I am in need of some help here. I have built a Benzin VH4 from PCB Guitar Mania. The pedal is passing audio signal however it has no distortion (maybe a light overdrive). I have probed the pedal and it seems that audio is nice and full coming from IC1 (Pin 7) but is being cut before it enters IC2 because it is very weak coming out of IC2 Pin7. I also had a hunch that it could be a bad cap in that gain stage so I have swapped out C6,C7,C8 and C10. Is there something I'm missing??????? This is my 5th build and is driving me insane. Also it hums like crazy any time i touch the GAIN pot........... HELP PLEASE!!!!!!!!
Benzin build has no overdrive
Hi all,
I am in need of some help here. I have built a Benzin VH4 from PCB Guitar Mania. The pedal is passing audio signal however it has no distortion (maybe a light overdrive). I have probed the pedal and it seems that audio is nice and full coming from IC1 (Pin 7) but is being cut before it enters IC2 because it is very weak coming out of IC2 Pin7. I also had a hunch that it could be a bad cap in that gain stage so I have swapped out C6,C7,C8 and C10. Is there something I'm missing??????? This is my 5th build and is driving me insane. Also it hums like crazy any time i touch the GAIN pot........... HELP PLEASE!!!!!!!! https://pcbguitarmania.com/wp-content/u ... g-Docs.pdf
I am in need of some help here. I have built a Benzin VH4 from PCB Guitar Mania. The pedal is passing audio signal however it has no distortion (maybe a light overdrive). I have probed the pedal and it seems that audio is nice and full coming from IC1 (Pin 7) but is being cut before it enters IC2 because it is very weak coming out of IC2 Pin7. I also had a hunch that it could be a bad cap in that gain stage so I have swapped out C6,C7,C8 and C10. Is there something I'm missing??????? This is my 5th build and is driving me insane. Also it hums like crazy any time i touch the GAIN pot........... HELP PLEASE!!!!!!!! https://pcbguitarmania.com/wp-content/u ... g-Docs.pdf
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mauman
- Resistor Ronker
I think I'd resolder the GAIN pot, you shouldn't hear any noise when you touch it. That pot is also in the path between IC1B and IC2A. By the way, here's the correct build doc: https://pcbguitarmania.com/wp-content/u ... g-docs.pdf
After re-soldering the Gain pot there was no change, so i ran my audio probe across it again and found that the signal died right after C6 i installed a jumper between C6 and C7. Then the pedal came to life!!! I may have broken a trace on the PCB when de-soldering the original caps or there could be a fault in the PCB itself. Either way the pedal is now functioning as it is supposed to. Thanks for your input