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previous: Rich I have finally sat down and started... -- 8/25/1999 11:00 PM

Re: Univibe clone

8/26/1999 2:19 AM
R.G.	Re: Univibe clone I've built a number of the, and they seem to work fine Read "The Technology of the Univibe" for some improvement suggestions. The biggest things affecting quality in this - and in real univibes, same circuit - are 1) getting enough resistance swing on the LDR's; LDR's vary in characteristics a lot. You need about 4K light to 1M dark - at least! 2) LDR speed. You want the fastest response LDR's you can get consistent with wide range. 3) matching the dry and wet signal level at the output mixer to ensure good cancellation. You may have to mess with subbing resistors to get good cancellation in the notches. 4) LDR matching is a minor consideration, but if you buy enough LDR's you can play with it. 5) getting a full-on to full-off swing on the light bulb.

8/26/1999 2:19 AM

R.G.

Re: Univibe clone

I've built a number of the, and they seem to work fine ;-)

Read "The Technology of the Univibe" for some improvement suggestions.

The biggest things affecting quality in this - and in real univibes, same circuit - are

1) getting enough resistance swing on the LDR's; LDR's vary in characteristics a lot. You need about 4K light to 1M dark - at least!

2) LDR speed. You want the fastest response LDR's you can get consistent with wide range.

3) matching the dry and wet signal level at the output mixer to ensure good cancellation. You may have to mess with subbing resistors to get good cancellation in the notches.

4) LDR matching is a minor consideration, but if you buy enough LDR's you can play with it.

5) getting a full-on to full-off swing on the light bulb.

Replies:

Mark Buckingham R.G. - have you ever tried the ster... -- 8/26/1999 3:45 PM