Sharp R-22AM Service Manual page 10

R-22AM
R-23AM
R - 2 3 A T
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.
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
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.
MICROWAVE VARIABLE COOKING (for R-22AM
and R-23AM)
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.
48 sec. ON
100%
26sec. ON
50%
12 sec. ON
20%
8 sec. ON
10%
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.
TWO MAGNETRON OPERATION SYSTEM
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.
T2: HIGH VOLTAGE
TRANSFORMER
H. V. FUSE
H. V. RECTIFIER
MG2: MAGNETRON (LOWER)
Figure B-1. High Voltage Circuit
COMMERCIAL
FREQUENCY
(50HZ)
POWER OUTPUT
BY MAGNETRON T1
POWER OUTPUT
BY MAGNETRON T2
Figure B-2. Operation of Magnetron
8
T1: HIGH VOLTAGE
TRANSFORMER
(REAR)
H. V. FUSE
H. V. RECTIFIER
MG1: MAGNETRON (UPPER)
OPERATION OF
MAGNETRON
(FRONT)