No signal RAT build

Started by gertbort, May 03, 2018, 11:23:29 AM

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gertbort

im busy building a proco rat to the original spec, found some lm308's and the right diodes and JFET's. soldered everything according to this schematic from coda effects: https://www.coda-effects.com/2016/01/proco-rat-white-face-1985.html
i checked if there are no dead solder joints (wich there aren't anymore) and checked if everything that's supposed to have 9v actually gets 9v (wich it does).
when i press the bypass switch the LED turns on, but the signal is gone. used an audio probe (1uf cap on the +, ground connected to the rest of the circuit)  to find out where it goes wrong, pressing my finger against the tip of the input jack to hear the buzz.

when the circuit is activated, most of the buzz is gone, directly at the beginning of the circuit already (at the input jack socket) and gone after the first cap (C3).
i checked the cap using a digital multimeter, and it gave the correct capacitance.

i cant find the mistake in the circuit, maybe im missing something important?

if more detailed pictures or descriptions are needed, i will provide ofcourse





PRR

I'm suspecting a mis-wired switch. Connects input to ground, not effect.
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gertbort

checked the switch, that functions normally

rankot

There are few points that are not soldered well, you will find them if you look carefully: solder is not stuck to parts' leads. Take a magnifier if you can't find them with naked eye.

Also, you must have a multimeter, so you can at least check voltages at some important points.
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