Quote:
Originally Posted by Console User
Turn the power On and TV comes on with no picture and sound then goes off with about three times of clicking sound on and off. When it comes on it calls what I call Excites the Picture Tube as you can see the flashes around the edges when it comes on. If you unplug the set and repeat hitting the power button it continues to do the same.
Is this in the eeprom or is there an high issue of high voltage in the transformer?
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First of all, check the ground tab at the horiz output heatsink.
If you have the schematic, check any voltage on the secondary of the flyback with a meter with a min/max feature. If the secondary voltages are high, the HV is too high.
There isn't a parameter for B+ regulation or HV regulation in the eeprom, or at least one that has any effect, but I have seen cases when the horiz oscillator was so far off (high) that it caused excessive HV and shutdown. RCAs of that era did try three times before shutting down.
A new eeprom would come with the horiz freq set below the normal rate, so when a new eeprom is installed, the horiz osc parameter would need to be adjusted upward.
A trick that we used to do when someone got into the serv menu and screwed it up or if the eeprom was corrupted by bad grounds was to add some capacitance across the retrace capacitor right on the horiz output. This would lower the HV to below the shutdown level and cause excessive width. Once the horiz osc was set, the cap was removed and the rest of the eeprom alignment could proceed.
Check the B+ out of the regulator. It should be 140 IIRC. There are two low value, high voltage electros in the power supply that started to bark just as these TVs disappeared from our shops. I seem to recall them 10uf at 200V or so. C4105 pops in my head but I'm not positive.
John