Remotecontrolled AB-box. Help wanted

[vonmag]

Hi

I hope I can get some help for at little project. I need to build an AB-box for changing between two guitarinputs to one output.
However the box will not be operated with a footswitch. Instead I want to use the Ampcontrol out on my programmable multieffect unit. Its a simple control that can be either open or closed (shorted or cut) and can be controlled within each patch.
Oh, and I'd also like to have one or two lightdiodes to indicate, wich input is active.

So can anyone help with a simple diagram? I suppose I need some kind of relay, but I don't know how to design the circuit.

Thx

 

[vonmag]

Update
I put a schematic together, and I think it should do the trick, but I do have a couple of questions. Hope someone can help. But first of all: this is what I would like to do:

The ampcontrol in the GT-10 is programmable which is why I want this solution instead of a standard AB-footswitch.

So this is my circuit. First of all - is a relay like this the right way to route an audio signal? Second, the LEDs are standard 2.2V - what are their operating range and especially what are their max value.
The resistor values are approximate, I plan to use trimpots to dial in the right values.

Thanks

 

[davenn]

hi
welcome to the forums
Happy New Year

A relay would be good
if you use a relay with coil rated ~ 9 - 12V you dont need the resistor (500k as shown)

for standard 5mm LEDs off a 9V supply a resistance of ~ 1k would be enough
( at your shown 1M, they probably wouldnt even glow faintly)

Dave

 

[vonmag]

Super - thanks daven, great advice.I guess I'll go ahead and order the parts then.
My dealer only has this relay in 6 or 12V versions and the 12V need 9 - 9.5V to operate the coil, so I fear a standard 9v battery will run dry to soon.

However 500 K might be over the top, I'll experiment a little with the trimpot to get a suitable value.

 

[davenn]

even running a 6V relay off a 9V supply wont be a problem no resistor needed

Dave

 

[vonmag]

No I suppose you're right. The datasheet says max 9. volts, but I guess it can take the 9.4 from a fresh battery

I don't really know a lot about electronics - especially the theoretic parts. But I can follow a diagram and I do know how to solder though, so thanks a lot for your help.
Happy new year

 

[pwdixon]

You might want to look at a latching relay or even a solid-state circuit to save battery power as I would expect your battery to run out pretty quickly when the relay is powered on for any time.

 

[vonmag]

Hi pwdixon. Thanks, I see your point. Problem is that the switch in my GT-10 is non-latching, it is either on or off when I choose a patch, so I need a circuit, that will detect wether the switch is off or on. Can I do that with a latching relay - and do you have a link for one that would work?

Otherwise I guess I'll go with this design, and check the battery life along the line. If it uses to much, I'll have to use a powersupply

 

[davenn]

if you use a latching relay, you will need a few more components to control it
... to reverse the supply to the relay.... not too much of a big deal

but using the unit the way you have currently considered think about which guitar input is most likely to be used for the longest periods of time and make that the unswitched input ie. no power used

Dave

 

[vonmag]

Hi Dave

Thanks, I'll take it into consideration. I was thinking along the same line.
But I`m curious - could you outline a rough sketch as to how it would work with a latching relay? - its always good to learn something new