Forum dedicated to helping people debug and troubleshoot non-functional pedals or builds. Please use an clear and informative title, indicating circuit and basic problem. Don't forget to mark the issue as fixed if this is the case.
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Debugging 101 General rules and hints to succesfuly bring back that old pedal to life
I recently got an old V2 EHX Small stone in that didn't work. In the end I traced the problem to a non functioning EH1048 IC in the LFO section. I replaced that IC with a socket.
- With a spare EH1048 I got from another pedal I get a fine working EHX Small Stone
- With a CA3094 I don't get any working sounds
In all the schematics and information online I can find that everybody mentions that the EH1048 is a rebranded CA3094.
Hi All, I got an old Boss BE5 multi-effects cheap from Ebay. It mostly works OK but the compressor wasn't working at all. I took it apart and found that someone had changed out the 1 microfarad electrolytic coupling caps for polyester ones but they clipped the leads of the old caps on the component side and tried to solder the new caps on to the tiny bits of the old legs sticking up. This was a bit of a mess and some of the solder joints had broken. Anyway I cleaned up the solder pads, removed...
Does anyone know where to get a replacement DC jack for this pedal? It is not the typical DC jack, there is an additional switching element - it has 5 pins on it. The only source I found so far is
and that's a little expensive for a dc jack and not too available.
I recently purchased a vintage Shin-Ei FZ-1A fuzz pedal. It works however there is significant back ground static noise while the pedal is engaged. I basically have no experience repairing pedals however I do have a soldering iron and a meter and figured it maybe something simple. Any help would be greatly appreciated!! I am not sure how to post pictures but here is a link to one that is exactly like mine.
Good evening everyone, I know these are pretty basic questions, but since I'd like to start venturing into building some of these effects , I'd like to have the clearest ideas possible.
What I'm asking you is how these three different types of pedals should be used:
Preamp and amp emulation: should they be used like any other pedal or should they be put in the send-return? What should we expect in terms of sound? That is: if I put a Fender amp emulator on a Vox AC30 will it sound like a Fender...
I've been working on a WH-1 recently that didn't function yet seemed to have proper clocks and voltages. I don't have a schematic so I was doing what I could. I had another WH1 come in with separate issues, but the effect functioned after fixing. I took the opportunity to swap some ROMs to see if I could find the issue (I already previously swapped the big IC don't remember the label with no change). Swapping U22 brought the LED back, but no effect, then it seemed to freeze up. Also swapping...
I'm a new member and new to pedal building. Thanks for the forum!
I just completed a build based on the Small Bear Electronics Ursa Minor distortion circuit.
I completed the breadboard build and liked the sound of the two main options a) using a Darlington pair of transistors, and b) asymmetric diodes using an Si b2b with a Ge + Si. In fact, I liked it so much I decided to do a full pedal build.
Shipping costs to Australia made ordering the dedicated PCB and enclosure uneconomical,...
I built the Aion P2 (Cygnus) it sounds very good but it is extremely noisy when the volume and sustain control are high (no hum but white noise hiss).
I have already tried several transistors and double checked the wiring and soldering.
Is it normal for the P2 to be so noisy?
I bought a broken RV-5 because I thought I could repair it. First thing I noticed is that somebody tried to replace the D1 with another non SMD diode, but I quickly replaced it with the original part. By then, I had noticed the IC6 S8520E33 was hot, so I did the 3v3 stabilization mods, except that I used a LD1117V33 with a TO 220 package (I checked and it seems to be the same as the other one; I couldn't find the SOT 223 package anywhere where I live). I soldered the 1117 with little wires...
Hey Folks. New to this site. I repair old amps and occasionally old pedals.
Trying to understand and get this pedal working correctly.
The pedal is working but I notice the following
The red check LED does not light up. I believe it should be ON when the pedal is active. Or, maybe the older versions did not do this?
When running on a battery I see the full battery voltage at the board.
When running on a wall wort there is a 3V drop at the board which I trace back to the PS adapter socket...
If I set the guitar volume to less than 95% the pedal seems to tune in to mains hum. The guitar has no hum when plugged into my Zoom 3000 so why would the Boss pedal give trouble? I bought the Boss off Ebay so I did a factory reset that went fine but setting the pedal sensitivity or range of the toe & heel switches didn't do what the manual said. It appeared to log the two positions with the right led states but pressing the switches a second time was supposed to switch it to normal mode. Is...
I made a vero layout of an Ibanez BP10 bass compressor, based on the schematics of GGG. I checked it several times but could not find an error so far. But my build does not work. I checked the layout again and did the typical soldering troubleshooting, but no success. So I give up and will do some other build. If anybody wants to continue and do some debugging - here it is for free use.
