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Fatpants noise

Started by Beargod, May 12, 2017, 01:09:33 AM

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Beargod

Im getting a high pitched whine in my fat pants build from the moment the circuit is powered on. It is present when the effect is bypassed or engaged, though it does get louder when effect is on and the boost pot is turned up.
When i check with an audio probe it is present at the board input and throughout the audio path without much variation in its volume.
Ive tried a hand full of charge pumps  2 different tc1044scpa, 7660cpa, and  7660acpa.
The 7660's both had the noise but a different pitch and slightly less pronounced in one, but i cant remember which.
I put the tc1044scpa back in and took voltage readings:
4.41---9.25
4.68---5.91
0.01---4.43
0.24---0.1
https://goo.gl/photos/MXrV8yyAjD84edB27

https://goo.gl/photos/6Whvvf2AypRzpQhA9

https://goo.gl/photos/FtNmp1U7xm7kvb3KA

https://goo.gl/photos/hm7LnC1Fnbiua6jFA

https://goo.gl/photos/LK8Gof5iSvVSedwm8

https://goo.gl/photos/qQaGemof83cMaLnaA

https://goo.gl/photos/n8YvS69umXPcjraG8

I was wondering if there may be a component besides the pump that could be the culprit, i picked parts up at a local mom and pop electronics store and the zenner is a 5w 15v, that was all they had and i didnt think it would matter as long as the voltage was correct, but its the only part i havent used before from up there ive never had problems with any parts ive gotten there in the past. Just spitballing.
Any help is much appreciated.

madbean

FP Jr specs LT1054 for the charge pump. If you are using one of the ones you mentioned you will need to jumper pins 1 and 8 of the charge pump to put the internal oscillator out of the audio frequency.

Beargod

Shoot... I totally spaced on that. I didnt even read the whole part number in the build docs when i was putting it together. Gotta stop drinking and building. Ill jumper it up thanks madbean.