Posts: 1,184
Threads: 49
Joined: Oct 2017
City: Allendale, MI
Russ. I think you are right about the leakage. As I recall, when I tested the tubes that I got from Bob, several showed leakage on my tester even though they were supposed to be NOS tubes. Probably the point is they are new OLD stock tubes!
Posts: 2,118
Threads: 112
Joined: Jun 2010
City: Medford OR (OR what?)
It is likely that one of those is causing the pop on warm-up. You might try shuffling them. On my Panatrope a strong 1st audio is always noisy - or hum. So I just use a good one ~900 gm, no problem
"I just might turn into smoke, but I feel fine"
http://www.russoldradios.com/