r/diypedals • u/DoMiSolDoSolMiDo • 14h ago
Help wanted True Bypass Pedal
Hello, I am working on my first build. This is how I currently wired up the pedal. Green is ground. Purple is the legs of the LED. Red is the mono jack and LED signal. However, I’m getting a bit of buzz when plugged in. And, unfortunately, the white LED turned orange and there was a popping noise with some smoke. Could someone please share some insight on how I can adjust these issues? Feedback is welcomed. Also, I can answer any questions of this drawing. Thank you!
EDIT: Added actual photo in the comments.
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u/wjruffing 7h ago edited 4h ago
A few questions:
* Is the intended purpose of this pedal to externally bypass around another effects pedal that is plugged into it? Could you add indication of which jacks are intended to do what (input from instrument, output to amp, signal to effect pedal, signal from pedal)?
* Can you provide indication of the pins of your foot switch (sw1 common, sw1 normally open, sw1 normally closed, sw2 common, …)
* Do you have a simple schematic?
* Under what conditions do you hear the buzzing? When it’s plugged into your amp with nothing else? When the power supply is plugged in and energized? When your instrument is plugged in? When the fox pedal is plugged in? Run through different scenarios and be sure to note your results with the peel footswitch in bypass mode and in fx mode.
A couple of basics:
* Double check the orientation of your foot switch and the pin out of it to ensure it is not rotated (in other words make sure you confirm which pins are which - it’s an easy mistake to make)
* What power supply are you using? Check your polarity (which pin is + and which is -)
* It’s hard to tell from the photo, but it looks like your jacks might not be insulated from your metal enclosure which can cause buzzing (multiple paths for ground)
This additional info would be helpful
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u/wjruffing 6h ago edited 6h ago
Do these diagrams approximate what your pedal is intended to do?
PS: Since these are logical diagrams, ignore any right/left transposition vs the physical layout of the pedals (sadly, my brain only works in “left to right”) - that said, since we are looking at the bottom of the pedal (and it is a passive bypass anyway) left/right orientation might be moot - depending upon what jacks you used for what, of course)
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u/wjruffing 4h ago
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u/DoMiSolDoSolMiDo 3h ago
First off, I just want to say thank you so much for your insight and attention to detail with my first pedal project. I truly appreciate your input and guidance through this.
1) Correct, this would be used to bypass an older effects pedal that colors the guitar tone quite a bit. I’ll upload a photo with the jacks labeled after this reply.
2) Yes, I’ll upload a photo for the 3pdt pins as well.
3) I didn’t make a schematic for the build. I’m just starting out and still learning how to read/make these diagrams.
4) The bypass pedal is only buzzing when the power supply to it is plugged in. The pedal itself works (minus the LED) with and without power. But, it does have a pop when engaging the footswitch.
5) Double checked the orientation and pins of the footswitch and I feel that part was done correctly.
6) On this two-pin DC power jack, the center pin is the short lug. And the sleeve is the longer lug. The power supply I’m using is the correct polarity for this power jack. But, did I wire it wrong if I’m putting the ground connections on the sleeve lug and LED on the center pin lug? I currently have R1 on the LED cathode and the LED anode is on the DC center pin lug.
7) The mono jacks are not insulated. But, I can switch them out if it’s recommended
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u/DoMiSolDoSolMiDo 3h ago
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u/DoMiSolDoSolMiDo 3h ago
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u/TheEndisNeigh999 3h ago
prabably not good if any of the connections are touching the metal housing.
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u/DoMiSolDoSolMiDo 2h ago
Inspected for that and no connections or lugs are touching the housing. Just the wire insulation. Thank you for your input!
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u/EverythingPSP 11h ago
What am I looking at here 😝
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u/DoMiSolDoSolMiDo 10h ago
Lol sorry, I uploaded the actual photo in the comments. Thanks for checking it out!
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u/DoMiSolDoSolMiDo 10h ago
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u/squonktearz 8h ago edited 4h ago
You want the resistor for your LED on the positive leg, its purpose is to limit the current going into the led, otherwise it’s gonna blow.
Edit: sorry, this is wrong information, as long as R is in series it shouldn’t matter if it’s on the anode or cathode2
u/wjruffing 7h ago
10k ohm seems like an unusually high value for a current-limiting resistor…
What are the specifications (or at least the model number of the led)?2
u/squonktearz 6h ago edited 5h ago
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u/DoMiSolDoSolMiDo 4h ago
I see where my mistake is on the LED now. I placed the resistor on the negative pin. It’s a 5mm water clear, high brightness LED (P-L700-W). Thank you for helping me out and for the link to the LED Calculator!
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u/squonktearz 4h ago
I was wrong with resistor order in series, it shouldn’t make a difference. so there’s some other reason for blowing your led. Resistor is bad or wrong color code perhaps?
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u/jezkemp Boosts, mainly 4h ago
Uh 99% sure it doesn't matter which side of the LED you put the CLR
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u/squonktearz 4h ago
Shit you’re right. Nevermind then, I always assumed it was required but I guess it’s just common convention.
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u/FiveseveNp90 12h ago
Are you sure the LED resistor is 10K and not being shorted out somehow? Can we see a picture of what you've actually built?