DIYstompboxes.com

 ???
So what I'm after is basically a loop selector with a bypass. Three switches - bypass, loop 1 and loop 2. I want to be able to stomp on the channel I want and the others to turn off at the same time.
How??
Heres a pic of what I mean...
http://i43.photobucket.com/albums/e396/halfwayquiet/loopboard.jpg
Cheers
HWQ

http://www.diystompboxes.com/smfforum/index.php?topic=43121.0

This isn't the same as what you want, but it may help you out.

This could also inspire you.

http://www.singlecoil.com/tb-strip/tbstrip.html

Thanks for the imput guys. If anyone else can help out it would be appreciated.
Cheers
HWQ

Well you could try the one here:
http://www.geocities.com/race_driver205/simpleswitcher.jpg (http://www.geocities.com/race_driver205/simpleswitcher.jpg)
But that can be used for up to 4 loops (or more if you build more than one and connect them). If your interested ill explain how you use it.

Alternatively I can quickly sketch a simple circuit for 2 channels, using relays, if you'd prefer.

Hey man, thanks for that. I'm definately interested if it can do what I'm wanting. Yea an explaination would be cool.
HWQ

Quote from: Gilles C on July 02, 2006, 01:51:04 AM
This could also inspire you.

http://www.singlecoil.com/tb-strip/tbstrip.html

OOOOOOOOOOOHHH

"Lossa" buttons    lol ;D

im gunna have to build that one day

QuoteYea an explaination would be cool.

Alright then.

What it does
One of the outputs A to D is made high when its switch is pressed, and the rest are made low. Each loop is connected to one 4066 IC, which switches it in if its input (A B C or D) is high.
The circuit is cascadeable, so you can have anything like 4 or 400 loops if you want. A loop could also just be 1 effect.

How it works
The circuit requires SPDT momentary switches. When a switch starts to be pressed, its input to the 4076 goes high. The other inputs remain low. When the switch has been fully pressed, the enable inputs on the 4076 are made low, allowing the values at the inputs to be stored in the memory. These inputs now appear at the outputs, and can switch 4066 ICs.

RaceDriver205,

Don't want to hi-jack the thread   but.....I am really interested in the CMOS switcher and I have a couple of questions about it......then I'll go away

How much signal can you throw into it (I'm looking at switching multiple preamps into a poweramp)
What is  "COM"    Is it ground (common)?
What is the function of the 555 Chip?

Please have a look at my re-drawn schematic...I have included the 4066 chip.  This is complete yes/no?

http://s6.photobucket.com/albums/y230/Bluetubes/?action=view&current=completeCMOSSwitcher.jpg&refPage=&imgAnch=imgAnch1 (http://s6.photobucket.com/albums/y230/Bluetubes/?action=view&current=completeCMOSSwitcher.jpg&refPage=&imgAnch=imgAnch1)

Thanks........

The job of the 555 is to generate a clock signal, to load the inputs into the memory.
If you want to know the peak input signal through the CMOS switches, you'll have to look at the datasheet. Line level signals will be fine.
If you want more than 4 switching outputs, you can make more copys of the circuit. But you must connect the two circuits GROUND, V+ and  "COM" connections. COM is to make sure that when a switch is pressed on one circuit, the other circuit resets its outputs as well, it is not GROUND.
You would need one 4066 per effect:
(http://www.geocities.com/race_driver205/switch4066.jpg)
They would be wired in series, so consequtive "guitar in"s would come from the previous "to output".
Your way could be done as well, but you would need the guitar input to be buffered, and then sent to all the preamp inputs.
(Aint ExpressPCB great)

Ok, so if I am reading this right......

The guitar signal splits and comes in on Pins 1 and 4. 
The transistor turns the 3-4 switch on and off (opposite to the on and off of pins 1 & 2 and 10 & 11)

I won't be switching effects in and out, I'm only switching the guitar signal from one pre to another....or for that matter one amp to another.  So I would like to get away as easy as possible with this (I'm a big fan of K.I.S.S.   My brain hurts when I think too much  :icon_lol: )  Would there be any more circuity involved (besides the buffer) just to use the switches as I had in my badly drawn schematic?

THanks again....I'm a bit of a noob when it comes to this stuff....well, actually alot of a noob....sorry.

No, I dont think it'd be that complicated. Just send the buffered input to all the preamp inputs, send their ouputs to the switches, and sent all the switch ouputs "out1 to out4" directly to the input of the amp.

Awesome...I think I'll give it a go.  Thanks for the Help RD.....I really appreciate it.   :)

For what it's worth I built this circuit from Mark Hammer's site, and it works.

http://hammer.ampage.org/files/DUALLOOP.png

Gilles

It seems to me that this could be done with only two switches and no components (minus LED's and a couple resistors for the LED's)...

I made a simple 2-channel selector using just a DPDT switch and some wires.  It's quite simple, no LED.  In one switch position the first loop is connected to signal in and signal out, in the other, the second loop is connected.  No LED, but If I had used a 3PDT (which I plan to do) an LED could have easily been added. 
If you took a 3PDT switch, turned it into a loop selector as I just described, and simply took another 3PDT switch (or a DPDT with millenium bypass) to create a bypass around it, it seems you'd have a 2-loop selector with two switches (one to toggle between loop 1 & loop 2, and the other to toggle between bypass and not bypass).  You'd have 2 LED's and the whole thing would be extremely simple.

Anyone see any problems with this??

zpyder

Nope, that design is absolutely fine. Same design used to have two switches in a house that turn on the same bulb.

hmmm... now I'm wondering if one could use a second JFET (possibly at the Drain of the first?) to have a millenium bypass that would light up a different LED in either position, so that you could have, say, a red & green one for the two different loops...?

zpyder