MOTM

Very cool, Frank. Does this device still exist? Of course this set up (minus 
the top octave generator) would be perfect for what we've been talking about 
here. Are these electromagnets available anywhere?

JB

In a message dated 12/28/2000 4:31:02 PM, fvanaman@... writes:

>My dad and I had some electromagnets, basically iron cores with many,
>many turns of wire around them, and we took a top octave generator
>(50204), fed into a series of divide-by-two dividers, which then fed
>what was basically a transistor pair-in-a-chip (ULN-2003?), which in
>turn was connected to the electromagnet. You could select the
>appropriate note, and drive the coil with a square wave-- holding it
>over the center of the correct bar would cause the bar to vibrate at
>it's fundamental pitch.