[GreenKeys] ebay "Teletype Message Numbering Module"

[David Burns]

Well...there we go!  Thanks for the description, Jim!

The edge of the message numbering wheels are shown at the bottom of the 
second picture.

I'm holding out for price reduction, myself!

-Dave in Boston

On 1/8/2014 11:08 AM, Jim Haynes wrote:
> Teletype (and Western Unioni and Kleinschmidt) made message number 
> generating and checking machines.  In the case of this one the seller 
> didn't provide a front view, which should show wheels displaying the
> current message number.  These have cams to operate switches to
> encode the digits as Baudot characters.  The stepping switch in
> the middle sequences the characters and usually a wired-in channel
> identification.  The Teletype ones were typically used in torn tape
> switching equipment.
>
> You may be familiar with an earlier technology using the Teletype MXD
> 3-headed tape reader, where one of the heads held a tape containing
> the message numbers and channel identification.  Since it's a drag to
> punch such a tape manually, without errors, and since the tapes wear
> out, the mechanical numbering machine is an improvement.
>
> Western Union back in the 1940s had a message numbering machine with
> cam-operated switches.  Later they developed one using all stepping
> switches.  I'm not sure why - seems like it would have been much more
> costly to make that way.  This used a panel of neon lamps to display
> the number.  W.U. also used similar machines to check incoming message
> numbers automatically.
>
> jhhaynes at earthlink dot net
>