I am in the process of restoring a Sony STR-7065, and the last thing on my list is getting the lamp behind one of the needles to work. I know for a fact the lamp is good, however when the lamp is put into place, the filament glows orange, but doesn't fully illuminate. Since I tested the lamp in another socket, and am 100% positive that it works, I just don't know how to diagnose the problem. Any advice would be greatly appreciated.

thanks in advance.

My guess would be that the lamp isn't receiving the power it needs. So, there is probably a bad cap in the line. You'll need a multimeter to test