[Radioroslyn]

While your under the hood take a look at the 42 sockets. What you are looking for are burnt marks or carbon traces between pins 1 and 2. Pin 1 is at ground potential and 2 is at +300vdc and the ac signal. This can cause these high voltages to arc and damage the socket or the output transformer in extreme cases. When it arcs it will develop a carbon trace which acts like a low value resistor or short. That causes the hv to be shorted the ground through opt. The other side of the heater pin 6 is 6v above ground and pin 5 is at -20 something. Not to much of a chance of a problem.

I have this problem with one of my sets I think it was the 660L. Out of a dozen that I've serviced I've seen it once so it's not a common issue. But opt on the H-13 are. That's been about a 50/50.