Hi All, I'm not sure how many people will be interested in seeing
this, but I shot a couple of short videos that show a simple invention
of mine that I use for testing the valves and pouches in the modern
Universal player piano. The videos are located at
I was a bit surprised to find out how fast the valves and pneumatics
could actually cycle with this simple device -- around 200 Hz!
John A Tuttle
Brick, NJ, 08724