Hi, i posted this on the other thread before i saw that the topic had been moved to here, so here is a copy of it,
Somehow in the back of my mind i remember a device, that was a small handheld Tesla coil. It had a probe that you would move around the object you were leak testing. If there was a tiny leak the air rarefied would glow giving a indication of where the leak was located. I 'll look on google and see if i can find more information about the name of the machine and any pictures, Logan
P.S. I found it and the factory is located a few blocks down from the old E.H. Scott radio factory in Chicago, whodathunkit?
http://www.electrotechnicproduct.com/