CGS48 VCO Problem

surfnsammy · Joined: Mar 23, 2016 Posts: 1 Location: Los Angeles

Hi Everyone!

Having problems with getting my CGS48 calibrated correctly.

I'm running on 12V power (I did switch the 20k resistor for the 14k)

I've wired this according to Zthee's diagram:

http://www.thehumancomparator.net/tmp/instructions.jpg

Got through the first couple steps on the Setup instructions on Ken's page (Zero Trim, Pro SP).

I got to the "WS Trim” section on the setup instructions and its a blob of a waveform that slumps back into the original waveform once I stop adjusting the WS trimmer.

I realize its not supposed to be a perfect sine, but its unadjustable via the trimmer. (Video Below)

https://www.youtube.com/watch?v=z1K-i7seyvc

Sub isn't working at all yet either.

If anyone has had similar problems, or can give me an idea of what to look for, please chime in! I've replaced a lot of the chips, triple checked the wiring and parts etc, still nothing..

CGS48.JPG

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2.39 MB

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saw.JPG

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But on pin 6 of the CA3140 it looks more like its supposed to:

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1.08 MB

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rounded_saw.JPG

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Also, the sawtooth at the out put is rounded at the top, and sharp like its supposed to be at the bottom:

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1.6 MB

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241 Time(s)

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