Sunday, June 03, 2007

Free Tube Testing

Down in my basement, next to the furnace, is this RCA store type tube checker that was used to test for shorts, emission and basic tube faults, and also store new tubes for sale. Bob McTeague, "tube man" sold this to me at the MIT flea market years ago, and it is excellent. At that time I realized that this tube checker was technically inferior to my Weston transconductance tester which measures "real" tube performance, but I use this one more frequently, simply because it is handy and always ready to go.

Most of the time it just gets used to ID a bad guitar amp tube, or sort through piles of used Telefunkens and Mullards I pick up at hamfests. Some of them are usually fine. Then both new and used go below as follows:

Shelf 1: 6L6, 6550, 6V6, 5881, 7027A, 6F6, 5AR4, 5U4 etc.
Shelf 2: 12AX7, 12AT7, 6AU6, 6AL5, 6GW8, and so forth
Shelf 3: 1L6, 6CW4, 6DS4, 13DS4,VF14, and a lot of other minis and Rx tubes
Shelf 4: 8930, 4CX250B, 2C39, 805, 807, 810, 4CX1000, 4CX1500B and more tetrodes.

1 comment:

mujtaba hussain said...

amazing! cheers!