Schematic analysis, trying to understand a guitar pedal circuit.

Thread Starter


Joined Oct 24, 2011
Hey everyone,
I'm trying to understand a guitar pedal circuit.

Schermata 2022-11-20 alle 19.38.57.png

Can someone suggest how this part of circuit works?

I Guess it's for switching (when npn's are on the let current pass, for example for led in this screenshot) ?

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Joined Jan 27, 2019
Q1 and Q2 are connected in a bistable multivibrator circuit. This is also called a flip-flop. Each time the button is pressed it puts the flip-flop into one of two stable states. In this case it is used to provide power to the effect circuit. It is like a latching relay. It doesn’t have to have a reset, it can use one input, so “push on, push off”.

This page has more explanation.