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The Telecom Digest for Wed, 28 Dec 2016
Volume 35 : Issue 195 : "text" format

Table of contents
Re: Telex and TWX HistoryNeal McLain
Re: Telex and TWX HistoryBill Horne
Re: Telex and TWX Historyr.e.d.
Re: Telex and TWX HistoryHAncock4
---------------------------------------------------------------------- Message-ID: <52a31ea3e99b00cb6c394da05edbd2ca.squirrel@email.fatcow.com> Date: Mon, 26 Dec 2016 16:18:26 -0600 From: Neal McLain <nmclain.remove-this@and-this-too.annsgarden.com> Subject: Re: Telex and TWX History On Sunday, December 25, 2016 at 11:17:01 AM UTC-6, Bill Horne wrote: > Donald E. Kimberlin > Telex certainly should be called the original form of E-Mail. > Far from "dead" on a global basis, UN reports published in the > "Brittanica Book of the Year" indicate there are about three > million Telex lines around the globe. [snip} The quoted article states: > Because it was using the Public Switched Telephone Network (DDD in > American parlance, TWX was given reserved area codes... 510, 610, 710, > 810 and 910. Some few remote locations on TWX are still on those area > codes. Not any more. Those codes were recovered from TWX network and reassigned for POTS voice service during 1992-94. During the same period previously-unused codes 210, 310, and 410 were also assigned. As we all know the Great Area Code Format Change occurred on 1/1/1995. Prior to that date the original 144 area codes were confined to two formats: N1X and N0X. Starting 1/1/1995 new codes could be assigned with the middle digit in the range 0-8. But in the years just before the magic date there was a big demand for new area codes so the N10 codes were assigned:
210(previously unassigned) - assigned to San Antonio, TX area, split from 512
310(previously unassigned) - assigned to Los Angeles area, split from 213
410(previously unassigned) - assigned to Eastern Maryland, split from 301
510 (recovered from TWX) - assigned to Oakland and East Bay area, CA, split from 415
610 (recovered from Canada TWX) - assigned to Philadelphia area, split from 215
710 (recovered from TWX) - assigned to Government Emergency Telecommunications Service in September 1994, covers entire United States. http://tinyurl.com/710-GETS
810 (recovered from TWX) - assigned to east central Michigan, split from 313
910 (recovered from TWX) - assigned to southeaster North Carolina, split from 919
Source: Wikipedia http://tinyurl.com/NANP-N10 Neal McLain ------------------------------ Message-ID: <20161228032046.GA10402@telecom.csail.mit.edu> Date: Tue, 27 Dec 2016 22:20:46 -0500 From: Bill Horne <bill@horneQRM.net> Subject: Re: Telex and TWX History On Mon, Dec 26, 2016 at 04:18:26PM -0600, Neal McLain wrote: > On Sunday, December 25, 2016 at 11:17:01 AM UTC-6, Bill Horne wrote: > The quoted article states: > > Because it was using the Public Switched Telephone > > Network (DDD in American parlance, TWX was given > > reserved area codes... 510, 610, 710, 810 and 910. > > Some few remote locations on TWX are still on those > > area codes > > Not any more. Those codes were recovered from TWX network and > reassigned for POTS voice service during 1992-94. During the same > period previously-unused codes 210, 310, and 410 were also assigned. When I was in "Toll Test" at the Back Bay CO in Boston, I would sometimes have to test the dedicated lines that carried TWX dial tone from the TWX CO at "Boston 2", which was known as the "WADS" office, and had been leased to Wester Union after AT&T divested TWX. We had a Model 35 ASR Teletype there in the office: it had been used on TWX when AT&T had the service, but all the "official" machines, which were used for time sheets and other daily reports, had been set up with regular dial tones and were no longer part of the TWX network. Because the "TWX" machine in our office wasn't on the TWX network anymore, I had to figure out how to dial into the TWX network to send test message to Western Union customers whom were complaining about garbled characters and other "data" problems. It wouldn't work if I dialed a "710" or other TWX number directly: my teletype would only print garbled nonsense. I found out that there had been two versions of TWX, and the original system was, like TELEX, set up using BAUDOT machines running about 60 wpm. Of course, when the "100 speed" ASCII machines were introduced, they had to interoperate with the older BAUDOT machines, so the calls to 100-speed units from the older 60-speed machines were served only via WADS offices, which were equpped with speed and code converters that would translate between BAUDOT and ASCII, and do a speed conversion in real time. In order to tell 60-speed and 100-speed machines apart, any call form the "regular" DDD network to a 100-speed machine (the ones with the newer x10 area codes) was automatically converted from Baudot to ASCII code, and the speed adjusted. That was the source of my problem: I was using a "100 speed" machine to call from a "60 speed" phone number, so the WADS office was trying to convert Baudot to ASCII, etc. It turned out that the x10 TWX area codes were actually reversals of the associated Terminating Toll Center (TTC) codes for the WADS offices that handled each region. So, a 710-123-4567 number, dialed from an ordinary DDD number, would be from an older 60-speed machine to a newer 100-speed machine, and the code converters