 

Measure the resistance.
(Multi-meter scale : R x 1)