Re: Fulltone 2B - Great Boost with limiter

Posted by fx-fidden on Jan 02, 2021; 5:32pm
URL: http://guitar-fx-layouts.238.s1.nabble.com/Fulltone-2B-Great-Boost-with-limiter-tp49584p49598.html

This is my UNVERIFIED layout.
Edit: but probably it's ok.



I omitted just the millennium bypass, I think that BS250 circuit is a sort of millennium bypass or similar switching system that I believe we could leave out without any problem.

If I get the wiring the input from the jack goes in the input of the circut, when the boost is engaged the whole circuit works and the DPDT footswitch gives the ground to the negative side of the LED.
(For the novice: the positive side of the LED should be connected to the positive lug of the DC jack trhough a resistor between 1k or 4.7k.)
In bypass the footswitch connects two points in the circuit getting simply "booster" setted at unity gain: so it's a buffer.
The original opamp seems unknown, a TL071 or similar should works fine, the difference should be subtle.
The tape of the Gain pot is not specified, I opted for this circuit a log, but a linear will work, too.
Maybe you can compare the pot used it with some demo of the original.

Tell me if there's any mistake on the layout or someone build it.

Edit: I just noticed that I forgot the 1N4005 to the ground in the power supply section. I say that is excessive and not necessary, the 1N5818 (that could be even a 1N5817) will protect the circut enough.
Anyway I moved a bit some parts and I have included it.

Edit 2: I corrected the orientation of the output cap.

And now this is VERIFIED by cjonesplay.