3 channel momentary preset selection

[merlinb]

> Don't know why I bother
Memory is bad and I have been distracted by electrical and medical problems.

Not you, I meant the OP.

Fender does it, I had a late 90's Twin with a four button footswitch with LEDs using only a two core cable.

It's cute but it's still old fashioned in that it can only select one of two channels, with a latching footswitch (which is trivial), and you can't use the front panel controls at the same time.

[MetalGuy]

Sure, but read my post.  Once the footswitch is connected these designs won't allow channels to be selected from the amp, only the footswitch.  So you basically have to disable the channel select switches on the amp whenever the footswitch is connected.  No big deal, I guess.  I was just wondering if someone has solved this issue.

The main purpose of a footswitch pedal is to switch amp channels (and not only) from distance (for example when you're on stage), isn't it?? Can you explain why you need to have active channel switches on both sides?

One way to simplify switching is to make one of the channels active when all amp relays are off.

Another way of switching up to 4 channels that comes to mind is the ENGL Z5 footswitch which is well documented.

[PRR]

> Fender does it

And there you go.



The odd rectangle U5 U6 is LM4040 in 10V flavor, essentially a 10V 1% 15mA Zener albeit built out of a lot of transistors. Since we really only must distinguish 2.2 3.3 and 5.5V, 1% accuracy seems generous, but it is still a $0.63 part so it is cheaper than fussing with tolerances and trims. (Does seem like an LED stack would match and track even better....)

Ah... the request was Momentary, not Latching. Oh well.

[merlinb]

Ah... the request was Momentary, not Latching. Oh well.

And for the panel controls to be active at the same time as the footswitch controls, with corresponding LEDs