Cgs synth

Hello. Somehow my last message didn't go through, so I'll try
again. I just finished building a dual analog shift register mounted
in a Stooge panel. An interesting module and a lot of fun, but I
have a few questions.

1. On the Stooge panel, an led for the clock speed (I assume) of
each ASR is provided, but I'm not sure where on the board to hook
these up to, or is additional circuitry needed to drive them?

2. Since I made a dual ASR, that means two boards. Is it ok to
jumper the power from one board to the other through the bus on the
board, so I only have to use 1 power connector? Will the jumpered
module suffer from lack of power for any reason?

3. I've been mainly playing around with just one of the ASRs, though
I did try both of them out to make sure both function. I noticed
that I have to retune the VCOs I'm driving with one ASR when I
switched all the cables over to the other one. Is this normal, or
could it have something to do with the fact that I didn't match all
the resistors on either board? I did use all 1% metal film
resistors, though, which the text notes should be pretty close.

4. Is it a good idea to normalise the clock jacks and the input
jacks between the two ASRs?

Thanks

Kevin

>1. On the Stooge panel, an led for the clock speed (I assume) of
>each ASR is provided, but I'm not sure where on the board to hook
>these up to, or is additional circuitry needed to drive them?

No idea here either! Possibly replace the 1N4148 connected to pin 6 of the
TL071 with a LED, and decrease the 100k pulldown connected to the LED to 1k.
Even better, use an emitter follower or transistor switch connected to pin 1
of the 4024.

>2. Since I made a dual ASR, that means two boards. Is it ok to
>jumper the power from one board to the other through the bus on the
>board, so I only have to use 1 power connector? Will the jumpered
>module suffer from lack of power for any reason?

No problems. Just link the two together

>3. I've been mainly playing around with just one of the ASRs, though
>I did try both of them out to make sure both function. I noticed
>that I have to retune the VCOs I'm driving with one ASR when I
>switched all the cables over to the other one. Is this normal, or
>could it have something to do with the fact that I didn't match all
>the resistors on either board?

Precisely why the resistors need to be matched :)

>I did use all 1% metal film
>resistors, though, which the text notes should be pretty close.

There is a compromise going on in my design. In order to increase the
input/output range of these, I have to compress then expand the operating
voltages. This means the core and output are more sensitive to smaller
variations, leakage etc.

>4. Is it a good idea to normalise the clock jacks and the input
>jacks between the two ASRs?

If you want to save patch cords, yes :)


Ken
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Ken Stone sasami@...
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