Need Midi Interface for Viscount/Baldwin/Rodgers Keyboards

I purchased three keyboards off Ebay that were described as coming from a Rodgers organ. I posted pictures on Facebook and several folks identified the keyboard as exactly like their Viscount and Baldwin.

Now that I have received and dismantled the keyboards I find that each uses a circuit board with silicon switches so I assume it is a matrix. But the connector on the keyboard has 20 pins. I have (hopefully) attached photos.

If anyone has experience with this particular keyboard, I would like to know how you were able to 'midi-fy' it.


https://photos.app.goo.gl/8vpwgTfYVLshwPsC8

https://photos.app.goo.gl/EChu1NRzJwp9wzom9

https://photos.app.goo.gl/41NGpQqrCUWbHKxv9

https://photos.app.goo.gl/ieLbkjq2ucaJMBZHA


Thanks, as always.

Hello David:

I am not familiar with the inner workings of a Viscount/Baldwin. However from your pictures, I think those called "Micro MaTch" connectors (yes with a capital "T"). Standard Fatar keyboards that you can purchase from Arnold organs, CMW, or MidiBotique have two16 pin connectors on the bottom. MidiBotique makes a MIDI encoder that plug-n-play.

However, from your pictures, yours are 20 pins. So I'm guessing these may not be Fatar keyboards or the just the basic key action is Fatar and Viscount developed their own proprietary circuit board. The extra pins could have been used to matrix in some standard pistons?

For what it;s worth, I had a colleague take an older Allen keyboard that had a Scan Matrix layout that was somewhat unusual. He gave up trying to get an encoder board that would work successfully so he cut out the diodes and went with discreet wiring (from Scan Matrix to Scan Row). This probably isn't an option with these Fatar keyboards given the wave soldiering manufacturing. I could be wrong.

Good Luck and let us know the progress.

Danny B.

I don't think it will be easy. Those contacts either probably generate a variable voltage, or have two contacts in there, and that's how the board generates a velocity midi signal. I think there are others that know how they work better, either here or at the Organ Forum. The wild card is that IC chip on the board. Does it have a number on it? If not it's proprietary, and you might as well pull it out and put some pin contacts there. Then you can test the contacts to see how they work with the diode meter or resistance meter on your multimeter. Then the only way will probably be to program an Arduino to sense the switches. You probably won't need all the pins if you're not using the IC chip. I can help you program the arduino, but the sketch will have to be modified according to how many rows and columns in the matrix, and what kind of switches it has.

If the IC is something recognizable, you may be able to use it, but that's above my skillset! Coenraads on the organ forum knows a lot about this though, so you can try posting there. You'll also need an Arduino for this. To my knowledge, no one has ever tried to reverse engineer these.

I agree they don't look like Rodgers, maybe a Rodgers branded Viscount (I think there were some of those once, in the early 90's!). They aren't the highest quality keyboards, so maybe not worth the effort. If you can get some wood core Allen ones, that will be much more forgiving to convert and satisfying to play!

That does indeed look like a Viscount keyboard. As far as plastic keyboards go, they are quite nice.
Six years ago, I “gutted” and “Hauptwerk-ised” a beautiful 3-manual Viscount organ that had died and whose owner was about to take to the tip because Viscount wanted silly money to even look at it, let alone fix it.

There are two diodes for each key but since you don’t need velocity-sensitivity you only need to use one of them – preferably the “lower” contact so that the note only sounds when you fully depress the key, and not when you accidentally brush it.
Because there are 2 x 61 key contacts on each original keyboard you have a pair of red MicroMatch connectors – one for the treble notes and one for the bass notes. Micromatch connectors can be pretty temperamental so it's best to leave them intact and try to tap into the flat cables from them.
Basically, the trick is to re-wire each keyboard into a single 8x8 matrix and install a single 16-way IDC connector to connect them to a suitable MIDI encoder such as a Midiboutique HWce2x or an Arduino.
I achieved this by hacking into the existing flat cables and by also removing the IC chips so that I could solder wires to the circuit boards.
Tracing the circuits from the key-switches to the diodes to the chips took a while, but once you manage it for one key it sort of falls into place.
Hopefully you’ll be able to access these photos and get some ideas:

https://1drv.ms/f/c/91b25ac08dd89943/EkOZ2I3AWrIggJGGAgAAAAABNkP4si0TNq_U84FB-HhlNg?e=7SVKT0

Graham

Further to my last post:
Having looked again at your photograph showing the rubber contact strips on the green side of the circuit board, and having counted the diodes in the photo of the other side, I guess my comments regarding velocity sensitivity and 2 x 61 key contacts on each board do not apply to your scenario. But the same principles for re-wiring the keyboards still apply.
Yours should be somewhat easier to do than those those that I worked on!

Graham

I just wanted to let people know that I was successful in midi-enabling this keyboard. Just briefly, it turns out it came from a Baldwin C-380 (manufacturer by Viscount). I removed the switches from the piston rails and installed thin pushbutton switches (from China) that have an illuminated ring. Since I exclusively use the Paramount 450, I added 12 Keycheek buttons for sound effects. All the midi electronics are from Roman Sowa at Midi-Hardware in Poland, who was really helpful. I also got great assistance from this Forum and from the Hauptwerk groups on Facebook.

Here is the final keyboard stack.

https://photos.app.goo.gl/Fp9RcifZNRdEXZ3z9

Next step is a plexiglass music rack and my previously-built stepper rail. These things are never finished!