[GreenKeys] Alexander Graham Bell System Electric Motor 12-AL - eBay (item 110296287858 end time Dec-03-08 17:34:04 PST)

[Douglas W. Jones]

On Nov 6, 2008, at 1:04 PM, Larry Tighe wrote:

> Can anyone tell me what this did...once upon a time?

Looks like it generated some kind of timing signals.  The
contacts sliding on the face of the flywheel at one end
would produce a constant pulse stream.  The drum on the other
end with the row of 7 contact fingers looks like it would
have had an insulating sleeve on it with, probably, holes or
slots cut in it to produce a programmed series of pulses, but
only when enabled by a start pulse to the coil a the
bottom -- the presence of this coil suggests that the
"music box" mechanism must have been driven by a slip clutch
from the right-angle gear driven by the motor.

All of this, taken together, suggests something like a special
purpose machine to respond to WRU (ENQ) requests, comparable
to the music-box mechanism of later teletypes.

It's similar to some Kleinschmidt gear I've seen, designed
to slide into a mounting frame, with a "card edge" connector
made of individually screwed-down contact fingers.

		Doug Jones
		jones at cs.uiowa.edu