Author Topic: Cupcake debugging (no sound)  (Read 2076 times)

Matt Gnarly

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Cupcake debugging (no sound)
« on: February 24, 2012, 08:47:32 PM »
Hey folks, I recently built the Cupcake compressor, I wired everything up off board because I'm impatient and it worked fine, then today upon getting a couple enclosures I boxed it up and it worked but it was a rats nest of wiring and upon tweaking the trimpot I subsequently wasn't getting any sound when bypassed or with the effect. I completely rewired it using a 3dpt board, much cleaner and tidier but now I'm still getting no sound when bypassed or with the effect on. The led on the board would no longer light up either after the switch, but the onboard 3dpt LED does. I'm hoping it's something simple, I've traced everything and it seems okay. I've uploaded pics here http://www.flickr.com/photos/mattgnarly/sets/72157629083298746/

Om_Audio

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Re: Cupcake debugging (no sound)
« Reply #1 on: February 24, 2012, 11:39:13 PM »
I had similar issue and it turned out to be a grounding issue. Your jacks are not close to the corners like mine were though. In any event grounding could cause it. I was going to ask if the LED works but looks like you might not have one hooked up as your switch board is not populated with LED or resistor.
Hope you sus it out soon-
C
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alanp

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Re: Cupcake debugging (no sound)
« Reply #2 on: February 25, 2012, 12:20:16 AM »
Have you tried putting an insulator between the back of the pot and the back of the circuit board? Remember, the pot back is made of metal and will short anything it touches. I've got a section of ice cream container in mine separating them.
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Matt Gnarly

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Re: Cupcake debugging (no sound)
« Reply #3 on: February 25, 2012, 12:59:59 PM »
I had similar issue and it turned out to be a grounding issue. Your jacks are not close to the corners like mine were though. In any event grounding could cause it. I was going to ask if the LED works but looks like you might not have one hooked up as your switch board is not populated with LED or resistor.
Hope you sus it out soon-
C

The LED coming from the Cupcake board was not working after I added the 3pdt board, so I wired up the 3pdt LED and it worked.



Have you tried putting an insulator between the back of the pot and the back of the circuit board? Remember, the pot back is made of metal and will short anything it touches. I've got a section of ice cream container in mine separating them.

I used electrical tape over the pot and the bottom plate.

Thanks for the help thus far guys

Matt Gnarly

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Re: Cupcake debugging (no sound)
« Reply #4 on: February 25, 2012, 06:36:31 PM »
Quick update, I tried the pedal again, still no sound when bypassed or when on but when I was messing with the trimmer with the effect on I started getting some hiss which leads me to believe that issue is likely with my input wiring, I'll be rewiring it tomorrow. I'll keep everyone updated as I'm sure it's helpful for others to learn from my mistakes.
Speaking of mistakes, I realized that the drill pattern I used for another pedal is completely unusable so it looks like I'll be using it as a breakout/proto pedal to test out future PCBs.

Matt Gnarly

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Re: Cupcake debugging (no sound)
« Reply #5 on: February 29, 2012, 10:47:15 PM »
Update: Rewired it, checked all the solder joints on the board and now she's up and running. It sounds great, I have it set pretty low as a fairly subtle compression that works great for my music. I'll have to build another compressor at some point for variety, maybe something similar to the Diamond Comp.

Om_Audio

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Re: Cupcake debugging (no sound)
« Reply #6 on: March 01, 2012, 01:52:54 AM »
Congrats man!
C
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Matt Gnarly

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Re: Cupcake debugging (no sound)
« Reply #7 on: March 01, 2012, 04:55:24 PM »
Congrats man!
C

Thanks, I made a lot of rookie mistakes in the process but the end product turned out great. Now I just need to find a better decal method, I tried Letraset matte decal paper but wasn't happy with the results. My brother is a pretty good artist so I think I'll just get him to do the next one up with a paint pen or something.

alanp

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Re: Cupcake debugging (no sound)
« Reply #8 on: March 01, 2012, 10:08:36 PM »
Dymo labelling works for me, the oldfashioned style with raised letters. Very 60's DIY.
"A man is not dead while his name is still spoken."
- Terry Pratchett
My OSHpark shared projects
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