Footswitch for MR-8 // adding "live" capabilities to a digital recorderI've had a Fostex MR-8 digital multitrack recorder for probably five years now, and it's really worked out well for me as a tool in the studio, as well as on-site. But recently I was scheduled for a live gig and wanted to trigger some prerecorded backing tracks on the fly - to spice up my typical "me and my acoustic guitar" act. Now, the MR-8 has a footswitch capability for punching in and out during recording... but what I needed to do was start and stop playback via a footswitch - which on this machine was a no-go.
Well I wasn't about to let that stop me. I mean, if you push the buttons with your hands, how hard can it be to wire in some switches you can push with your feet? So here we go... into the Fostex MR-8.
[p mr8_inside.jpg A look inside the MR-8]
As with most equipment, it's just a matter of a few screws and you're in. It was a simple matter to locate the "play" and "stop" switches on the control pcb, so once I disconnected a couple ribbon cables and removed the shielding from the back, it was ready to be worked on.
[p mr8_pcb.jpg The main control pcb]
In general, I knew that all I had to do was wire my footswitches in parallel with the buttons on the board. This way, both the footswitch and the buttons would operate the machine. Once I was able to locate the common point of the two switches on the board, I simply soldered some wires onto the back of the pcb and over to a stereo mini jack I installed on the back of the machine. With one common, this allowed me to wire two switches (one for stop, one for play) with a 3-conductor jack... very nice.
[p mr8_wires.jpg Wired into the board] [p mr8_back.jpg My new jack on the back (far right)]
Being short on time and resources, I then proceeded to construct the most ghetto foot pedal I have ever made. But it worked out quite nicely.
[p mr8_footswitch.jpg My lovely foot pedal]
And there you have it! A digital recorder you can start and stop hands-free. Prerecord some tracks to jam along with and get as creative as you like!