3280 and AD533 availability, EN frequency shifter

[Theo]

We used home made freq shifters at a local radio station I used to work for.
One channel was shifted up something like 25KHz, then L&R where summed and
sent over a wide band telephone line.
Later (and better) versions sent out a modulated signal over the same line.
(yes sounds odd, has to do with the fact that the station was not er..
legal )
We didn't use $30 parts.
Have to see if I can retrieve the schematic somewhere.

Basically it worked like this:
Signal is FM moduladed and than de-modulated with the "wrong" frequentie.
The diff bedween the signals is the freq shift.

Hope this helps,
Cheers Theo

----- Original Message -----
From: Debby and Gene Stopp <squarewave at jps.net>
To: <synth-diy at node12b53.a2000.nl>
Sent: Friday, May 05, 2000 8:46 AM
Subject: Re: 3280 and AD533 availability, EN frequency shifter


> I built the EN frequency shifter about ten years ago. I built it exactly
as
> published, with no deviations either in parts used or in circuitry (a rare
> thing for me). It is truly a fantastic module. It's easy to get very
drastic
> "blow your mind" effects out of it. The multipliers I used were either
533's
> or 633's (or something like that, I don't actually remember) which I
bought
> from Hamilton via phone order and personal visit to their will-call desk.
> They were something like $30 apiece, and the circuit uses four of them.
I'm
> not sure what's available these days. Hopefully somebody can answer that
one
> for you.
>
> But I can talk about the circuit - it shifts all of the harmonics in an
> input signal by the same number of hertz, rather than the same interval
like
> a pitch shifter. This means that an input having harmonics at 440 Hz, 880
> Hz, 1760 Hz, etc., with a shift oscillator frequency of 5 Hz, will produce
> an output of 445 Hz, 885 Hz, 1765 Hz, etc. The resulting harmonics are no
> longer integer ratio relations to each other, producing what can best be
> described as a strange inharmonic sound. Of course small shift amounts
have
> a subtle effect and large shift amounts are more drastic. However, unlike
a
> ring modulator, the original sound is still fairly recognizeable yet
> strangely warped. You can actually get the same effect with an FM radio
with
> analog tuning - I'm not sure what the mechanism at work in this case is (I
> never got familiar with FM radio circuits), but it's definitely the same
> effect. Radio nerds refer to it as single sideband modulation - maybe
> somebody else can explain how a radio does it. The radio I use is an old
> Fisher tube receiver, so I don't know if just any radio can do it. You
have
> to tune slightly off-station with no squelch to get the effect.
>
> The effect is used sometimes in sci-fi movies, usually on speech to get
> alien voices. It's not very common. I think I heard it once very briefly
in
> one of the Star Wars movies. Also an old episode of the Outer Limits from
> the early 60's (the pilot episode, called "The Galaxy Being") features a
> frequency-shifted alien voice quite prominently through the whole show.
The
> EN circuit does this perfectly.
>
> Hey this makes me want to go fire it up again....
>
> - Gene
>
>
> ----- Original Message -----
> From: "Paul R. Higgins" <higg0008 at tc.umn.edu>
> To: <synth-diy at node12b53.a2000.nl>
> Sent: Monday, May 01, 2000 4:55 PM
> Subject: 3280 and AD533 availability, EN frequency shifter
>
>
> > Does anyone know what the current status is on the availibility of the
> 3280 OTA?
> > My Digi-Key catalog claims that they still carry it, but people on the
> list have
> > said otherwise.
> >
> > I was also looking at the frequency shifter in the EN Builder's Guide
and
> I had
> > a couple of questions that I knew the DIYers would have answers to.
> >
> > 1)  The dumb question first: what the heck does a frequency shifter do,
> and what
> > is it useful for?  I know it's not the same as a pitch transposer, but
> that's
> > all I know.
> >
> > 2)  Can you still get the AD533 analog multiplier used in the EN
frequency
> > shifter?  If not, is there a substitution available?
> >
> > Thanks,
> > -PRH
> >
> > _____________________________________________
> > Paul Higgins
> > email: higg0008 at tc.umn.edu
> > University College, University of Minnesota
> > _____________________________________________
> >
> >
>
>