TurboChef NGC-1007, Service Manual

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+(B)
-(C)
(A)
-4800 V
MAGNETRON VOLTAGE
0
- + -
+
2400
2400
VDC
4800
VDC
Current
Flow
TRANSFORMER OUTPUT VOLTAGE
+(B)
0
-(C)
(A)
-2400 V
+2400 V
-
- + +
2400
VDC
2400
Current
Flow
CAPACITOR CHARGES
ON POSITIVE VOLTAGE SWING
CHARGED CAPACITOR PLUS TRANSFORMER
ON NEGATIVE VOLTAGE SWING
F I G U R E
19: Voltage Doubler Circuit Theory of Operation
VOLTAGE DOUBLER THEORY OF OPERATION
Figure 19
1. The high-voltage transformer steps up the input
voltage to approximately 2400 volts peak (4800
volts peak to peak).
2. The high-voltage capacitor charges to 2400 volts
on the positive going voltage via the high volt-
age diode’s conduction.
3. The high-voltage transformer plus the charged
high-voltage capacitor supply down to -4800
volts to the magnetron when the voltage goes
negative. (high-voltage diode is back biased.)
4. The magnetron converts negative input voltage
(and current) to RF energy at 2450 MHz.
W A R N I N G
: Do not attempt to measure
these voltages.
MICROWAVE SYSTEM PARTS
Figures 20 and 21
11. NGC-3062-1 HV Transformer (2 per oven, 1
per kit) - USA, Mexico, Brazil,
S. Korea
NGC-3062-2 HV Transformer (2 per oven, 1
per kit) - Europe, Asia, Pacific,
Australia, UK, Ireland
NGC-3062-3 HV Transformer (2 per oven, 1
per kit) - Japan
12. NGC-3020 High Voltage Capacitor (2 per
oven, 1 per kit) - USA, Mexico,
Brazil, S. Korea
NGC-3020-2 High Voltage Capacitor (2 per
oven, 1 per kit) - Europe, Asia,
Pacific, Australia, UK, Ireland,
Japan 50 Hz
100207 High Voltage Capacitor (2 per
oven, 1 per kit) - Japan 60 Hz
THE MICROWAVE SYSTEM 26