Tube Moog (Was:Re: Website update)

[Harry Bissell]

Hi JH...

the original circuit used a UJT oscillator core. Linearity is not real good
over a wide range, but changing the caps would make this go away...

There "were" some really good ($$$) unijunctions at that time, that probably
would have outperformed the one used by an order of magnitude... but alas they
are gone now.  We used to use them in really wide range timer circuits (similar
to your
ramp style divider...)

H^) harry

"jh." wrote:

> > I suppose the limiting factor would be the ratio that the transconductance
> > sweeps over, which I doubt would be enough for the full audio range..
>
> Speaking of limited range, does anybody know why the Moog Modular
> LP VCF had (needed ?) a Range switch to choose between different sets
> of capacitors ?
> Was there a technical reason (such as buffer amplifier's impedance too
> low), or did Moog not fully trust in the abilities (i.e. wide sweep range)
> of his new found circuit, or is there an ergonomical reason to have
> a range switch ?
>
> JH.