[sdiy] A simple 12AX7 vacuum tube tester schematic..

[Roy J. Tellason]

On Tuesday 15 January 2008 13:11, jpdesroc at oricom.ca wrote:
> Hi list,
>
> This request is out of this list topics but I thought I could get some good
> advices from you..
>
> I need a simple schematic for a tester of the popular ECC83/12AX7 vacuum
> tube used in lots of audio/musical amplifier these days. I already have 2
> tube testers but because this type of tube draws very little plate current
> my testers meter's needle doesn't go up very far so readings are not quite
> acurates. 

I don't know what kind of tube testers you have,  but the ones I've used _ALL_ 
have some adjustment that gives the proper meter reading for the tube in 
question.  And in the case of the one I currently own,  this is also the 
case.  If the meter needle doesn't go up very far it seems possible to me 
that there just isn't enough emissions in that tube to make it do so.

-- 
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ablest -- form of life in this section of space,  a critter that can
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