A/B with Tuner AND A/B/Y all in one Schematic: Will this work?

[derwood]

I pulled a bunch of schematics together put this schematic together so that I could have an A/B pedal with a tuner out or switch between tuner and A&B. Many of the desighed used resistors between the 9V + and the LED. Not knowing much about such things I made some assumptions and made this design. Any comments on if it will work weel or if I need better resistor usage?

Here is the schematic:

Here a a few of my references:
http://smallbox.zeonhost.com/projects/abbox/
http://home.comcast.net/~derwood.blues/swbox.jpeg (I cannot recall where I got this so please forgive if it is yours)

Regards,

Darryl

[Mike Burgundy]

Good effort! Some small things though:
For one, the Y won't work. There's always a path to ground then, via either A or B.
While it is a good idea to ground unused inputs, you might be able to get away without it - that makes ABY a lot easier. Use a DPDT, with one switch opting between A and B, and one between their respective LEDs. Use another to couple A and B with one switch, and activate a "Y" LED with the second switch.
I'd also reference the LEDs to ground, and give them their own resistor - which might be a lot higher value, depending on what LED you're using. On top of that, you may want to turn the tuner LED on without turning the A,B (or Y) LEDs off - it's always nice to see where you're going next.
hih

[derwood]

After some thought of the complexity of this and the fact that it did not allow A and B to be in and go to tuner I lowered my expectations and drew this:



The idea was that I hardly ever use a Y but I many times use 2 guitars to one amp or one guitar to two effect sets. I wanted to be able to have a tuner out either way.

Thoughts?...