Troubleshooting Pedal

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proroby
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Troubleshooting Pedal

Post by proroby »

Hey, so I have a Prescription Electronics Experience old perf board pedal. When I engage the "fuzz" effect it works fine, but when I try to add the octave or swell feature I get a severe volume drop. What could cause this?
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eatyourguitar
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Re: Troubleshooting Pedal

Post by eatyourguitar »

schematic please
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proroby
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Re: Troubleshooting Pedal

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There's a snake in my boots. Someone poisoned the waterhole!
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greeny23
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Re: Troubleshooting Pedal

Post by greeny23 »

for those too lazy...

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proroby
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Re: Troubleshooting Pedal

Post by proroby »

I should also note that this is inside my guitar and is being powered through a TRS cable into a pedal powered by my CIOKS powersupply, I don' think this is the problem because my other fuzz works fine.
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Re: Troubleshooting Pedal

Post by eatyourguitar »

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when octave and swell are both engaged and swell knob is fully ccw you have a 470R shunt on the tip of your output jack. that explains it. the circuit is just made that way. be careful how you have the swell knob set. you could use a dual 100k pot for swell with the other element wired as a volume control that gets louder at ccw. the problem is that you are just attenuating everything if you do that. the makeup gain needed on the output might create more noise than is acceptable.
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