Fwd: Western Union TWX V Diagnostic Control Panel

[Christian Fandt]

I forwarded Joe's request for info on the TWX Diag Control Panel from the 
ClassicCmp (cctech) list to the Greenkeys email list. Both Joe and I got a 
private reply but I feel some others on both lists will be interested in 
Russ' reply. To wit:


>From: Russmill47 at aol.com
>Date: Mon, 4 Oct 2004 12:37:40 EDT
>Subject: Western Union TWX V   Diagnostic Control Panel
>To: cfandt at netsync.net
>Cc: rigdonj at cfl.rr.com
>
>
>When Western Union acquired the TWX network from AT&T, there was a need to 
>build a new network that would allow Western Union to integrate the 
>existing Telex network with the TWX network.
>
>Western Union designed and built the Digital Exchange Network (DES) for 
>this purpose.  DES was not the huge success that everyone hoped as there 
>were many software problems that caused reliability and availability problems.
>
>The TWX V Concentrator was located at the edge of the WU Central Office 
>network, usually within a couple of thousand cable feet from the serving 
>Local Exchange (Bell) Central Office.
>Typically, these concentrators would handle up to fifty (50) TWX 
>customers, handling all the edge interaction with the customer TWX machine 
>on one side of the box with the rest of the box providing TDM services 
>that consolidated the 50 customer signals into a single digital data 
>stream.  In small locations, which could be rental space in a telephone 
>answering service location, there would be a single box.  Medium size 
>locations would have multiple boxes that would feed their digital signals 
>to an intermediate box that would further Mux these separate digital data 
>streams to a high speed (9600 bps) Paradyne Modem.
>
>The Diagnostic Control Panel was mounted at the top of the concentrator 
>and was used to monitor the internal health of the box as well as provide 
>information as to the status of the individual subscriber links and the 
>high speed digital data link.  The technology is state-of-the art early 
>1970s so you can look to processor speeds of 1-2MBps.  A lot of this 
>technology was designed and manufactured in Mahwah, NJ.  This was the R&D 
>headquarters for WU and just up the road from WU galactic headquarters in 
>Upper Saddle River, NJ.
>
>Russ Miller
><mailto:russmill47 at aol.com>russmill47 at aol.com
>WA3FRP

So it appears the DES was one of the early implementations of commercial 
digital communication.

Thanks for the enlightenment Russ!

Regards,  Chris F.

NNNN

Christian Fandt,    Electronic/Electrical Historian
Jamestown, NY  USA      cfandt at netsync.net
         Member of Antique Wireless Association
         URL: http://www.antiquewireless.org/