Protection Checks
High Voltage Limit Check:
1. Switch TV on, receive Philips test pattern, and set contrast and brightness to their maximum
levels.
2. Connect a resistor in parallel with R715, and ensure that the sound and picture disappear
instantly.
3. Switch TV off remove resistor and wait 10-15 seconds.
4. Switch TV on again to ensure normal operation, then return contrast and brightness to their
previous levels.
Anode/Focus s/c Check:
1. Switch TV on, receive Philips test pattern, and set the contrast and brightness levels to
maximum.
2. Connect a 270R resistor from pin 9 of the flyback transformer to ground.
3. Check that sound and picture disappear instantly.
4. Switch TV off, remove resistor, and wait 10-15 seconds.
5. Switch TV on again to ensure normal operation, then return contrast and brightness to their
previous levels.
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