CM154
XC - SAFETY
- iii -
PRODUCT SAFETY SERVICING GUIDELINES FOR AUDIO-VIDEO PRODUCTS
SHUTDOWN CIRCUIT TEST
Equipment required:
a) K.V. DC meter (0 to 40 KV, high Z).
b) External variable power supply (0V to 8 VDC).
c) Shutdown Circuit.
Apply a voltage signal of an external power supply
through the shutdown circuit (Refer to Figure shown
below). Connect an accurate high voltage meter between
the picture tube anode and chassis ground. Access the
Video Menu and adjust Brightness and Contrast controls
for minimum screen luminance. Wait until the Video Menu
or display disappears. Read the high voltage meter,
ramping up the external power supply from 0 to 8 volts,
until the circuit shutsdown.
SAFETY CIRCUIT TEST PROCEDURE
Equipment required:
a) K.V. DC meter (0 to 30 KV, high Z).
b) Video Generator
Before turning the TV on, connect the HV meter’s nega-
tive probe (-) to ground (DAG ground recommended)
and the positive probe (+) in the anode of the CRT.
Apply a video signal or tune the TV to a crosshatch pat-
tern (either Lion or Convergence). Access the Video Menu
and adjust Brightness and Contrast controls for mini-
mum screen luminance. Wait until the Video Menu or
display disappears. Now, the high voltage meter shows
HV @ 0 beam.
AV SHUTDOWN EXTERNAL
R4
220 Ohm
Q1
121-01187
R3
1 Kohm
RX3704
182K
RX3705
3.57K
External Power
Supply
0 - 8 Volts
R1
100 Kohm
Q2
121-01187
R2
1 Kohm
MODULE
ICX3406
Black
White
White
Black
Black
Red
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