Sylvania 140 tube tester

[Tubejunke]

I was just wondering if anyone else here has or had owned one of these. They were produced in the late 40s, so we know the limitations. I did find a .pdf file with scroll updates taking me into I believe the early 60s.

This was my first tube tester and I bought it for a song in the early 80s when almost anything tube was junk. It has performed flawlessly ever since. I have seen a lot of testers and have quite a few, but I have never run into another one of these. The dial glass broke years ago, so I have to be very careful with that until I get another piece of glass. Probably just go have one cut.

There is one on Ebay for $89.00, so they are out there. I wasn't looking for one though. More just seeing what other people know about them. The one for sale is listed as a "Dynamic tester" which is I don't know for Dynamic Mutual Conductance. I don't see evidence that this is a D.M.C. tester as there is nothing but the usual controls on it. No micromho, english,or other indication of anything but emissions tests, but who knows. My "state of the art B&K Dynajet 747B has none of that either and is supposedly a D.M.C. tester. The 747B in all it's solid state glory seems to be a good, bad, shorts, and grid leakage tester. Maybe a topic for another thread.

The old testers like that are great for vintage radio, 50s TV, and from what I hear guitar amp tubes can be tested on them. There must be settings for EL-34s out there which I'm sure are just based on a similar vintage tube. I think a lot of amps use 12AX7s as well which have been around forever.