SOLVED Walrus Julia (PCBGM Julio) help!

Ale_jellybelly

Well-known member
Hi all, I know this is a PCB from a (not even particularly liked) competitor, but I've been lurking this community for some time and I figured it's the right place to try asking. I wanted to order a couple of PPCB kits from Musikding but they were out of stock so I went for the PedalPCB equivalent...
Anyways...
I completed the build and even after trying to adjust the trimpot countless times, I can get a nice sound but with a load of background noise and hiss. Also, I can hear a ticking noise that goes on time with the rate knob, and if I turn the amp volume up, I can hear the noise even with the bypassed effect. So I guess I have to redo all of the wiring even if I was sure I did it all right.
Could it be a problem with the ICs? As I said I got it all from a kit so I am pretty sure the parts are all genuine.
Photos and a video of the background noise:


IMG_20230331_100959.jpg IMG_20230401_154833.jpg
 
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for starters, to any of your transistors wiggle in the sockets? it looks like you soldered the middle legs, which is a good way to keep them in place and still be able to remove them easily. you may want to take them out of the socket and put a bit of solder on each leg to make it a bit bigger. then bend the outside legs a little so they are putting pressure against the sides of the socket when inserted.
 
also -- the photo looks like there might be a stray bit of something on the back side where the green wire connects with the IN spot from the jack. There are a small number of solder points you could also touch up while it is out of the enclosure.

your demo should have an audio signal in use for part of it to get a sense of how loud that background noise is. Even a quiet chorus pedal can have some background digital noise but it will masked by even low level audio input. but there are some iffy memory chips that will work but have a higher level of noise.
 
You go wash your mouth with soap right now. :LOL:
Haha sorry! Should have used "attempt" :D
But send some more PCBs to Musikding, I'm desperately waiting to place a new order! No Chop Shop, no Mach 1 :(
for starters, to any of your transistors wiggle in the sockets? it looks like you soldered the middle legs, which is a good way to keep them in place and still be able to remove them easily. you may want to take them out of the socket and put a bit of solder on each leg to make it a bit bigger. then bend the outside legs a little so they are putting pressure against the sides of the socket when inserted.
No they are quite snug, I just added a bit of solder for safety
also -- the photo looks like there might be a stray bit of something on the back side where the green wire connects with the IN spot from the jack. There are a small number of solder points you could also touch up while it is out of the enclosure.

your demo should have an audio signal in use for part of it to get a sense of how loud that background noise is. Even a quiet chorus pedal can have some background digital noise but it will masked by even low level audio input. but there are some iffy memory chips that will work but have a higher level of noise.
ah yeah, I trimmed that one, the photo was before I did it.
I'll do a new demo
 
Ticking, in some instances, is picked up from the in and out jack wires. To test this without unsoldering anything, pull the jacks out and move them as far away from the PCB as possible. Since everything is still grounded, you shouldn’t have any issues with audio.
 
if you are getting audio with chorusing and all controls are working, it may come down to the "ambient" level of digital noise you are hearing. you may be able to fine tune the trimmer a bit more to keep the chorusing with less background noise, or you may already have it as good as you will get it.
 
Ticking, in some instances, is picked up from the in and out jack wires. To test this without unsoldering anything, pull the jacks out and move them as far away from the PCB as possible. Since everything is still grounded, you shouldn’t have any issues with audio.

I'd move the blue and green wires to the sides of the board before messing with other parts. they're likely picking up all sorts of stray emf from the IC's.
I'll try to move them and see if it's any better
if you are getting audio with chorusing and all controls are working, it may come down to the "ambient" level of digital noise you are hearing. you may be able to fine tune the trimmer a bit more to keep the chorusing with less background noise, or you may already have it as good as you will get it.
I've messed with the trimpot all afternoon yesterday, it's going from mute, to distorted sound, to chorus with loads of noise, no in-between:(
 
I've redone the input and output wiring and it seems it is a little better but when i let the chord ring, the noise becomes very noticeable... not sure what the problem can be, I'll record a demo tomorrow.
Also, now the ticking in bypass has become worse, but it disappears once I put the pedal after the other pedals in my pedalboard! could it be the buffers?
 
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I wanted to reflow some solder joints but I realised my (very cheap) soldering iron is struggling a bit
Ordered a new one, I'll do some work then. I really really like how this one sounds but the hiss is killing me...
 
