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my first time build, a naughty fish, only makes noise

Started by snaggletooth84, April 26, 2015, 10:59:53 PM

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snaggletooth84

Hi guys
I decided to build a naughty fish but I may be over my head, after a couple months to source the right parts( I dont live in the US) I finally completed it but all I get is noise. I´m using a regulated power supply so I followed the advice on a previous thread and jumpered R25. Both leds turn on but led number two goes off if I flip the range switch to the right. Led number turns on and off if I press the 3dpt (only thing i think i got right really). If I plug in the pedal without my bass plugged to the input there is some constant noise, however, if I plug the bass the noise gets 10 times louder and i get no bass sound, turning the knobs or flipping the switches changes the type of noise a bit but still no sound. I´m uploading some pictures they are from my tablet as right now I cant use my dslr, sorry for the quality. If you guys need voltages and stuff I need to get a mulimeter as mine broke down today.

Any advice is appreciated
Thanks

**edited to remove large pictures, I will post higher quality ones with proper hosting

jubal81

The wiring on the switch looks wonky to me - 4 pins all connected together. I'd check that first.



"If you put all the knobs on your amplifier on 10 you can get a much higher reaction-to-effort ratio with an electric guitar than you can with an acoustic."
- David Fair

snaggletooth84

Hi
It is a bad picture, but i checked and the wire on the middle left pin does not touch the central pin.
thanks

jimilee

Do you have bypass signal? Sounds like a grounding issue, what do you have it grounded to outside the box?
Pedal building is like the opposite of sex.  All the fun stuff happens before you get in the box.

snaggletooth84

Nope, if press the 3pdt switch and led number two goes off I still hear no bass sound, just noise. I don't think I have it grounded to anything really, how should I go about doing that?, also do you think I might have messed up the wires in the input jack? Could it explain the noise? I forgot to take pictures of the jacks, I can post them later today. Being a noob at this I can't even think of ways to troubleshoot it properly.
Thanks for the help

midwayfair

Remove the switch from the equation. You can use just alligator clips; clip the output wire directly to the jack, the input wire directly to the other jack, the ground wire to the sleeve of one jack, and another wire to the sleeve of the other.

There is a troubleshooting rules thread that will give you many steps for proper systematic troubleshooting. There is also an extensive tutorial on DIYSB or a simpler one here.

Micpoc

When you say that you turn the knobs, does that include the trimpot?

snaggletooth84

I´ll have some time to work on it friday. Yes, it does include the trimpot.
Thanks for the help guys

snaggletooth84

Quick question: when i use the aligattor clippers i keep the 3pdt switch soldered to the board?
thanks

march500

Any chance pin 4 of IC4 and C13 are bridged? Could just be how it appears in the photo. Looks like you have electrical tape on the back of the pots--Could a long lead be poking through? I've definitely reversed the connections accidentally on the jacks a few times. Like you said check that.

snaggletooth84

Hey guys
Nope, pin4 of ic4 and C13 were close, but not bridged i made sure that can´t happen now, I checked the back of the pots and the leads are trimmed so they won´t poke through. Today i got me a multimeter and started checking voltages, all the ics have power pin 8 reads 8.93 volts in all of them, i got suspicious of the solder in the pots and switches so i reflowed them, attached the jacks to the metal enclosure and use the alligator clippers to close the circuit. Now the noise is much quieter and if i turn the gain pot all the way up i can hear my bass! (it sounds like a very bad distortion pedal sadly). I checked the voltages in the vactrols and i thought they were odd. The positive side of the led reads 6,62 the negative side reads 5,4 approx. on both, but the resistor side on the one closer to the end of the pcb reads 0,01 on the top and 4,3 on the bottom but the other vactrol reads 0,01 and 0,9. Is that correct? would it help if I posted the voltages for every IC pin? should I get an audio probe?
Thanks for the help

midwayfair

Seriously, read the Madbean tech help rules thread or the one I linked to. Right now it reads like you're just poking around blindly and that will give you systematic steps to debug. If you need help breaking down the schematic for audio probing we can do that but you can't hurt anything by experimenting.

snaggletooth84

So, in the process of complying with the steps in the debug thread (i apologize for not doing it sooner, I was short on time), I have found not one but two resistors with the wrong values, very wrong values. I´ll order correct ones, replace them and update you guys with the results. Thanks for the suggestions.

Coda-effects

The true bypass wiring seems a bit odd to me... Try to check if there is no false contact between the lugs.
http://www.coda-effects.com/2015/03/3pdt-and-true-bypass-wiring.html
To check, use a multimeter in "logic" mod, try any suspect combination of lugs (central left + central lug seems risky to me for instance)

I wrote an article with general guidelines that can be helpful to fix effects (for beginners)
http://www.coda-effects.com/2015/03/debugging-diy-guitar-fx.html