Scratch Markup Language Fader Hack

In the case of the PMC-07 Pro the voltage that is sent to the crossfader is 10V DC. We used an Arduino Uno to monitor the voltage. It maxes out at 5V. Not wanting to explode the Arduino with 10V we used a simple voltage divider on each channel utilizing two (four total) 1 megaohm resistors. We would have been a lot better off using 100 kilohm resistors. Using an opamp would have been even more betterer but… we didn’t have any of those.

Because we’re so damn pro and didn’t have any of the parts to make a proper Y cable we just soldered everything to the crossfader.

Simple! Follow these amazeball instructions. The PMC-07 Pro uses a 4 pin connector on the crossfader. The outside pins are power and ground the middle pins are for the channels. Use a volt meter to determine which pin is power and which pin is ground. Plug ground into one of the ground pins on the Arduino and the two center pins from the fader through a voltage divider and into two analog pins on the Arduino. We used A0 and A1. You do not need to hook anything up to the 10V power pin on the mixer. Got it?

CLICK TO EMBIGGEN

The Arduino sketch we used can be found here.

In summation here is a list of items you must procure to do this:

• Vestax PMC-07 Pro mixer (Any VCA mixer will do, just drop the voltage to 5V or less.)
• Four 100 kilohm resistors
• An Arduino
• A proper Y cable for the PMC-07 Pro. Instructable for building it is here
• Arduino sketch found here

Build your Y cable. Make a couple voltage dividers. Hook it up like the picture above and BLAMO!

#Pro-Tip: Elliot Marx informed me that if you use an Innofader (the origional, not the Pro or PNP) it will limit the VCA voltages of the PMC-07 Pro to 5V eliminating the need for the voltage dividers. Wire colors for the Innofader are as follows:

Blue = 5V
Green = VCA1 (varies from 0 to 5 volts)
Yellow = VCA2 (varies from 5 to 0 volts, moves opposite from VCA1)
Grey = ground

Thank you Elliot!