Simple Tube Tester?

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Matt C

Well-known member
Joined
Apr 30, 2012
Messages
235
Location
Saint Paul, MN, USA
I'm aiming to buy a tube tester.  I don't need anything fancy, mainly I just want it to weed out tubes that are totally dead or have shorts that will blow fuses when put in an amp.  If the tester can provide more info that's great, but really I just need a pass/fail type of thing.  Cheap is good.

Should I just grab any cheap old unit (Hickok, etc) I find?  Any specific models that are worth searching out?  Anything I should make sure to avoid? 

Or at this point are those things getting so old and unreliable that I'd be better off getting a modern computer-based tube tester like the uTracer?
 
I have a uTracer, and its great. Just takes some time to build. You can build it really simple with just a tube socket wired up to the main circuit board, or you can build a fancy box with all kinds of tube sockets you plug up to the circuit board.

Or just any cheapie tube tester on ebay should be able to tell you if a tube is good or bad. Just make sure it has a decent size catalog of tube types.
 
bluebird said:
I have a uTracer, and its great. Just takes some time to build. You can build it really simple with just a tube socket wired up to the main circuit board, or you can build a fancy box with all kinds of tube sockets you plug up to the circuit board.

Or just any cheapie tube tester on ebay should be able to tell you if a tube is good or bad. Just make sure it has a decent size catalog of tube types.

+1 for uTracer!
Best,
Bruno2000
 
I have an Eico 667 which will be available for sale once I recap and calibrate it.  PM me if interested.

A great resource for tube tester info is https://tubesound.com/category/tube-testers/
 
peterc said:
Or you could build a tester

http://www.valveheaven.com/2015/03/an-inexpensive-easy-to-build-diy-valvetube-tester/

Peter

That looks really good. I might build one to replace my ancient AVO valve tester.

Cheers

Ian
 
Hey Ian, you should really check out the uTracer:

http://www.dos4ever.com/uTracer3/uTracer3_pag0.html

It would be just as easy as the other one but has a computer interface and curve tracing abilities.
 
bluebird said:
Hey Ian, you should really check out the uTracer:

http://www.dos4ever.com/uTracer3/uTracer3_pag0.html

It would be just as easy as the other one but has a computer interface and curve tracing abilities.
Except it only works with Windows.

Cheers

Ian
 
The Utracer is great and will give you much more information than even a Gm Tester will give you. Definitely worth considering, especially if you also want to match power tubes down the road.

If you just want a go/no-go tester, all of the vintage ones will do the job of telling you how much life is left in the cathode. This is all that the emission testers will do, which is the vast majority of vintage testers out there.

If you also want to get an idea of Gm relative to different tubes, then only a few of the vintage ones will do that in addition to testing for cathode emission. These cost more than emission testers, of course. All the Hickoks (with a couple of exceptions) do Gm, as do models by Triplett, Western Electric (made by Hickok) and Stark (also made by Hickok). In the UK, Taylor and AVO made excellent units that test for Gm.

The thing you want to watch out for with vintage testers is tube settings and socket support. There are plenty of Hickok models that sell for stupid money that came out in the 40s or 50s that you may not be able to find updated charts for.  That means you wouldn’t be able to test tubes that came onto the market a little later, like the 6DJ8, EF86, some of the subminis, nuvistors or compactrons. Even if the tester has the right sockets (not all do) or supports add-on sockets through a plug-in extender (like the Hickok C4or C5), the updated charts for that model may be non-existent or hard to find. Many people find that out too late.

An example is the Hickok 539A. It looks just like the 539C, which sells for idiotic sums. But it’s an earlier model and you can’t use the 539C settings charts with it. There are no updated charts with all the later tubes available for that model. So you end up with a boat anchor that won’t allow you to test all the tubes you may need to test.

Less expensive models that have updated charts (some as late as the early 70s) are the cheaper ones that were used by your average TV repairman. The 600a and 800a come to mind. You can find these for less than $200 a lot of times. 

Just do your homework if you decide to go with a Hickok. You can get burned easily if you don’t.

FWIW, I still use a 750 (one of the FAA models) with the C4 compactron/nuvistor adapter. I have the 1963 settings chart (the most recent available for that model) which has most tubes I want to test, but I still run into less common tubes now and then that I can’t test.  Overall, i’m happy with it, but I still sometimes wish i’d Just gone with the common 600a or 800a.

BT
 
Oh, and one more thing. Don’t buy a Hickok (or really, any tester) from some estate sale vulture on EBay that says “sold as is,  I have no way to test it”. The meters on any old Hickok are very delicate, and depending on the model may be difficult to impossible to replace. Spend the extra on a tested unit from a knowledgeable seller if you want something that works.

BT
 
Thanks for the recommendations. I found a B&K 606 online for a reasonable price so I went for that.  It just arrived in the mail a few minutes ago so I haven't had a chance to test it out, but that TubeSound website talks about it favorably and has some good info about calibrating it.

The uTracer looks great but I emailed the guy about it and he said he does not recommend using it for simple fault testing, so for the moment it's not what I need.
 
ruffrecords said:
Except it only works with Windows.

You’re a Linux guy, right? See here: http://www.dos4ever.com/uTracer3/uTracer3_pag12.html#FAQ13

Also, it looks as if the interface between the test hardware and the computer is RS232, and the protocol is published so it’s just a small matter of programming to write a control application for another operating system.
 
Andy Peters said:
You’re a Linux guy, right? See here: http://www.dos4ever.com/uTracer3/uTracer3_pag12.html#FAQ13

Also, it looks as if the interface between the test hardware and the computer is RS232, and the protocol is published so it’s just a small matter of programming to write a control application for another operating system.

Excellent. Many thanks for that. I will check it out.

Cheers

Ian
 
I have an ex mod Mullard  high speed valve tester with a box of cards , it'll tell you if the tube is in spec or has a short  if you have the right card for the slotted switch mech ,thats about it ,
the results dont give any indication of microphony or how an individual valve will perform in a particular circuit , components are a lot more ruggedised and high spec than the civilian offering ,a new rectifier, regulator valve and voltage reference is probably all thats required get it back to spec. Open to sensible offers if you can find someone to ship this 30 odd kg one armed beast .
Similar to the pic below but with millitary nomenclature, simple to opperate so even a humble foot soldier can be set the task of weeding out duds from a pile .
 

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link to the valve wizards tube tester
http://www.valvewizard.co.uk/valvetester.html

a list of recommended hickok tube testers
http://www.tubewizard.com/recommended_Hickok_testers.htm

Know what you want to test in terms of the tube types and measurements before you buy. You probably won't be testing compactrons  but I would make a list of tubes you need to cover and check it against any vintage style tester you're looking at. Personally, I wouldn't be satisfied if I couldn't test an EF86..

Some of the old testers on eVil bay have damaged tube charts that need to be replaced, keep an eye out for that. You can't operate the tester if you don't have the info on how to configure it. 

All the best,
 
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