[sdiy] analog pitch shifter circuit?

[Scott Stites]

"The same thing can be done using analog Bucket Brigade Devices (Hi, Harry).
You need to modulate the BBD clock with a sawtooth wave.  The upward-rising
(or downward-going for lower pitches) sawtooth wave emulates the effect of
the
rotating tape head, effectively raising the pitch of the BBD output by a
constant amount.  Well, constant until the sawtooth gets to its peak and has
to
retrace back to the bottom again...  "


Yup, and I (and probably others on this list) have such a device, though
it's now in a rather disassembled state (as probably the others owned by
list members are).  Bought it from Radio Shack back in the late 80's (when
you could get cool geeky stuff from the Shack).  It's a cassette recorder
that had two slide pots on it.  One controlled the speed of the tape itself
and the other controlled the pitch of the playback.  It was designed for
recording class notes, etc, and upon playback you could slow down or speed
up the recording while adjusting the pitch so that it didn't sound like a
chipmunk.  Didn't sound like a chipmunk, but did make the recorded voice
sound rather like gargling (though still a tad better than modern answering
machines that have the same feature).  The fun part was you could adjust the
pitch and playback speed for different pitch/cadence transposition effects.
I also used to be able to press down the record/play buttons just so and
have the monitor come out directly when I spoke into the microphone -
sounded groovy low and gargly.  Last time I looked, I believe it had an
MN3004 in it.....

Now if I could only find that old Rat Shack parabolic mirror cigarette
lighter - now *that* was cool......

Cheerio,
Scott