Quote:
Originally Posted by DaveWM
anyway after seaching in vain for a smoke part (found one resistor that had gotten hot, thought it was it, but it was in the vert circuit and was ok), I decided to try trouble shooting.
same deal as when I 1st got the set, mains B+ ok but no flyback LV.
start checking around the horz circuit and found the horz coupling trans did not have any B+ on the primary. Per the schematic its just connected to the 129v (mains b+). but Its open from the trans to the B+ hmmmm. start tracing the pcb and find a jumper that on the set is not a jumper but a resistor. Now in sams there is no resistor just a jumper, but I guess some smart engineer must have figured some goof would spray carpet cleaner on the pcb and mercifully put a low value low wattage resistor in place of the jumper. since I could not read the value on the charred remains (I missed it in the initial check out because it was so small and mounted vertically), I just put in a 1/8 watt 10 ohm in its place.
after cleaning the pcb with a non conductive spray cleaner and blowing it all dry, I fired (sic) it up and back to working (well but for the vert bars on the ends), again.
that was fun and educational.
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Lucky thing it didn't take out the 2SD867 transistors. They're almost unobtainable.
Did you look into the screen source electrolytics. A lot of times they cause strange looking faults in the raster.