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Cgs synth

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Re: rev 1 steiner filter resonance oddity

2010-04-23 by Jason Proctor

> >i noticed that the output cap is 1uf on the board, but 10uf on the
>>schematic (the rev1 pre-2010 schem). probably not relevant to the
>>resonance problem, but otherwise significant?
>
>It's pretty insignificant - it just a coupling capacitor. Either is okay.
>
>The resonance control does affect gain - that is its purpose. It sounds like
>one of your signal paths (the feedback path?) isn't working.

well i'm back trying to sort this out. there really isn't much to go
wrong with the feedback path of this circuit, so i'm wondering --

- if there's a way to wire up the resonance pot wrong?

- if the pinout of the 2N2222 varies with package?

- what the resistance to ground should be at various points - i'm
seeing 3.7k between the wiper of the resonance point and ground.
seems a touch low... the 1k resistor in the path raises this to 4.7k.

i'd like to get this in the rack and mangling stuff -- any help appreciated!

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