[sdiy] Frequency shifters, again

[jhaible]

Hi Magnus,

thanks for the links - I'll work thru them soon!

JH.



-----Ursprüngliche Nachricht-----
Von: Magnus Danielson <cfmd at swipnet.se>
An: <don at till.com>
Cc: <jhaible at debitel.net>; <synth-diy at dropmix.xs4all.nl>
Gesendet: Samstag, 20. September 2003 14:03
Betreff: Re: [sdiy] Frequency shifters, again


> From: Don Tillman <don at till.com>
> Subject: Re: [sdiy] Frequency shifters, again
> Date: 20 Sep 2003 00:56:53 -0700
>
> > Hey JH,
> >
> > I forgot to speak up before when you first mentioned this topic...
> >
> > I've seen this before.  (!!!)  It was an old issue of the Journal of
> > the Audio Engineering Society, roughly around 1974.
> >
> > It was a voltage controlled filter built with two balanced modulators,
> > a fixed filter between them, and a VCO.  At least two pages long, with
> > a block diagram.
> >
> > Unfortunately that's all my feeble memory can provide.  It probably
> > wouldn't be difficult to hunt this down at a university library.
>
> If you are interested in frequency shifting, I recommend to read Dr.
Gingells
> PhD Thesis. I've put the PDFs at
>
> http://www.takeonetech.de/buchi/magnus/synths/friends/gingell/00index.pdf
> http://www.takeonetech.de/buchi/magnus/synths/friends/gingell/01chptr.pdf
> http://www.takeonetech.de/buchi/magnus/synths/friends/gingell/02chptr.pdf
> http://www.takeonetech.de/buchi/magnus/synths/friends/gingell/03chptr.pdf
> http://www.takeonetech.de/buchi/magnus/synths/friends/gingell/04chptr.pdf
> http://www.takeonetech.de/buchi/magnus/synths/friends/gingell/05chptr.pdf
> http://www.takeonetech.de/buchi/magnus/synths/friends/gingell/06chptr.pdf
> http://www.takeonetech.de/buchi/magnus/synths/friends/gingell/07refs.pdf
> http://www.takeonetech.de/buchi/magnus/synths/friends/gingell/08elipt.pdf
> http://www.takeonetech.de/buchi/magnus/synths/friends/gingell/01chptr.pdf
>
> and you can also peak into these articles:
> http://www.takeonetech.de/buchi/magnus/synths/friends/gingell/1969itt.pdf
> http://www.takeonetech.de/buchi/magnus/synths/friends/gingell/1973itt.pdf
> http://www.takeonetech.de/buchi/magnus/synths/friends/gingell/1975iee.pdf
>
> and the UK patent:
> http://www.takeonetech.de/buchi/magnus/synths/friends/gingell/UK69_1.pdf
>
> In there you will learn quite alot about the frequency shifting techniques
with
> good references. However, the main result here is a much better way of
> designing the filter and I think this is what you should make use of.
>
> I haven't made a webpage with the above links, so I guess this email is
your
> first hint of these files, but please do look at them!
>
> Dr. Gingell is into other stuff these days, but he wants his work to get
spread
> after all these years, and he went over quite some effort to hand it to me
for
> put up on the web!
>
> Maybe you've seen the strange four-phase filter in The Art of Electronics?
> It comes out of this work!
>
> Cheers,
> Magnus
>