Some readers of this thread may be wondering why there's a capacitor going from the 1M resistor to circuit ground, there's a good reason for it being there which I'll explain, when you close the contacts of the mechanical footswitch, it doesn't just close it makes and breaks contact a few times before it finally closes, this behavior is called "Contact Bounce" in Electronics, it's not so much of a bad in Analog electronic circuitry, but in Digital circuitry it can cause havoc with the normal operation of a Digital circuit, the circuit that alternately turns the two 2SK30A Fets on and off in the TS-808 circuit is a Digital circuit called a Flip-Flop, you will notice that there are also two 1000pF caps connected to the junction of the 1M resistor and the cap going to circuit ground, these two 1000pF caps form the input of the Flip-Flop circuit, the cap going to ground is there to prevent false-triggering of the Flip-Flop circuit by the Contact-Bounce of the mechanical footswitch, if it was removed entirely, the Flip-Flop circuit would be triggered erratically this is because the Flip-Flop circuit interprets the noise-spikes generated by the Contact Bounce as a trigger signal because Digital circuits operate at fast speeds, putting the cap in it's place filters out the noise-spikes and gives the Flip-Flop circuit a clean trigger-signal.
Last edited by DrNomis_44; 27-03-2017 at 10:34 PM.
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