[sdiy] The Visible VCO

[john mahoney]

> Its not really a VCO. Its really just a variable frequency
oscillator.
> The tube is configured as a schmitt trigger. It looks as if the
thing
> would have exponential slopes. One thing that is a bit fuzzy is how
the
> cap gets discharged. I guess thats via grid conduction. Another
thing is
> that it is unbuffered. It looks as if it was a deflection oscillator
for
> a scope or something.
>
> Cheers,
>   René

Maybe I should have written "The Visible Oscillator." I was playing on
the name of the plastic "Visible Man" models.

But... but... doesn't that Frequency Vernier adjust the voltage? It
looks to me like a VCO without a CV input.

What about the Retrace Balancing Signal, maybe that's for high
frequency compensation?

> It looks as if the thing
> would have exponential slopes.

So it's a sawtooth with curved slopes? What's the frequency spectrum
of that? (Magnus!!) I wonder, though, because a linear sweep generator
is a lot more useful.
--
john