Re: 7904 problem

Ed Breya
 

From the discussion so far, it seems to me that the +130V supply may be gone. As I recall, there's a small fuse protecting it on the power supply regulator board. If plug-ins are installed and timebase set up for a proper free-running sweep, that should spread the beam out to a workable non-damaging level. If the sweep doesn't happen on-screen even though it should, then the 130V is probably out. In that case, I'd take David's suggestion and unplug the CRT socket or the anode connection to protect the CRT while servicing.

Ed

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