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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

• When you replace the magnetron, measure microwave

energy leakage before the out case is installed and
after all necessary components are replaced or
adjusted.
Special care should be taken in measuring the
following parts. (Shaded area of below Fig.)
— Around the magnetron
— The waveguide

• After all components, including the outer case, are fully

assembled, measure for microwave energy leakage
around the door viewing window, the exhaust opening
and air inlet openings.

• Microwave energy leakage must not exceed the values

prescribed below.

NOTES:
Leakage with the outer case removed - less than 
5 mW/cm

2

.

Leakage for a fully assembled oven (“Before the latch
switch (primary) is interrupted”) with the door in a slightly
opened position - less than 4 mW/cm

2

.

• Do not exceed meter full scale deflection.
• The test probe must be removed no faster than, 

1 inch/sec (2.5 cm/sec) along the shaded area,
otherwise a false reading may result.

• The test probe must be held with the grip portion of the

handle.
A false reading may result if the operator’s hand is
between the handle and the probe.

• When testing near a corner of the door, keep the probe

perpendicular to the surface making sure the probe
horizontally along the oven surface, this may possibly
cause probe damage.

• After adjustment and repair of any microwave energy

interruption or microwave energy blocking
device, record the measured values for future
reference. Also enter the information on the service
invoice.

• Should the microwave energy leakage not be more

than 4 mW/cm

2

after determining that all parts are in

good condition, functioning properly and genuine
replacement parts which are listed in this manual have
been used.

• At least once a year, have the electromagnetic energy

leakage monitor checked for calibration by its
manufacture.

5-2

• Microwave power output measurement is made with

the microwave oven supplied at its rated voltage and
operated at its maximum microwave power setting
with a load of (1000 ± 5)g potable water.

• The water is contained in a cylindrical borosilicate

glass vessel having a maximum material thickness of
3 mm and an outside diameter of approximately
190mm.

• The oven and the empty vessel are at ambient

temperature prior to the start of the test.

• The initial temperature (T1) of the water is (10±2)°C. It

is measured immediately before the water is added to
the vessel. After addition of the water to the vessel,
the load is immediately placed on the center of the
turntable which is in the lowest position and the
microwave power switched on.

• The time T for the temperature of the water to rise by a

value 

∆

T of (10±2)°K is measured, where T is the time

in seconds and 

∆

T is the temperature rise. The initial

and final water temperatures are selected so that the
maximum difference between the final water
temperature and the ambient temperature is 5°K.

1) Disconnect power supply cord from the outlet.

2) Remove the screws from the rear and along side

egges of the case. 
The ouer case must be moved backward to the lifted
off.

1) Remove the out case.

2) Disconnect two terminals, and remove one screw of

the earth terminal.

CAPACITOR BEFORE SERVICING
(refer to page 5)

1) Disconnect the leadwire from the PCB SUB ASS'Y.

2) Remove the screws for the earth and securing the

control panel.

3) Lift control panel ASS'Y from the oven by the tab

unhooked.

• The microwave power output P in watts is calculated

from the following formula:

P =

is measured while the microwave generator is
operating at full power. Magnetron filament heat-up
time is not included. (about 3 sec.)

• The water is stirred to equalize temperature throughout

the vessel, prior to measuring the final water
temperature.

• Stirring devices and measuring instruments are

selected in order to minimize addition or removal of
heat.

5-3

Water Load

Turn Table

4187x(

∆

T)

T

1) Open the door.
2)  Remove the choke cover cap very carefully with a

flat-blade screwdriver.

3) Lift up and push the door.

1. After replacing the door, be sure to check that the

primary switch, monitor switch, and secondary switch
operate normally.

2. After replacing the door, check for microwave energy

leakage with a survey meter. Microwave energy must
be below the limit of 5 mW/cm.(with a 275 ml water
load)

3. When mounting the door assembly to the oven

asembly, be sure to adjust the door assembly parallel
to the chassis. Also adjust so the door has no play
between the inner door surface and oven frame
assembly. If the door assembly is not mounted
properly, microwaves may leak from the clearance
between the door and the oven.

1) Discharge the high voltage capacitor.
2) Disconnect the leadwire from magnetron, high voltage

transformer, and capacitor.

3) Remove the screw holding the high voltage

transformer to the baseplate.

1) Discharge the high voltage capacitor.
2) Disconnect the leadwire from fan motor, noise filter

and high voltage capacitor.

3) Remove the two screws holding the the suction guide

ASS'Y to the oven cavity and remove the high voltage
diode earth screw.

4) Remove the screw of the capacitor bracket.
5) Remove the two screws holding the fan motor ASS'Y

to the suction guide ASS'Y

1) Discharge the high voltage capacitor.
2) Disconnect the leadwire from  fan motor, noise filter

and high voltage capacitor.

3) Remove the screw holding the suction guide ASS'Y to

the oven cavity and remove the high voltage diode
earth screw.

4) Remove the screw holding the high voltage capacitor

bracket.

5-4

Fan Motor ASSY

H. V.
Transformer

H . V .
Diode

Suction
Guide

H. V.
Capacito

Door seal plate

Remove choke cover cap

Remove door