SOLVED Madbean Current Lover no signal

jwyles90

Well-known member
Hey all,

I know this isn't a PPCB build but I also know a fair amount of people here have put this one together, so fingers crossed we can get it working. I just finished up this build and am not getting any signal out of it when the pedal is engaged. The LED stays on all the time, and gets brighter when the pedal is engaged, so I'm thinking there might be something going on with the power section of it but am also not sure. I've got it set up to run at 18v with the 3007 chip.

I took it out of the box to make sure there wasn't a ground or short somewhere, and as far as I can tell there isn't since I'm still not getting anything with it unboxed. I'm getting audio signal with an audio probe going in and out of the 3007, and can hear it modulate and do its flanger-y thing when I mess with the rate, manual and feedback knobs, so I'm pretty sure the chip itself isn't to blame either. I went and reflowed a few areas but as far as I can tell the soldering looks good, and when compared to the reference photo in the build docs nothing is jumping out at me as being out of place.

Any suggestions on where else I could look on the pedal to start narrowing down the issue would be greatly appreciated!

The photo size from my phone is too big apparently, so here's a link to the images in a Google folder: https://drive.google.com/drive/folders/1SGt9pc9nhamOFJcnJnCFFCxq1luBbkc2?usp=drive_link
 
Did you calibrate it? The build docs are pretty extensive so test all your voltages against what is listed there, it may point us in the right direction.
Yea I believe it's calibrated as it should be. I can hear it doing all the modulating on the resistors in the modulation section, and then the signal stops once I get to r21. I just tested the voltages and a few of the chips are off, so here are the readings:

IC2 Pin 2 and 6 go back and forth between 10.3-13ish. Tey should be be right around 7v.

IC4 pins 12 and 13 are both around 1.6-2ish when they should be around 6.7v.

IC5 pin 6 is 4-6.8v when it should be 14.8.

Q2 I'm getting swapped readings for the collector and emitter pins. So the Emitter is reading 14.2 and the collector is reading something else (forgot to write it down but it's listed as "varies" in the BOM). I tried flipping Q2 around but that didn't seem to make a difference, still not getting any signal out of it.

I also noticed that the BOM has r20 listed as 470R but on the schem its listed as 100R. I swapped it out to 100R but that also didn't do anything noticeably different.

LED on all the time makes me wonder about your stomp switch maybe?
I thought that as well. I tested the switch for continuity and it beeped as normal when I had it on and off. Might have to try swapping the switch out if it's still going on once I figure out the rest of the pedal though.
 
Agree with Erik S, the LED on all the time is the biggest anomaly. Are you are running it at 18V? How are the voltages on your regulator?
 
So I was curious about c14 and r21 since the modulation signal seemed to stop there. I swapped out c14 and took r21 out entirely. The LED issue somehow was fixed with r21 not in the circuit, but I still wasn't getting any signal from one side of c14. I took that leg out of the PCB and got signal out of it, so I ended up running a wire from that leg to the output of the footswitch and that fixed it.

Not sure what exactly was wrong, maybe there was a broken trace somewhere I wasn't seeing or something like that (seems unlikely though), but in cany case this bad boy is solved and the pedal sounds awesome. Thanks for all your responses!!
 
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