Valve Tester

If they glow, this is the place to be
little eddy
Old Hand
Posts: 693
Joined: Sun Nov 09, 2008 2:06 pm
Location: Manchester

#1 Valve Tester

Unread post by little eddy »

Has anyone made one that could be used to measure/calculate gm and Ia?

What about the attached? https://www.valveheaven.com/wp-content/ ... tester.pdf
TD-125/RB250/MC25FL & 'Snail' phono, NAS/SBT with CS4398 DAC, 41MP pre & MoFo Power, still messing with OBs.
RhythMick
Old Hand
Posts: 761
Joined: Fri Jun 23, 2017 12:24 pm

#2 Re: Valve Tester

Unread post by RhythMick »

I have a uTracer kit which I will build after I've completed the amps I'm on with
little eddy
Old Hand
Posts: 693
Joined: Sun Nov 09, 2008 2:06 pm
Location: Manchester

#3 Re: Valve Tester

Unread post by little eddy »

Am I right in assuming you test the valve with 2 different bias conditions and then calculate gm by (Ia1-Ia2)/(Vg1-Vg2)?
TD-125/RB250/MC25FL & 'Snail' phono, NAS/SBT with CS4398 DAC, 41MP pre & MoFo Power, still messing with OBs.
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