AW: Sequencer idea/quandry

[gstopp at fibermux.com]

     okay I admit it I made up an analog shift register design...
     
     I really tried to cut down on parts so I used a TTL shift register to 
     create staggered clock pulses and LF398 Sample & Hold chips for each 
     register - worked great.
     
     Unfortunately this was one of my protoboard projects which means that 
     I made it work then pulled all of the wires and parts out and threw 
     them back into the parts bin. Someday I think I'll build one up and 
     stick it inside a box so I can actually use it!
     
     - Gene
     gstopp at fibermux.com


______________________________ Reply Separator _________________________________
Subject: AW: Sequencer idea/quandry
Author:  Haible Juergen <Juergen.Haible at nbgm.siemens.de> at ccrelayout
Date:    3/11/97 6:12 AM


> Would it be reasonably feasable to construct a sequencer that was a series 
> of sample-and-holds, so that one could step through the sequence entering 
> notes directly from a keyboard instead of dialing in pots?
     
Serge have a clever unit called Analogue Shift Register. 
Not exactly what you described, but similar.
I have built my own version of such an ASR (no idea how Serge have 
implemented it). My version can be found at
     
http://www.synthfool.com/jhasr.gif
     
Someone (Gene? Joachim?) has built another version with a shift register 
for clock propagation, which is the better solution, IMO.
So just take my circuit as an idea for own experiments.
It's important to propagate the clock from right to left, while the 
voltage
is propagated from left to right, for obvious reasons.
Capacitors will loose some of their charge over time, of course. If you 
want infinite hold times, ADC/LATCH/DAC is the way to go.
For a few minutes holt time, my circuit works fine.
     
JH.