I am a little late to the party here, and you probably don't even have the rig anymore, but 1.) Possibly tube... 6BQ5/EL84 final 2.) Most likely, filter caps in a 50+ year rig. If a tube is "lit up" that's just the heaters in them. The power (generally) comes straight off the transformer and usually unless you just flat out BREAK a tube they will most usually light. I like a Teaberry personally and have had several like yours come and go. They sound great. Gotta love a tube pre-amp. My day job is repairing tube guitar and home audio amps, I see it all the time with people who clean out storage lockers who find a cool old piece of kit. Then they get the estimate... lol