I built the PPCB version yesterday. Thankfully it's nice and quiet noise-wise. I like the pedal a lot. The chorus effect is more pronounced than my MXR analog chorus, and it's the first pedal I've had that does a pure-vibrato effect (with the blend all the way up). It's the 10th pedal I've built, so I'm no guru on this stuff, but any noise problems I've been able to track down so far with other pedals have all been IC related. Easy troubleshooting step if you've socketed and have extra's on hand. I don't expect you've got a stash of those BBD chips laying around though. I got mine at StompBox parts if you run out of other things to check and want to throw some new chips at it.
 
I built the PPCB version yesterday. Thankfully it's nice and quiet noise-wise. I like the pedal a lot. The chorus effect is more pronounced than my MXR analog chorus, and it's the first pedal I've had that does a pure-vibrato effect (with the blend all the way up). It's the 10th pedal I've built, so I'm no guru on this stuff, but any noise problems I've been able to track down so far with other pedals have all been IC related. Easy troubleshooting step if you've socketed and have extra's on hand. I don't expect you've got a stash of those BBD chips laying around though. I got mine at StompBox parts if you run out of other things to check and want to throw some new chips at it.
thanks for the input, as I said in another post I bought the full kit on Musikding, since I am in Italy it's not easy to get stuff from the US. I'll see if I can find some 3207 and 3102 without breaking the bank. This is only my 4th build :D
 
... (not even particularly liked) (...) since I am in Italy it's not easy to get stuff from the US
There is also a pedalpcb kit available on musikding, same chorus stompbox :


pcb guitar mania has its troubleshooting forum on facebook, I would also post there to get more answers.

Pcb guitar mania is known to rush things and sell flawed pcb, sometime impossible to build without modification requiring a lot of electronic knowledge.
I even suspect they clone other diy brands, when they think they can make money out of it : It's not rare to see a new pcbguitarmania board, shortly after some other diy brand have designed and sold a similar pcb. Obviously, they can't even clone a circuit correctly.
As consequence, diy builders and customers are often doing the prototype testing process themselves, and have to find the necessary mods to get a pcbguitarmania's pcb working.

There is a popular saying on diy forums : "Stay the f%$k away from pcbguitarmania !". From my experience, I tend to agree...

Edit: Looks like you made a mistake in the thread title : "pedalpcb Julio" : surely you meant pcbguitarmania ?
 
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There is also a pedalpcb kit available on musikding, same chorus stompbox :


pcb guitar mania has a troubleshooting forum on facebook, I would also post there to get more answers.

Pcb guitar mania is known to rush things and sell flawed pcb, sometime impossible to build without modification requiring a lot of electronic knowledge.
I even suspect they clone other diy brands, when they think they can make money out of it : It's not rare to see a new pcbguitarmania board, shortly after some other diy brand have designed and sold a new pcb. Obviously, they can't even clone a circuit correctly.
As consequence, diy builders and customers are often doing the prototype testing process themselves, and have to find the necessary mods to get a pcbguitarmania's pcb working.

There is a popular saying on diy forums : "Stay the f%$k away from pcbguitarmania !". From my experience, I tend to agree...
yeah I wanted to order the Caesar but it was out of stock some time ago, at the time I didn't know the difference so went with the PCBMania kit... I posted in the facebook group but didn't have many answers, I'll try again though.
I just noticed that in my kit I have a TL072 instead of the TL022, could it be the reason for the noise? I've read that it has a much higher current draw and it's noisier...

Also I just ordered 3 PPCB kits :)
 
I can hear a ticking noise that goes on time with the rate knob, and if I turn the amp volume up, I can hear the noise even with the bypassed effect.

I have a TL072 instead of the TL022, could it be the reason for the noise?
Did you do the fix described in the build doc, at the bottom of page 7 ? Edit: I see that's ok from your picture.

First, I'd try to disconnect the Rate indicator led, if there is one. The noise might come from it.

You can always add a TL22 in your next order at musikding. Your local electronic shop might have them too. I think TL72 is quieter than TL22, but i can't say for sure, i guess it depends on the application.
 
Did you do the fix described in the build doc, at the bottom of page 7 ? Edit: I see that's ok from your picture.

First, I'd try to disconnect the Rate indicator led, if there is one. The noise might come from it.

You can always add a TL22 in your next order at musikding. Your local electronic shop might have them too. I think TL72 is quieter than TL22, but i can't say for sure, i guess it depends on the application.
Yeah I jumpered those two pads
The ticking goes away when I put the pedal in the chain, it's only there when I play the pedal by itself...
Now the problem is the hiss/background noise when the pedal is on, I can't understand if that's the "normal" noise or not
 
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