Quote:
Originally Posted by andy
I think you meant to say that the cathodes are where the video signal is applied to the CRT. G1, and G2 should have DC on them.
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oops right thanks Andy.
Tin Can just do the check on the cathodes with the scope for now with the transmitted blank screen, use the horz rate, AC, make sure you can see the entire trace including two horz sync pulses.
after that the G1 and the G2, If you scope works like mine the AC setting should allow you to look at the G2 (using 10x and 5v would be 50v per div) since it should see very little AC at all, assuming the filter caps are ok on those supplies (the 250 and the 870, both derived in the horz circuit). If you want you could start by turning the screen pots fully CCW that would place the G2 at the lowest DC voltage of 250v (but again it should not matter as there should be NO ac anyway).