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van der Pol Relaxation and Single Tube Trigger Circuits

2009-04-14 by Lorin Edwin Parker

Looking at some divide by two circuits:

I haven't had much luck prototyping the Pentode van der Pol type circuit nor the single tube pentode trigger circuits - yet. I think the key may be to use a negative supply to bias the suppressor (which I haven't done yet, and isn't always theoretically necessary).

Anyhow I'll scan in some examples. Anybody gotten a good trigger or relaxation oscillator with the van der Pol model? It looks like this was the method of creating sub-octaves on the Hammond Novachord.

Regards,

Lorin E. Parker

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