[GreenKeys] AN/FGC-38 Torn-Tape Relay Equipment

Mon Aug 28 10:59:07 EDT 2017

Hi Duncan:

True, the teletype machine was in fact the ORIGINAL email device!

In the 1980s, before computers became common, Western Union came up
with something called INFOMASTER. Within the WU networks, there were
several databases containing all kinds of useful information that one could
call up: stocks, historical information, sports, etc. This was sort of like an
early form of "web surfing" where an op could print this info out for whatever
reason. You scrolled thru the database for whatever you were interested in,
and then, when it came up, you could call up the entire database and then
print it on the teletype printer (all or just part of it). Some of this stuff was
really long. The WU message switching center was located at Paramus, NJ.

I used to work at WU part-time after working in the CommCenter when I
was stationed at Fort Ord, CA. As I knew all of the WU guys who maintained
our circuits and equipment, it was easy to get work with them. My job there
was sending and receiving telegrams and money orders and sometimes,
working the "tie lines" which was sort of like a WU version of a military
Technical Control Center, but on a much smaller scale for private contractor
users, such as Nestle Chocolates, Smuckers Jelly, Amtrak, SP railroad,
PSA and United Air Lines, etc..... all of whom used WU lines and leased 
Model 28s for thier work. Air Line and SP freight train manifests were always
interesting as traffic was continous at times. (SP also owned Sprint at the
time, which was a CAlif mountain top and line-side train crew/dispatcher commo
system before it was sold off and became a telephone company). Sprint 
was patterned after the Pennsylvania Railroads' "train phone" system of the
1950s which was also used by the Kansas City Southern Railway....before
VHF radios and repeaters came in to vogue..

Working the tie lines, you could always plug in (via a patch panel) and 
monitor and copy everyone's traffic at will going across the teletypes....
probably an early form of "hacking" back then, but we considered it part of
maintenance.....you could also "talk" (type) online back and forth on these lines,
if it was necessary, but we only ever did that if a WU tech was on site
at the customers end. The customers did not use the tie lines (sort of like
an Order Wire). They only sent and received company traffic over these
lines and equipment.....

Opening comms used a function on most WU machines called "WRU"...
"Who Are You"....and either a tech would manually type back who he
was, or there was a short pre-made, canned response in the machine at the
distant end....which told you what customer and which teletype/circuit was being
worked (assuming they had more than one teletype, which most did).

Dave

# # #

-----Original Message-----
From: Duncan Brown <duncanancy at earthlink.net>
To: greenkeys <greenkeys at mailman.qth.net>
Sent: Mon, Aug 28, 2017 9:54 am
Subject: Re: [GreenKeys] AN/FGC-38 Torn-Tape Relay Equipment

Paul,You said " a real challenge to get from the receiver to another transmitter without a snarl-up"When a message came in, it would be torn off of the reperforator (hence the term "torn tape relay") and walked (or tossed) to a tape reader bank for re-transmission.Although I did hear of a story of a tape relay center where a high priority message came in that had to be relayed to multiple addressees immediately. So the tape came out of the reperforator and was fed directly into a tape reader and then, sequentially into other tape readers. But that was not the norm.Your "running out of tape in the middle of a message " question is a good one, that I never thought about before.  I never worked in a big tape relay center, but helped build & test a transportable one for the Army.  I think the answer is that there would be a bank of reperforators and when one started showing the end of tape, it would be switched off-line and another would be switched/patched into that circuit.A roll of tape would last about 5 hours at 60 wpm and about 3 hours at 100wpm.On the ALL CAPS of the early machines - the generic name for your M15 (and earlier units) was a "printing telegraph" (Teletype Corp used this term up into the mid 1950s).  The main user of the early TTYs was Western Union & other telegraph companies and they started replacing their telegraph circuits with TTYs. But a message might travel through both Morse and TTY circuits. The Morse telegraph code did not have lower case letters, so there was no need for the printing telegraphs to have them, either.AT&T bought the Teletype Corp in 1930 to have machines to lease out for their new TWX (TeletypWriter eXchange) service. (In Europe, it was known as TELEX.) This service allowed TTY users to communicate with anyone else on the AT&T TWX network, just like the telephone exchange service.  Tell your daughter that your M15 is the _original_ e-mail device!Have fun,Duncan Brown, K2OEQUSASA  31J30Antique Wireless Association Museum Asst. Curator, Commercial Equipment(also Chief TTY operator & repairman)http://www.antiquewireless.org/On 28-Aug-17 02:39, Paul Birkel wrote:>> Thanks Dave.  More great info!  A “couple of hundred feet” would seem > to be a real challenge to get from the receiver to another transmitter > without a snarl-up.  What’s to preclude “over-running” the pink > tape-end-coming-soon indicator and having a tape run-out before a > message completes?  Just monitor the receipt, accept that sometimes > this will happen (like various categories of receiver mechanical > problems) and ask for a retransmit should that happen?  Did the > sectioning policy manage to avoid this, by keeping the tape-length for > a section less than the pink-length?  Under heavy traffic conditions > how long would a tape-roll last and how did you manage to avoid > running out of tape mid-message?>> (And, alas, I was never able to get my Morse Code proficiency up to > the point of passing a radio license exam as a kid.  Now it’s all > “ancient history” …)>> One aspect of all of this has been the realization (understanding) of > why USMTF looks the way it does, SCREAMING CAPS :->.  I grew up with a > 33ASR (and minicomputers) in the 70’s and simply didn’t know of the > earlier Baudot era.  Store-n-forward packet-switching was the > new-thing for computer-communications then.  Its heritage from an > earlier technology was either unreported, or I simply missed it in my > education.>> This whole earlier era is an eye-opener for me.  I’m pleased to report > that I’ve recently become the proud recipient of an M15 and table that > was passed along from another list member, so it’s no longer “just > academic” :->.  I’ve not yet gotten to the point of putting it into > service, but it’s an absolutely amazing piece of equipment to examine > close up.  Had a bit of show-n-tell with my adult daughter last > month.  Even as a “still life”.>> Thank heaven for Greenkeys!>>---This email has been checked for viruses by Avast antivirus software.https://www.avast.com/antivirus______________________________________________________________GreenKeys mailing listHome: http://mailman.qth.net/mailman/listinfo/greenkeysHelp: http://mailman.qth.net/mmfaq.htmPost: mailto:GreenKeys at mailman.qth.net2002-to-present greenkeys archive: http://mailman.qth.net/pipermail/greenkeys/1998-to-2001 greenkeys archive: http://mailman.qth.net/archive/greenkeys/greenkeys.htmlRandy Guttery's 2001-to-2009 GreenKeys Search Tool: http://comcents.com/tty/greenkeyssearch.htmlThis list hosted by: http://www.qsl.netPlease help support this email list: http://www.qsl.net/donate.html
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