From: Spehro Pefhany
Subject: Re: telex interface
X-Newsreader: Forte Agent 1.92/32.572
Date: Thu, 28 Nov 2002 18:36:03 GMT
NNTP-Posting-Date: Thu, 28 Nov 2002 13:36:03 EST
On Thu, 28 Nov 2002 13:26:42 -0500, the renowned "Peter O. Brackett"
>Wow is the Telex network still in operation?
>In the USA it used to be Western Union that ran that network, who runs Telex
>in the USA today?
>The line protocol... it's a simple DC 20 mA current loop driven by station
>DC battery [-48VDC] on-off keyed [OOK], runs asynchronous protocol, i.e. one
>character at a time, 45 baud, International Alphabet #2(ITU/CCITT 5 bit
>code). But you gotta know your WRU code, heh, heh... All of this is well
>documented in "old" CCITT documents, probably Yellow Book or Blue Book
Neat, so I was in the right ballpark. I can still remember 'chatting'
with a supplier in Japan, one character at a time
HOW R U?
Normally you (for some reason most companies had operators doing this,
it was considered too specialized for normal folks(!)) cut a paper
tape with the entire message and then ran the tape. If you made
mistakes you could null them out by punching a character that
consisted of all holes in the tape. You could then, if it was
worth it, run the tape through the reader and made a copy without
the money-wasting null characters. A typical Telex message might have
cost $5 or $10 to send to Asia. Now we can all receive graphic
pornographic spams from Asia for free- we've come a long way, in
I thought Western Union in the US ran the TWX network, which was
distinct from Telex, but you could send messages between the two
"it's the network..." "The Journey is the reward"
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