My tester that does a pretty good job with transconductance, etc. is acting a bit funky. I honestly haven't used it for about 5 years and it appears that something went awry while it sat around. Dr. Sol might be able to assist... but honestly, it might be easier to see if someone else has a working unit.
I've got a bunch of rectifier tubes and preamp tubes that I'd like to test to see if they are any good.
I've got a bunch of 5U4G rectifiers and a box of 5R4 rectifiers.
I've also got a ton of 6SN7 tubes here that I'm not sure if they are any good or not.
Any help is greatly appreciated... Thanks!