Sanyo EM-X471BS, Service Manual Supplement

Page: 4 / 13

CAUTION
- DISCONNECT THE POWER SUPPLY CORD FROM
THE WALL OUTLET WHENEVER REMOVING THE
CABINET FROM THE UNIT. PROCEED WITH THE
TESTS ONLY AFTER DISCHARGING THE HIGH
VOLTAGE CAPACITOR AND REMOVING THE LEAD
WIRES FROM THE PRIMARY WINDING OF THE
HIGH VOLTAGE TRANSFORMER. (SEE FIGURE 2)
A. TEST PROCEDURES
COMPONENT CHECKOUT PROCEDURE RESULT
1) Check for resistance : Across the filament Normal reading :
t e r m i n a l s o f t h e M a g n e t r o n w i t h a n Less than 1 Ohm.
Ohm-Meter on R x 1 scale.
2) Check for resistance : Between each filament Normal reading :
terminal of the Magnetron and the chassis Infinite Ohms.
ground with an Ohm-Meter on highest scale.
1) Measure the resistance : Normal readings :
With an Ohm-Meter on R x 1 scale.
a. Primary winding : Approximately 1.53 Ohms.
b. Filament winding : Less than 1 Ohm.
c. Secondary winding : Approximately 97.2 Ohms.
2) Measure the resistance : Normal readings :
With an Ohm-Meter on highest scale.
a. Primary winding to ground : Infinite Ohms.
b. Filament winding to ground : Infinite Ohms.
Note : Remove varnish of
measured point.
Filament Windings
Primary
Windings
4. TEST PROCEDURES
Secondary
Windings
Figure 2
Figure 3
Figure 4
Figure 5
Ohm-Meter
Ohm-Meter
Ohm-Meter
- 3 -
HIGH-VOLTAGE
TRANSFORMER
MAGNETRON