Discrete Tube Phaser

[harry]

Re: Cheating...

Bullshit !  They are cadmium sulfide, or cadmium selenide... and they go
back every bit as far as tubes do. They are NOT cheating in the least.

If Y'all want to be foolish about this... why not just use a spark gap
and a leyden jar !!!  That'd get you back to Ben Franklin or so...

Are we going to go back to the... "I had to dig the copper ore from the
hills with my bare hands"  thread ?

OK then... NO soldering irons either... scopes are OUT ! You can use
an "electrometer" or "galvanometer" if you wish.

H^)  harry  (who usually disses tubes... but would go along here until it gets
TOO silly, eh ???  ;^)

Nils Pipenbrinck wrote:

> Folks, it's really simple:
>
> You can build a tube-VCF with Lowpass, Highpass and Bandpass, right? Add
> together the outputs of low, high and bandpass and make sure the resonance
> is not audible (or build your filter without resonance at all). Then you
> have a voltage controlled phase shifter.
>
> If you cascade a couple of this filters, and connect a simple sine lfo to
> the control voltage you'll end up with a nice flanging effect.
>
> I've tried that in software with a cheap 6dB lhb-filter (3 lines of c-code).
> For a test I programmed two banks of each 3 phase shifters in a row and
> added the signal of the two banks together.. That was a very strong phasing
> effect. It sounded very "digital" because my 3 line of c-code filter suffers
> from aliasing, but it showes, that in theory it should work.
>
> Btw.. Using LDR's is cheating.. I'm not sure, but aren't LDR's made of
> silicium or germanium or another "modern" material?
>
> Nils