SOLVED Triangulum Boost Bleeps

[AlexosTitanum]

Hi everybody,

I recently built a Triangulum Boost a few days ago. I have the problem that there is a high bleep/ whistle sound when the pedal is switched on. It intensifies if i turn up the poti of the pedal. When i play the guitar the noise disappears and comes right back when i stop playing.

Any help is appreciated

Thank you!

Greets Alex

 

[zgrav]

The Triangulum PCB has a charge pump IC, and there are different versions of these ICs that have very similar part numbers. You need to make sure you are using the part with the "S" in the part number (TC1044SCPA"). and if you have the right part, you need to make sure that pin 1 and pin 8 are connected to each other. The charge pump emits a high frequency noise when it is operating, and the part with the "S" in the number is designed to shift that noise out of the audible range when pins 1 and 8 are connected. The schematic for the Triangulum effect is not in the build docs yet, but you can look at another effect with a schematic that uses a charge pump (like the Twin Face) to see how it should be connected.

 

[AlexosTitanum]

Hey,
Thank you
I will try it asap!

 

[AlexosTitanum]

Hey,
I just connected pin 1 to pin 8 like in the picture below, but the problem still occurs. May there is another problem?
Here is a short video of the problem:

Greets Alex

 

[zgrav]

Did you confirm you have the right part for the charge pump? If you don't have the one with the "S" connecting those 2 pins will not do anything. Also, did you check first to see if pins 1 and 8 were already connected? They should have been.

 

[AlexosTitanum]

Yes the charge pump is the same as recomended. I think the pins were already connected but i wanted to be sure.

Greets alex

 

[zgrav]

You could have verified the connection between pins 1 and 8 using your digital multimemter to make sure as well. I suggest bend your transistors upright again when you are troubleshooting the board because it looks like the leads might be touching the resistors when the transistors are bent over. If that makes a difference, you can fix it by repositioning the transistors.

Some of your holes on the board on the side with the parts do not look like they have solder on them -- I would probably touch up those parts to fill in those holes to ensure a good connection with each side of the board since there can be circuit traces on each side that need to connect to the parts.

Another simple thing to check --- Do you have another charge pump IC? If you do, try swapping it out for the one on your board just in case you have a defective charge pump chip (always a good ideal to have a spare for that part). You could also swap out the other IC to check it, even though it is unlikely that it is causing your beeping.

 

[zgrav]

If those things do not help, you may need to wait for the circuit diagram to get posted. That will make it a lot easier to figure out where the problem might be.

 

[Robert]

That sure sounds like it could be charge pump oscillation. A friend recently got a batch of 7660's from Mouser that oscillated in the audio range, despite having the S suffix. Swapping out from another source stopped the issue.

I'll get the schematic posted for this one today.

 

[AlexosTitanum]

Thanks a lot,
i have a new charge pump on its way right now and also i will touch up the solder joints tu make sure i have fine connections.

 

[AlexosTitanum]

hey,
i swapped the charge pump. The pedal works fine now. Thank you very much!

 

[zgrav]

congratulations!