Quite A number of (Years or Moons ago) depending on how you keep track of
time, someone came to one of the hamfests in Gaithersburg, Maryland, in a
large box
type of truck, and mounted on top of the truck was a CAPACITOR CANNON of
sorts.

I think that I need to clarify a bit - apparently the capacitors did not
really explode, but SNAPPED IN DISCHARGE STATE causing a louder than life
noise, and could be recharged to do it continuously.

At a push of a button this object sounded like a number of VERY LARGE CHERRY
BOMBS going off in succession.

Yes - it was an attention getter.

Does anybody else remember this device and or have a schematic for it?

73's