mutron 3 noise in the background.

[Traverse]

HI guy's.

I have build a mutron 3 for a friend, from this schematic

 It's seem to work well, but I notice some noise or whistling frequency in the background, after each not played.
I'm wondering if it's not from the voltage inverter daughter board. I have read some where that they can bring noise or other problem in the circuit.
 
I will post photos and voltage as soon as I get back the mutron.

Thanks for your advice and help.

[Travis]

if you are using a 7660, make sure it is a 7660S with the S. The version without the S will oscillate at an audible frequency

If you bought the charge pump IC from Tayda, many of us (including myself) have been experienced problems with charge pump ICs from Tayda squealing regardless of the model

[Marbles]

I second that. I have been having problems with squealing as well. Rebuild the whole thing again ( can't remember which circuit). Changed every wiring to shielded wire.

Replaced the daughterboard 3 times. After using the 3rd IC it was gone. Put back the other 2 and had squealing again.

I used the 7660s cpa. So I would definitely swap a bunch of those. Not a fan :D

[Traverse]

Hi everyone ! Thanks for the answers.
I feel less alone with my squealing mutron.

I have sheck my charge pump's IC ans it's à 7660s. It's not from tayda, it's from muskding. I will buy some knew one from an other place tout see if I get better results.

But before that I would like to know if some of you have it working without squealing with this charge pump's layout?
Does the schem figure 14 here (schem) will work better? I'm guessing that by comparing the actual schem tout the one from the neutron here, and it as allready worked well.

[Marbles]

Funny thing happened, coincidentally I finally boxed up my Clone Theory today..

What was lurking in the background? Squeals..


I also order from Musikding, and also Newtone and Banzai. I swapped one in from Banzai and no squealing (a bit of ticking, but thats another story). Now I don't know where the other came from, but it could be musikding.

The writing om the bad one was a bit more vague. The (serial?) number was:

V15284P

No I have no clue if that means anything. The one I put in had L609ADQ.

But if you have that the same serialnumber thing, the solution is probably solved with swapping.

[Traverse]

I check the serial number. They wasn't the same but they were from muskding. I order some knew one from other place. When I replace them, I let you know if it work.

Thank you for your hello ans advice.