Tube testers and testing - Some questions

[Lonely Raven]

Well, I couldn't sleep last night so I broke out the Heathkit TT-1 Tube Tester, only to find out it wasn't working! While it would light up, I was getting no joy from the needle.

Opened her up to find a huge scortch mark in the signal circuit which I traced back to a blown 25uF/25v cap. I replaced it with one of my Fender spares, cleaned the contacts on the switch and replaced a scortched wire. All seems well now as far as I can tell (the newbie pats himself on the back).

Anywho, so I went about testing some tubes and I'm wondering...besides testing good/bad, what other data should I be getting or recording? What really can I do with a tube tester, or do I need to invest in some other gear to generate useful data?

I ask because I have this pile of 12AX* pulls, and hand-me-down 6v6 and other odds and ends...and I'm wondering if I could be matching tubes or generating any other useful data about the stock I have as I test them. I mean, besides "GE 12AX7 - GOOD".

Your thoughts?

[Ron Worley]

My Hickok tester measures "transconductance", and other parameters. Supposedly it give a better reading of real remaing tube life, not just "does it fire up"

Many much smarter than me on this board can comment better on what is really needed to get a better reading of the viability of a given tube.

Ron

[Lonely Raven]

I believe that's one of the reasons the Heathkit is considered a sleeper. It does TC as well.

[mhuss]

Pretty much any tester that will measure transconductance is good to use. The simpler ones just test emission (basically "can the cathode emit electrons or not?").

All the brands have older and/or cheaper emission-only testers, so shop by features, not just brand names.

--mark

[Tubetwang]

Calibration is also important on these old units...

I've sent mine to Chris Haedt and he did a superb job!:roll:

Unfortunally, Chris passed away a few years ago...

May he rest in peace...

[Lonely Raven]

Calibration is also important on these old units...

I've sent mine to Chris Haedt and he did a superb job!:roll:

Unfortunally, Chris passed away a few years ago...

May he rest in peace...

Oh, I didn't know that. He was recommended to me back when I first got this tester. But it was testing tubes bang on what other testers were showing them, so I never sent it in. Chris was the first guy I thought of when mine didn't work the other night...though I'm glad I figured it out and it seems to be working now.