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5-2

●

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 fol-
lowing parts. (Shaded area of below Fig.)
— Around the magnetron
— The waveguide

●

After all components, including the outer panels,

are fully assembled, measure for microwave ener-
gy leakage around the door viewing window, the
exhaust opening and air inlet openings.

●

Microwave energy leakage must not exceed the

values prescribed below.

Leakage with the outer panels removed — less than 
5 mW/cm

2

.

Leakage for a fully assembled oven ("Before the latch
switch (primary) interrupted") with the door in a slight-
ly 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, oth-
erwise 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 ener-

gy interruption or microwave energy blocking
device, record the measured values for future refer-
ence. 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.

5-3

●

Microwave power output measurement is made

with the microwave oven supplied at its rated volt-
age 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
190 mm.

●

The oven and the empty vessel are at ambient tem-

perature 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 shelf 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 select-
ed so that the maximum difference between the
final water temperature and the ambient tempera-
ture is 5°K.

●

The microwave power output P in watts is calculat-

ed 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 2 sec.)

●

The water is stirred, to equalize temperature

throughout the vessel, prior to measuring the final
water temperature.

●

Stirring devices and measuring instruments are sel-

ected in order to minimize addition or removal of
heat.

4187 (

∆

T)

T

Water Load

Turn Table

1) Disconnect power supply cord from the outlet.
2) Remove the screws from the rear section. The out

case must be moved backward to the lifted off.

1) Remove the out case.
2) Disconnect two terminals from the noise filter assy

and remove one screw of the earth terminal.

CAUTION: DISCHARGE HIGH VOLTAGE

CAPACITOR BEFORE SERVICING

(refer to page 2-1)

1) Disconnect the wire leads and connectors from

the PCB ASSEMBLY.

2) Remove two screws securing the control panel to

the front plate and lift up the control panel.

3) Remove the control panel.

5-4

1) Remove two screws securing the hinge plate-U to

the oven cavity.

2) To remove the door, tilt the top of the door towards

you and lift the door up.

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

primary switch, monitor switch and secondary
switch operates normally.

2. After replacing the door, check for microwave

energy leakage with a survey meter.
Microwave energy must be below the limit of
4mW/cm

2

., (With a 275ml water load).

NOTE: 
Do not lose the spacer at the lower hinge and upper
hinge. When mounting the door assembly to the oven
assembly, be sure to adjust the door assembly paral-
lel to the chassis by moving the upper hinge and
lower hinge. Also adjust so that the door has no play
between the inner door surface and oven frame
assembly. If the door assembly is not mounted prop-
erly, 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 H.V capacitor.

3) Remove the screws holding the high voltage trans-

former to the base plate.

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

asm and H.V capacitor.

3) Remove the two screws holding the suction guide

assembly to the oven cavity.

4) Remove the two screws holding the fan motor

assembly to the suction guide asm.

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

asm and H.V capacitor.

3) Remove the screw holding the high voltage capac-

itor bracket and terminal of high voltage diode.

Hinge Plate-U

Fan Motor Asm

Suction
Guide

H.V. Capacitor

H.V. Transformer

5-5

1) Disconnect the leadwire from relay, oven lamp 

and thermostat.

2) Remove the mounting screws to the magnetron.
3) Bend the air duct flange front with a long nose 

pliers.

4) Rotate oven lamp anticlockwise and lift it up.

1) Disconnect the leadwire from high voltage trans-

former and high voltage capacitor.

2) Carefully remove the mounting screws holding the

magnetron and the waveguide.

3) Remove the magnetron assembly until the tube is

clear from the waveguide.

NOTES
1. When removing the magnetron, make sure its

dome does not hit any adjacent parts, or it may be
damaged.

2. When replacing the magnetron, be sure to install

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

3. After replacing the magnetron, check for micro-

wave energy leakage with a survey meter around
the magnetron. Microwave energy must be below
the limit of 5mW/cm

2

. (With a 275 ml. water load).

Make sure that gasket is rigidly attached to the
magnetron. To prevent microwave leakage, tight-
en the mounting screws properly making sure
there is no gap between the waveguide and the
magnetron.

1) Remove the turntable.
2) Remove the turntable shaft VERY CAREFULLY

with a slotted screwdriver.

3) Lay the unit down on its back.
4) Remove the Base plate cover.

The Base plate cover is easily removed by
unscrewing the one screw with a driver. 

5) Unscrew the screw securing the turntable motor to

the body, and the motor is removed.

6) After repairing the motor, fit the base plate cover to

the baseplate.

NOTES
1. Remove the wire leads from the turntable motor

VERY CAREFULLY with long nose pliers.

2. Be sure to grasp the connector, and not the wires

when removing.

Turntable Motor

Wire Leads

Air Duct

Waveguide

Dome

Magnetron
Gasket
Magnetron

Magnetron