Hot Rod Deluxe and Loop-Master channel switching

[mjlee]

I have a Fender Hot Rod Deluxe, which has 3 channels: Clean, Drive, and More Drive. It has a footswitch with 2 switches: the first selects Clean/Drive, the 2nd Drive/More Drive. It does this using a standard 1/4" mono guitar cable. I'm not too technical, but I've seen the mechansim described as:

"All of the modern fender amps that I have ever played with, including the deluxe, use an AC signal of about 18V for channel switching that is partially rectified or reduced by diode drops introduced by the footswitch. These changes in the AC signal are detected buy the amp which allow channel changes to be made. NOTE: this AC signal and it's ground that goes to the pedal is very noisy and should be kept away from audio signals."

I'm considering buying a separate device from Loop-Master which would replace my standard Fender footswitch. Unfortunately, the footswitch on the loop-master is a 1/4" mono latching (not TRS) which does not work with the Hot Rod.

Anyone know a way to make the Loop-Master work with the Hot Rod? Maybe a custom cable? Or a mod to the amp?

[Enzo]

I don;t personally know the Loop Master, but have you contacted them to ask about compatibilty with the Fender and and suggested interfacing?

There is no way to simply convert plain old switch closures to the Fender circuit short of building a small circuit to emutale the FS itself.

[mjlee]

Thanks for the reply. I contacted the manufacturer (loop-master.com), and they simply said it's not compatible and were of no further help.

I know nearly nothing about electronics, so I have to ask the silly question: what would it take to build the circuit emulation you spoke of?

For what it's worth, I did find a schematic for a cable which makes the FS on a G System box from TC Electronics compatible with the Hot Rod. That box has a stereo output though:

Fender Cable Diagram

[Enzo]

What comes to my mind is to simply use an existing Fender footswitch board and wire the interface from your controller to where the stomp switches wound be. Othotherwise, the electrical circuit of their footswitch is not complex, some diodes, LEDs and zeners. Not hard to make up that circuit on a small board and connect your thing to it.