[sdiy] New to list and Juno-60 to SN76477

[Scott Stites]

Hi,
As a matter of fact the other night I was going through some chips I'd
bought years ago and found two SN76477's that I'd forgot that I had, and I
sort of looked into it a bit..  As I understand it, the Blacet Dark Star
Chaos module was based on the SN76477.  I don't think Blacet is producing it
anymore and (sigh) I missed the boat on that.  There is a circuit called the
Super Controller by Thomas Henry.  It was featured in his book "Build a
Better Music Synthesizer" and it makes a pretty cool module.  It contains:

*An LFO that can be trigger/delayed, gated or activated by a foot switch
with triangle, square, gate and trigger outputs

*A sweepable noise source with a filter control (internal or external sweep)

*A sample and hold with portamento

I believe the circuit can now be found in his book "Electronic Music
Circuits:  The Reprints"

http://www.midwest-analog.com/cat-book.html

Also, his stuff about the SN76477 may be found in back-issues of Polyphony

http://www.midwest-analog.com/thpubs.html

You might be able to get those from PAIA

www.paia.com

Coincidentally, I just finished hacking a small mini-keyboard into a
row/column matrix and I've breadboarded a digital keyboard design from his
"Build a Better Music Synthesizer" - it works like a charm.  Especially if
you don't have a midi converter, but have a handful of common everyday logic
chips and a DAC0808.  37 keys with a three position octave switch - you can
cover better than five octaves pretty accurately.

A few days ago Cynthia Webster posted this link in answer to another query
about the SN76477, some good information from the Electronic Peasant:

http://www.angelfire.com/electronic/epeasant/circuits/circuits.html

The Blacet Dark Star Chaos can be seen here:

http://www.blacet.com/cool.html

I'd sure be interested in hearing the details of your SN76477 synth.

Take care,
Scott



----- Original Message -----
From: R. D. Davis <rdd at rddavis.org>
To: <synth-diy at dropmix.xs4all.nl>
Sent: Tuesday, September 10, 2002 7:31 PM
Subject: [sdiy] New to list and Juno-60 to SN76477


> Greetings,
>
> It's great to discover a DIY synthesis mailing list!  This is my first
> message to the list, so I just wanted to say "hi" to everyone and
> introduce myself.  For many years, I've been interested in sound and
> music synthesis, going from a simple synthesizer made from a toy organ
> keyboard with home-made switches, op-amps and "top octave synthesizer"
> chips, etc. and a sound synthesizer built using the old TI SN76477
> chip, to playing around with a Juno-60 synth and various op-amp filter
> circuits, etc.  Experimenting with some tube circuits for use with
> music synthesis is another area that I'm looking forward to exploring.
>
> Just for fun, some day I'd like to get around to using my old
> PDP-11/73, PDP-11/44, PDP-8/E and VAX 4000 computers for some
> retro-computer-synth projects.  Several years ago, I began compiling
> data about the historical use of DEC PDP and VAX computers with music
> and sound synthesis, and am fascinated by the work done with DEC
> computers at the old EMS Putney and Great Milton studios.
>
> The other day, I dusted off the old SN76477 based synth. that I built
> over 20 years ago (already?), and thought that it would be fun to do a
> bit of rewiring, replace a few broken switches, add some input and
> output jacks and then try interfacing this to my Juno-60, feeding the
> output of the Juno-60 to the external VCO input of the SN76477, and
> give this a listen while looking at the results on a 'scope. :-) Has
> anyone here tried using the SN76477 this way?
>
> Also, does anyone here know how to use a Teac A-4300 tape deck as a
> 4-track recorder (or if that's truly possible)?  I don't have
> documentation for this tape deck, but seem to recall reading that it
> can be used for this; can I record onto separate tracks with it,
> without erasing what's on the other tracks?
>
> -Robert
>
> --
> Copyright (C) 2002 R. D. Davis The difference between humans & other
animals:
> All Rights Reserved            an unnatural belief that we're above Nature
&
> rdd at rddavis.org  410-744-4900  her other creatures, using dogma to justify
such
> http://www.rddavis.org         beliefs and to justify much human cruelty.
>