Just wondering if any of you have experienced this weird issue with an Ibanez Tube Screamer? here's what's happening:
* Initially the pedal seems to be working fine when it is in bypassed mode.
* When you stomp on the little foot treadle to un-bypass the pedal there is a weird swell effect where the volume starts off soft and gradually gets louder.
* When you stomp on the little foot treadle to bypass the pedal, there is the same volume swell effect.
I have a Dunlop UV-1 that's giving a really soft effect. The controls all work and you can barely hear the changes. I've replaced q16-q18 and tested caps with no success. The bulb is working, but seems to either be not getting bright enough or dark enough. I'm getting the 15V on it. What should the voltage range be on the other side?
Can anybody tell from the schematic what it should be?
Symptoms are that the LFO is not oscillating, so the right-hand LED is not flashing - it's on solidly.
Here's the schematic for reference:
I'm not seeing the triangle or sine wave forms on the output of op-amp IC-4b, instead I measure 14v DC. I've removed the chip and put a socket in so I can test alternate chips. Even without the chip in place I see 8v on pin 7, dropping to 2.8V when I adjust the vibrato rate control.
Hello there,
Im building a little Vox treble Booster v807 clone. Very simple, no controls.
The pedal is working fine when activated BUT the Bypass signal is non existent - no sound at all, not even when I remove battery.
I have checked the dpdt footswitch wiring and even changed the footswitch all together. When I remove the ground wire from one of the lugs of the footswitch (as per your standard pedal wiring diagrams), I get a bypass sound that is reminiscent of Tone Suck aka complete loss...
I was just going to use my Digitech QM-1552 Digital Multimeter to test the diodes in my Ibanez TS-9 Tube Screamer to see if any of them were faulty, I switched the multimeter to its Diode/Continuity test and then my multimeter let out a beep indicating continuity, I thought that maybe the probes had shorted together so I checked them, everything seemed normal, the probes weren't touching each other, so I tried removing the probes, first the black one, the continuity...
Hi, I've build several Benson Preamps, but today, while assembling a new one on a new PCB, I encountered a problem that I can't diagnose.
With gain set to 50% or more there is some sort of sizzling noise, like high-pitched gating fuzz, heavily pronounced at the end of decaying notes (see video:
I've tested the circuit with two different amps and power supplies, different cables, different guitars, I changed all JFETs two times, even build another one carefully selecting every component. It...
Hi everybody, new to the forum here!
Sorry for my English, I’m Spanish.
I have built a Sola Sound Tone Bender Mk 1 ( I attach the layout I followed and some picks of the circuit) and I need some help with something that is going wrong:
I've been trying a lot of combinations of transistors with Ac128, russians... and I always get the same result:
When I use the pedal with my guitar volume from 0-8 it sounds good (or at least I think so...) but when guitar volume is on 10 it sounds crap,...
I added an input buffer, and I'm going to use it as the first stage in a larger circuit. I attached a partial schematic showing the Squeezer portion - guitar input is to the left (into R1), output into an output buffer (starts at C30, lower right).
Here's my problem: the coupling cap C4 at the output of the 2nd op amp is swinging about -3v on the negative lead. Positive lead is ~4.5v as expected. No...
I have recently found in my collection of pedals, one of them.
The problem is that when I step on the pedal to turn it on, the sound is faded. It sounds like the effect is only kicking in very little. If I keep my foot down on the pedal, the sound Is perfect. I believe something is wrong in the switching circuit. I've tried looking for a schematic but haven't had any luck. Any insight would be helpful.
I'm using a Voodoo Labs ISO 5 power supply...
The pedal works perfectly in 8 second mode. However, when I switch to 2 or 1/2, the effect doesn't work. When it kicks in, it basically doubles the signal overtop of the input, i.e. Just makes the sound a little warmer. There are no trails, echos, or repeats. The delay controls don't seem to change anything. The controls all work perfectly in 8 second mode however. I've recapped and swapped ICs. I get the voltages on the 4066 when sliding the selector switch. Interestingly, if I jump pins 3&4...
W20K is recommended for the tone pot, but I didn't have it in stock, so I made it with B25K.
I know that it is used as a replacement for the W20K in many TS pedals, and I also have a few TS pedals made with the B25K.
However, make my GT-OD with B25K, the tone was too dark when the tone pot was set to 12 o'clock.
I looked for other errors, but there were no special problems, so I purchased a W20K and replaced it.
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