Posted by Jay Bertolet on March 10, 2003 at 18:04:23:
In Reply to: Two-Way-Trigger??? posted by Tony R. Igger on March 10, 2003 at 13:36:08:
I think it was Gene Pokorny who was working with somebody (don't remember the exact name) that was marketing a device called a "Pitch-Finder". This was exactly what you describe. It attached to the main tuning slide and was adjusted to put the slide into a "zero" position. The device was spring loaded and, supposedly, would adjust the pitch nearly a quarter tone in either direction. After pushing/pulling to device for the desired note, you simply let go of the lever and the springs brought the slide back to the "zero" position automatically.
The Pitch-Finder was originally designed for trumpet and they became so popular that the guy started seeking out professional endorsers for versions for other instruments. I seem to remember Gene being the tuba guy. I was very interested in the concept but I could never find a tuba version to buy. The design seems to have disappeared at this point but you may be able to find someone who has one. I never really searched that hard myself so you might get lucky.
My opinion for what it's worth...