Mark IV external switching jacks current and voltage

[aaronlyon]

I'm thinking of building a MIDI switcher for my Mark IV:

MIDI out -> Arduino microcontroller -> Mark IV external switching jacks

This will allow me to use my MIDI foot controller to simultaneously change patches on my Line 6 X3 and Mark IV at the same time, using a single pedal board.

My MIDI pedalboard is the Behringer FCB1010, which has two 1/4" switching jacks, but the Mark IV needs six. I already have an Arduino and some experience programming it.

I need to know what voltage and current flows across the Mark IV's switching jacks when closed, so I can build the appropriate relays for the Arduino.

 

[zebpedersen]

Bump - this sounds interesting. I've built some interesting digital FX with Max/MSP going into the front and into the loop of the IV, but switching the whole thing simultaneously (including FX & channels) over MIDI using an Arduino and a MIDI board would be awesome.

 

[aaronlyon]

I sent Mesa this question on Aug 16. No answer from them, either!

 

[ryjan]

I don't think there is any current running through the switching jacks. When you short the tip to the ring it closes an internal relay in the Mark IV.

 

[aaronlyon]

I don't think there is any current running through the switching jacks. When you short the tip to the ring it closes an internal relay in the Mark IV.

I don't think there's any significant current, but there is some. If you connect two wires and no current flows, there's no point in closing the circuit! The point is, if the current is under 20ma, you can use really inexpensive NPN transistors to do the switching for you.

I did get a response from Mesa, but they had no details for me:

In talking to our tech, he doesn't know exactly what the voltage is across the switching jacks- he suggests that you measure it, as we do not have one here to do so. - michael taylor :: product specialist