• WARNING: Tube/Valve amplifiers use potentially LETHAL HIGH VOLTAGES.
    Building, troubleshooting and testing of these amplifiers should only be
    performed by someone who is thoroughly familiar with
    the safety precautions around high voltages.

different measurements

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Disabled Account
Joined 2004
I have build this input stage for my 6L6GC amp (without the antiringing network).
But with different B+ at the phase splitter.
My measurements (hand writing letters) are a little bit different than the schem's.
Do I have problem with these measurements?
 

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Disabled Account
Joined 2004
C1 may be leaky or you might have a slightly sour 6CG7.
I use 6SN7.Sorry that I didn't mention.It's the same,though.
And it's a new EHX.I have done measurements with other 6SN7s with the same results.
C1 is a new Audyn MKP cap.So,....
edit: DUH! Or your meter is loading that grid down a bit. That's most likely. Your voltages are fine.
Very interesting! :confused: Why not the other grid,too?
 
The impedance. The lower grid in the diagram is fed through a 1M resistor. The meter's impedance provides a voltage divider to ground. For the upper grid, the meter forms a voltage divider with only 47K ohms (or so), so it doesn't much perturb that voltage reading. Your meter would appear to have about a 10M impedance.

BTW, to confirm that I was an idiot, connect the meter from grid to grid (i.e., across the 1M resistor)- I bet it reads close to zero volts.
 
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