ampage archive

Vintage threads from the first ten years

Tuning calibrating of my valve tester?

 

4/30/2006 3:18 AM

Satamax

Tuning calibrating of my valve tester? Hi everybody!     Well, i've bought a valve tester http://satamax.free.fr/provavalvole.jpg   I would like to understand more about it. How do i calibrate it? What test thoses µA relate to? Isolation, or emission? Both? Could i improve it, to calculate the transconductance and other parameters, beside isolation and emission?     Thanks and best regards.     Max.

 

4/30/2006 5:33 AM

Jack

Hi Max,   Never seen that type of tester before, at a guess I would say it's an emission tester. I'm sure there's others on this forum who will pipe in soon with advice. If it's fairly old, I usually update the caps, check all resistors for drift, burn marks ect, clean all switches and sockets before putting it into service. See if you can download a schematic for it and check all voltages ect.     Jack

 
 

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4/30/2006 8:28 AM
Satamax	Thanks a lot Jack!     Well, it's an emission and shorts tester. There's very few components in there About one diode, one or two resistors, the switches, and the multitap transformer I'll take a picture of the internals later.     Bye.     Max.

 

4/30/2006 1:28 PM
John Culp	If it's an emission and shorts tester, you can't test transconductance. You need a transconductance tester for that.

 

4/30/2006 3:12 PM
Satamax	Thanks a lot John!     Well, what brand of tested could i get cheap enough? I paid this one about 120 zoros, i'm keen on an AVO or a B&K , but realy i don't have the dough for one Therefor i thought i could may be modify or add components onto this one to be able to test and match valves.     Bye.     Max.

 

4/30/2006 5:44 PM
John Culp	I just bought off of eBay for $90 plus shipping an EICO 666. It doesn't exactly measure transconductance, but that's pretty much what its "dynamic conductance" testing actually is.     There's a good section on various tube testers to be found at: http://tone-lizard.com/

 

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