would be used. However, if I used a tandem trunk line and dialed the call as 017-123-4567, then it would be completed properly, i.e., as a 100-speed to 100-speed call that didn't need any conversions. I don't know if /all/ the 100-speed machines had to be served directly from a WADS office, or if it was just the place where speed and code conversions happened. I invite anyone with first-hand knowledge to fill in the details. Bill Horne (Remove QRM from my email address to write to me directly) ------------------------------ Message-ID: <kYa8A.129942$NC2.53435@fx13.iad> Date: Mon, 26 Dec 2016 10:47:23 -0500 From: r.e.d. <rednospam99@mindspring.com> Subject: Re: Telex and TWX History For readers who may not have seen it, I re-publish here my post from some years ago: +--------------------------------------------------------------+ A bit off topic, but this thread reminded me of one of my favorite published papers (because of its sheer readability) and I could not resist bringing it to the attention of others, old and dated though it may be. Scrounge through the stacks of your local engineering library: Test yourself: how much do you know about international communications? [International numbering systems] Robrock, A. Italtel, Milan; This paper appears in: Communications Magazine, IEEE Publication Date: Dec 1989 Volume: 27, Issue: 12 On page(s): 38-40 ISSN: 0163-6804 References Cited: 0 CODEN: ICOMD9 INSPEC Accession Number: 3582708 Digital Object Identifier: 10.1109/35.41420 Current Version Published: 2002-08-06 Abstract We like to think of international telephone communications as `transparent', the successful outcome of 100 years of technical progress and standards setting, but the author shows us that it is not. The user still has to be something of an expert to understand how to make international calls, and there are chaotically differing numbering systems for telephony, telex, and electronic mail. We should be reminded that usability of services, not just their usefulness, is a critical component of communications. Simplicity, consistency, and rationality of service features and the `human interface' that allows users to invoke them should be a high priority for communications engineers as they work toward the integrated services networks of the future ------------------------------ Message-ID: <e4724164-93e1-4f4c-9464-2158937f3e90@googlegroups.com> Date: Mon, 26 Dec 2016 20:22:56 -0800 (PST) From: HAncock4 <withheld@invalid.telecom-digest.org> Subject: Re: Telex and TWX History On Monday, December 26, 2016 at 10:06:03 AM UTC-5, Bill Horne wrote: > In 1986, I was using Western Union's email service, which was IIRC > called "Easylink". It had such a gateway, and I used it to overcome a > serious problem while I was applying for a license to operate my ham > radio station in Ireland. I was able to send and receive Telex > messages to/from the Ireland radio governing authority, twice in a > single day, which would have, at that time, been unthinkable by any > other means. Thanks for posting that interesting historical article about Telex. I too wonder what remains in use today, 30 years later. Here are some additional historical tidbits: . On 2/26/1987 and 5/24/1988 the NYT reported that Western Union was losing large amounts of money and was close to bankruptcy. Their EasyLink service was cited as one of the reasons for the losses. . In the 1930s, AT&T began TWX, a switched teletypewriter communication service. Western Union always felt that should've been a WU service as TWX definitely took telegram business away from WU. In the late 1950s WU established Telex service in the U.S. and Canada. . In 1968, WU announced it would acquire TWX from AT&T. In 1968, Telex was a 50 baud/66.7 wpm/Baudot network with 26,000 subscribers while TWX was a 110 baud/100 wpm/ASCII network with 44,000 subscribers. . In 1971 WU acquired TWX. The facilities were to be leased from AT&T for five years, then transferred over to WU. WU would build a modern computerized switching network for it. . In 1977, the physical transfer of leased facilities began. There was new urgency, as AT&T was steeply raising its lease rates and that was hurting WU. (I recall reading that pressure from MCI for equal treatment didn't help matters). In my own opinion, the significant reductions in dialed direct toll rates, especially during overnight hours, that occured in the 1970s, reduced the value of a dedicated separate Teletype network. While I don't know how voice and TWX/Telex rates compared in the late 1970s*, one could pre-punch a tape and send a reasonable message in one or two minutes at a reasonable cost over the voice LD network, and short haul calls could be as cheap as 5c/minute. Also, private line computer networks were growing and could of course be used for messaging. *In 1950, voice long distance was much more expensive and telegraph was significantly cheaper, so far more long distance communciations was by telegraph rather than voice. I can't help but suspect the number of TWX/Telex subscribers fell off significantly between 1970 and 1980 and even faster after 1980 when used for domestic service. The big drop in overseas toll rates took a little longer, as described in this thread. ------------------------------ ********************************************* End of telecom Digest Wed, 28 Dec 2016

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