[simpits-tech] Pneumatic controllers

[Matt Bailey]

Howdy,

   I recall some time ago a discussion about setting up a closed pressure 
system to control real altimeters and VSI's, using electronic pneumatic 
controllers (in fact I still have a video on my HD of an altimeter being 
controlled in this manner). I was just wondering if anyone had any info on 
this, like what kind of controllers are required, what kind of signal they 
use, how they function, etc.

	-Matt Bailey