I just picked up my first early solid state, Cheetah, and I'm having a problem with a couple of insert lamps. At first I thought they were bad bulbs, but that wasn't the issue. When I bypass the lamp holder with a good one they still won't light up. After checking with a multimeter, neither are receiving power. I can trace the wires up to the lamp board, but don't know where to go next. Any suggestions? Many thanks in advance.

I forgot to mention that one of these lights originally did work and then stopped. I'll try replacing the SCRs for those lamps on the driver board and see what happens. I admit that I don't really know what I'm doing with the multimeter, but the other lamps were pulsing when tested and both of these bad lamps were just sitting around 0V.

It turns out it was a bad scr. Replaced and now working great.