Peavey Classic 30 Footswitch Help

[rmfroyd]

My friend told me his is getting a Classic 30 for Christmas, so I decided to surprise him with a footswitch.  Got it all built up and I am having a few problems.  My main problem being that the closest classic 30 to test with is 20 minutes away at a local Sam Ash.  I have already been there twice today, and I am still not having any luck.

Here is a pic:



I have been using this schematic(I found it on the internet, so it has to be right.....)


From Left to Right:  Reverb, Boost, Channel.

Problems.

Reverb switching works, but LED lights when off, and turns off when on.

Middle Lug to sleeve, top lug to 100k resistor to positive side of LED. Negative side of LED to tip

Boost switching works perfectly, not problem there

Middle lug to sleeve, top lug to 100k resistor to positive side of LED.  Negative side of LED to Tip on Stereo Jack

Channel switch works not at all.  Led works fine, but channels don't switch

Middle lug to sleeve, to lug to 100k resistor to positive side of LED.  Negative side of LED to Ring on Stereo Jack.

Any help would be greatly appreciated, and yes, I am using a stereo cable.

Thanks for looking.

[Stomptown]

During testing, are you positive you are plugging the stereo cable into the correct jack accounting for it being on the opposite side when flipping the enclosure over?

[alanp]

Also, with the resistor on the single jack-stomp setup, I'd insulate that leg or do something to ensure it doesn't touch the switches middle pin, if I were you. It looks like it's touching, but even if it isn't, that's sailing closer to the wind than I'd like.

[rmfroyd]

During testing, are you positive you are plugging the stereo cable into the correct jack accounting for it being on the opposite side when flipping the enclosure over?

I was out and about when reading this and thought 'yep, that is exactly what my knuckleheaded self would do'.  Got home and checked and since I was so frustrated I had left the cables in the switch when I left the store and they were in the proper spots.

[rmfroyd]

Also, with the resistor on the single jack-stomp setup, I'd insulate that leg or do something to ensure it doesn't touch the switches middle pin, if I were you. It looks like it's touching, but even if it isn't, that's sailing closer to the wind than I'd like.

Will do.  Its not touching as of now, but I will fix it.   Thanks

[rmfroyd]

Could the 100k be too much, giving too much voltage drop for the channel switch relay?   Whats the worst that can happen? I blow an LED.  Should I try like a 500R?

[matmosphere]

I think Alan hit it on the nose. I'd check that before you make any changes.

[gtr2]

Make sure none of your jacks are switching jacks.

[rmfroyd]

From the research I have done, the LED's DO NOT NEED resistors since the voltage is controlled by the amps circuit.  Putting the resistors in the circuit doesn't allow the relay to trip inside the amp, hence no channel switch.

This still doesn't not explain the backwards LED on the reverb though.

[rmfroyd]

I removed the CLRs and everything works as it should, EXCEPT that the Reverb LED is out of sync still.

The jack for the channel/boost is negative supply so the LEDs positives are wired to ground.  Could it be that the reverb jack is not negative supply and I would need to wire the LED negative to ground?

Thanks

[mjg]

If the reverb switching works, but the LED is showing the wrong state, I don't think it's your wiring causing the issue.  Sounds like the relay is set up at the other end to send voltage when the effect is off. 

You could get around that by using a transistor to make a 'not' gate, and hook the LED up to that.  That would reverse the state of the LED anyway. 

[rmfroyd]

If the reverb switching works, but the LED is showing the wrong state, I don't think it's your wiring causing the issue.  Sounds like the relay is set up at the other end to send voltage when the effect is off. 

You could get around that by using a transistor to make a 'not' gate, and hook the LED up to that.  That would reverse the state of the LED anyway.

That is exactly what is happening!  I asked some people on the peavey forum.  The reverb is turning a gate on and off in a jfet. Reverb is in when the footswitch pin is grounded.

You think the transistor idea would work still?

[mjg]

My approach would be to breadboard it and see what happens.  But that may be a bit difficult, as you have to try it out in a shop somewhere? 

I think it would work, for what that's worth. :-)   If the LED is working at the moment, just at the wrong time, a 'not' gate should do the trick.  Although you may have to supply power to the LED from somewhere else if the relay is cutting the power to the footswitch when you want it on...? Which would mean a battery in your box just to power the LED maybe? 

[rmfroyd]

My approach would be to breadboard it and see what happens.  But that may be a bit difficult, as you have to try it out in a shop somewhere? 

I think it would work, for what that's worth. :-)   If the LED is working at the moment, just at the wrong time, a 'not' gate should do the trick.  Although you may have to supply power to the LED from somewhere else if the relay is cutting the power to the footswitch when you want it on...? Which would mean a battery in your box just to power the LED maybe?

Yeah, that is what I was afraid of.  If that's the case than I may as well just throw a battery in there and use another lug of the 3PDT.  Unfortunately I have no room for a battery.  Oh well. he gets what he gets and he won't be upset!

[alanp]

Label it as uneffected, or something