Members jworkman Posted November 27, 2006 Members Share Posted November 27, 2006 I took apart my crybaby tonight because I wanted to switch a few things around after modding it a while back. I did the true bypass, gain resistor, vocal resistor, low range cap, and mid boost resistor mods found at this page , and also removed the buffer circuit last time. This time I wanted to replace the gain resistor with the original value, and switch to a different model of cap for the low range. When I went to test it out tonight, it was dead! Signal passed through when the effect was turned off, but not when on. I tried a good battery, made sure that it was powered, but with no luck. I'm a beginner at electronics - any advice? What should I check first? Help!! Link to comment Share on other sites More sharing options...
Members JDandCoke Posted November 27, 2006 Members Share Posted November 27, 2006 may sound really really stoopid... but did you plug in the right way? i found that i get the same effect if i plug in some pedals the wrong way round... Link to comment Share on other sites More sharing options...
Members jworkman Posted November 27, 2006 Author Members Share Posted November 27, 2006 Yeah, I'm sure about that. I'm thinking that something might have shorted out? If any of you veteran effect builders have any ideas - how do you usually go about troubleshooting? Link to comment Share on other sites More sharing options...
Members Ampegocaster Posted November 27, 2006 Members Share Posted November 27, 2006 A little late for this advice, but when you're starting out at modding check the pedal (or amp, guitar, whatever) to ensure it works after every mod. This way if it stops working during the modding process you can always step backwards or resolve the problem as you know what caused it to stop working... But on to some troubleshooting...some of the mods you mentioned seem to be replacing on component value with another. Check to ensure your soldering of the new components back into place is good and that none of the traces on the board have lifted (this is sometimes caused when you expose too much heat to the traces) You say you removed the buffer, this was during a previous mod, yes? In which case it should be alright. But did you cut any traces in the board during the current mod? I'd be suspect of the new switch. Get a multimeter and make sure the points that are suppose to be connected when the effect is ON are connected, that is make sure the wire from the input jack goes to the input of the circuit and the output of the circuit goes to the output jack. You might have a ground point connected to the output jack when the circuit is ON. Ensure that power is getting to the circuit and is not being shorted at any point. If the battery gets warm when you insert it into the circuit you have a short. Link to comment Share on other sites More sharing options...
Members jworkman Posted November 27, 2006 Author Members Share Posted November 27, 2006 I should probably clarify ... the pedal worked fine after the first mod. All I did this time was swapping out the resistor and capacitor. The capacitor did take a while to solder, so your observation on the lifted trace may be true. Link to comment Share on other sites More sharing options...
Members Ampegocaster Posted November 27, 2006 Members Share Posted November 27, 2006 Originally posted by jworkman I should probably clarify ... the pedal worked fine after the first mod. All I did this time was swapping out the resistor and capacitor. The capacitor did take a while to solder, so your observation on the lifted trace may be true. Ok, I misinterpeted what you did during this mod, but if it was just the resistor/cap swapping then it could very well be a lifted trace. Take a visual inspection of each of the points you soldered and observe any damage. If not then use a multimeter from each of those points to a common point in the circuit and see if the connection is broken. That is, follow where the traces go from the freshly soldered points to "stock" solder points they are connected to and check for continuity. If it's a trace that's lifted you can either use excess solder at the point to secure the floating trace to the component. Otherwise you can use some wire to connect the swapped component leads to the point found by following the traces on the board. Hopefully my descriptions arn't to cryptic. Link to comment Share on other sites More sharing options...
Members jworkman Posted December 1, 2006 Author Members Share Posted December 1, 2006 I've tried desoldering and resoldering the parts and even the switch that I put in, with no luck. If I plug the cords into the wrong jacks, it does let some sound through when engaged, but it's kind of a backward volume pedal rather than a wah. I've tried testing for voltage between the ground wire and about every connection on the board. I'm stumped. Any advice how I should go about troubleshooting this? How much would I have to pay someone to figure it out for me if I don't prove to be capable? Link to comment Share on other sites More sharing options...
Members jworkman Posted December 1, 2006 Author Members Share Posted December 1, 2006 Here's how the switch is wired up. It seems like the effect input is grounded when it is switched on as well as off. I don't understand, because it worked last time I wired it up! Link to comment Share on other sites More sharing options...
Members andreas Posted December 1, 2006 Members Share Posted December 1, 2006 If the resistor and capacitor are the only things you changed this time around, the problem should be fairly easy to spot. I'd carefully desolder both, cleaning up with desoldering braid, and take a long, hard look at the soldering pads and traces. If they look ok, I'd put in fresh components and carefully solder them in place. It *should* now work as intended. But... chances are that something else got moved/damaged while you did the mod. A bad solder joint elsewhere might have come loose, for instance. If you can take a few pics of the board (both sides), wiring and switch, e-mail them to me on andreas[at]stinkfoot.se and I'll have a look to see if I can spot anything obvious. /Andreas Link to comment Share on other sites More sharing options...
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