[sdiy] Berfotron/Buchla now triangular, but with 4KHz offset!

[Scott Gravenhorst]

Aaron Lanterman <lanterma at ece.gatech.edu> wrote:

>5) Oh, here's the wild part: we can COMPLETELY DISCONNECT THE EXPO  
>CONVERTER altogether - i.e. disconnect the emitters of the diff pair  
>in the OTA from the collector of the right transistor of the expo  
>converter - and it still happily oscillates in the kHz range! (We  
>discovered this when putting in the 910 ohm resistor mentioned above).
>
>Any ideas? Anyone run into this mystery offset before?

That's interesting and suggests that the oscillator is being fed current, somehow,
without the expo converter - I believe that if you find the source of this current,
you'll also have the source of the "offset".  A misplaced resistor?

-- ScottG

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-- Scott Gravenhorst
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