Buffer w/ kill switch

[closetmonster.]

Hey guys,

I am building a basic buffer circuit, and because my tuner has no mute built into it I figured I'd might as well solve that issue. I am just looking for the simplest way to kill the signal coming out of the buffer with a 3pdt switch.

Thank ya's

[GibsonGM]

I would build a SPLITTER/Buffer, and have an "A" and "B" output. When you don't want to use the tuner, you just flip a switch to ground the input!   

Of course, with JFETs, you could always have your tuner plugged in, and you wouldn't notice it being there....

LINK:  http://www.muzique.com/lab/splitter.htm

[closetmonster.]

Thanks a ton man! Just what I am looking for. I will have to play around with that circuit, trying to put this in as small an enclosure as possible.

[GibsonGM]

No problem, AMZ has some great stuff!  I've used lots of his designs in my own rig, including the "A/B + C" there, and have nothing but respect for them.   Why re-invent the wheel, y'know....   

You can fit things like that in a TINY box, the JFETs take up no room...

[closetmonster.]

Should be putting this together later today, the JFETs just came in. I've decided to do a really simple A/B box with a single 3pdt to switch between the two outs. Trying to keep it as simple as possible for my first real build, up until now I've only done basic mods.

I had a question about the schematic you linked to. What exactly is R1 doing in the circuit? Is it just a pull-down resistor?

[GibsonGM]

I believe that is just a pulldown resistor, yes.  The other resistors (R2 & R3) bias the FET. 

[closetmonster.]

Excellent, thank you for all your help Mike. This is all fairly new to me, I grabbed a couple of books on general electronics and audio electronics but I am still just learning as I go.

EDIT: Hah! I just realized that he explains right at the top that it is in fact, a pull-down resistor.

[closetmonster.]

I've been looking around, trying to find an offboard wiring diagram that suits my needs but I am coming up empty. Basically I want to wire a stomp switch in that when engaged, mutes the output to the second buffer and also turns on an LED. Not too sure if I would need a 2pdt or 3pdt to accomplish this.

It seems like it should be simple, but in my state of near-sleep I just can't wrap my head around it.

Thanks again.

[mremic01]

I've been looking around, trying to find an offboard wiring diagram that suits my needs but I am coming up empty. Basically I want to wire a stomp switch in that when engaged, mutes the output to the second buffer and also turns on an LED. Not too sure if I would need a 2pdt or 3pdt to accomplish this.

It seems like it should be simple, but in my state of near-sleep I just can't wrap my head around it.

Thanks again.

This should do what you want. I drew a 3PDT, but didn't use the middle lugs. You can use a DPTP just as easily, and a SPDT if you can live without the LED.
Edit: I just noticed a mistake. The way it's drawn, the OUT2 won't be connected to ground, but it will be disconnected from the jack. To make sure that it's grounded when off, the middle and bottom lugs of the right pole should be connected together directly so that the bottom lug is ALWAYS connected to ground. Or you could just run the top lug of the first pole directly to ground somewhere else, like on a jack's sleeve or on the pcb.