Simple A/B box.

[Artie]

This is an answer to another thread, but I thought that others might find it valuable. Its just a simple A/B box - not an A/B/Y box. Select one output or the other. It keeps both outputs 100% isolated from each other, and mutes the unused output. It only requires 3 mono jacks, a 3PDT switch, and an enclosure to mount it in.

The top diagram is in schematic form, and the bottom shows the switch terminals. I tried to match the top and bottom colors. I hope this is easy to read and understand. Feel free to ask questions. Beg . . . and I'll buld you one. :laugh2:

 

[Fresh_Start]

Re: Simple A/B box.

Thanks again Artie!

No good deed goes unpunished, though

Two questions:

1) Would you need a 4P/DT switch for an LED light?

2) Someone recently wrote something about putting a 1 meg resistor between the hot & ground terminals of one or more of the jacks to avoid the nasty "pop" some switches produce. I'm probably remembering part of this wrong, but would something along those lines be beneficial in this switch?

Chip

 

[HolyDirt]

Re: Simple A/B box.

Thanks again Artie!

No good deed goes unpunished, though

Two questions:

1) Would you need a 4P/DT switch for an LED light?

2) Someone recently wrote something about putting a 1 meg resistor between the hot & ground terminals of one or more of the jacks to avoid the nasty "pop" some switches produce. I'm probably remembering part of this wrong, but would something along those lines be beneficial in this switch?

Chip

I know I'm no Artie, but I can answer these questions...

1) In order to have the same affect, you do need a 4pdt switch, although, there might be a way around it I'm not seeing.

2) If you place a 1 meg resistor going from the signal to the ground on each OUTPUT jack, it will take away the popping.

 

[Artie]

Re: Simple A/B box.

I know I'm no Artie, but I can answer these questions...

But you're probably better looking. :laugh2:

Those are both correct. My original drawing had the resistors in it. Somehow, they got omitted in the final draft.

One idea I had, that I like better than the LED one, but requires a bit more fabrication, is to use a teeter-totter pedal arrangment. Tap one side to activate the "A" switch, tap the other side to activate the "B" switch. It really wouldn't be that hard to fabricate, and it keeps the pedal passive.

I may build a prototype this weekend to see how it works.

 

[Fresh_Start]

Re: Simple A/B box.

Thanks guys!

Chip