IBM ScanMaster

From: John Foust <jfoust_at_threedee.com>
Date: Thu Apr 5 08:53:53 2001

At 07:11 PM 4/4/01 -0400, you wrote:
>>> First fax machine was over 100 years ago with synchronized
>>> pendulums.
>
>>How do you synchronize to a remote pendulum?
>
>I'm stepping into memories now, including college physics,
>But, as I recall and understand, the pendulums would basically
>oscillate at the same frequency since they were of the same length.
>All that would be required is to send a synch pulse at the end
>of a scan (rough analog to TV VIR) to align the next full scan.
>The remainder body of the pendulum swing would be kept
>in tune using only the ballistic physics of the thing.

Pendulums could be sync'd by starting their swing at the
same time by a pulse on a control line (which would release
a catch that had held the pendulum at top-swing), and they
could be re-sync'd and their swing regenerated with a well-timed
pulse to an electromagnet at the apogee of the swing-path.
No doubt a great deal of early computing and fax technology
could borrow from clock technology.

- John

P.S. My youngest son is named Seth Thomas. :-)
Received on Thu Apr 05 2001 - 08:53:53 BST