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Cgs synth

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Re: CGS90 Phaser

2018-04-11 by Ken Stone

Check the values of the other resistors, and look for shorts etc. Something is turning on the transistors way harder than they should be.

On Wed, Apr 11, 2018 at 5:29 AM, andrew buscher hansbuscher@... [cgs_synth] <cgs_synth@yahoogroups.com> wrote:

Hello. Recently built this phaser. It works but the 3046 and 220Rs get quite hot. I swapped the 3046 with BC550s in 4 positions and the 123 transistor is boiling.
When manipulating the Phase control I get a +2.2v to +4v swing at pin 8. With only the 3046 and vtl5c3/2s in, the circuit draws 33ma on the +15vdc side. I'd like to know more about this part of the Phaser. I looked around for other "vactrol driver" schemes and found nothing that looks like this one. Very interesting.

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Thanks Ken!
-Hans Buscher
310-776-0143 text

[Non-text portions of this message have been removed]




--
Ken Stone otherunicorn@...
Modular Synth PCBs for sale <http://www.cgs.synth.net/>

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