R-24AT (serv.man2). Complete - Sharp Home Appliance Service Manual (repair manual). Page 7

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power, the line voltage is supplied to the high voltage
transformers T1+T2 intermittently within a 48 second time
base through the contacts of the relays RY3+RY4.
The following levels of microwaves power are given.

NOTE: The ON/OFF time ratio does not exactly corre-

spond to the percentage of microwave power,
because approx. 3 seconds are needed for heat-
ing up the magnetron filament.

When the microwave oven is preset for variable cooking
power, the line voltage is supplied to the high voltage
transformers intermittently within a 48 second time base
through the contacts of the relays RY2+RY3.
The following levels of microwaves power are given.

NOTE: The ON/OFF time ratio does not exactly corre-

spond to the percentage of microwave power,
because approx. 3 seconds are needed for heat-
ing up the magnetron filament.

48 sec. ON

Number key   

44sec. ON

Number key 9

40 sec. ON

Number key 8

36 sec. ON

Number key 7

32 sec. ON

Number key 6

26 sec. ON

Number key 5

22 sec. ON

Number key 4

16 sec. ON

Number key 3

12 sec. ON

Number key 2

8 sec. ON

Number key 1

0 sec. ON

Number key 0

48 sec. ON

100% 

26sec. ON

50%

12 sec. ON

20%

8 sec. ON

10%

T1: HIGH VOLTAGE
      TRANSFORMER

 H. V. RECTIFIER

C1: H.V. CAPACITOR

MG1: MAGNETRON (UPPER)

(REAR)

 H. V. RECTIFIER

 H. V. FUSE

 H. V. FUSE

C2: H.V. CAPACITOR

MG2: MAGNETRON (LOWER)

T2: HIGH VOLTAGE
      TRANSFORMER

(FRONT)

COMMERCIAL
FREQUENCY
(50HZ)

POWER OUTPUT
BY MAGNETRON T1

POWER OUTPUT
BY MAGNETRON T2

OPERATION OF
MAGNETRON

Two magnetrons MG1+MG2 are equipped in order to get
higher microwave power output. The primary windings of
the high voltage transformers T1+T2 are connected so
that each magnetron can be oscillated alternatively ac-
cording to the frequency of the power supply. Refer to the
Figure B-1 and B-2.