[SmokeTest]

This is bit off-topic, but I think the reason the MA3 isn't more popular is that all prior Operator Interface controllers had a dead band programmed into it. The IFI Robotics manual says:
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Digital value response for approximate analog input values: Digital 127 for 0.0v to 0.1v.
Digital 0 for 0.11v to 0.52v. Increasing from digital 1 to 254 for 0.53v to 4.99v.
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Imagine rotating the knob from from 4.8V, 4.9V, 5.0V, 0.0V, 0.1V, 0.2V, etc. The OI software reports 252, 253, 254, 127(!), 0, 0, 0, ... then finally starts incrementing past 0 after about 40 degrees. This kind of behavior makes sense for a joystick, but not for the MA3. [The reason 127 corresponds to 0V is to stop a motor controlled by a Victor when a joystick gets unplugged.]

How to avoid this dead zone had me stumped all during build season last year, but I finally figured out a simple kluge to change the voltage at the analog input to avoid the 0V - 0.52V dead band. I added a diode (forward biased) between the ground lead of the MA3 and the ground pin of the OI. At the 16 mA current drawn by the MA3, the diode's forward voltage was about 0.6V. This made the minimum voltage at the input pin (output of the MA3) about 0.6V relative to the OI. From the MA3's point of view, it thought it was going between 0V and 4.4V, but it's shifted by 0.6V because of the diode's (relatively) constant voltage drop. US Digital specifies a minimum supply voltage of 4.5V for the MA3, but it worked for me at 4.4V. (That's why I call it a kluge.)

As I said, this might be a little off-topic now with the new Driver Station controller, but if anyone wants to retrofit an IFI Operator Interface controller with the MA3, you might want to try this trick.