Fw: [GreenKeys] TTY protocol

[Dave Meier]

Sam,

Sure, I should have done that up front: http://en.wikipedia.org/wiki/AFTN

Just for info, I Googled "NNNN ZCZC" first and just got a slew of messages
with those chartacters in their text.  Then I Googled "definition: NNNN
ZCZC" and the infomative wikipedia article entitled "Aeronautical Fixed
Telecommunication Network" floated up to the fourth hit.  In this case, the
Google "Definition:" function kind of helped filter out the noise of less
relevant hits.

Dave Meier N4MW
www.n4mw.com

----- Original Message ----- 
From: "Sam Hallas" <s.hallas at ntlworld.com>
To: "Dave Meier" <n4mw at msn.com>
Cc: "Greenkeys" <greenkeys at mailman.qth.net>
Sent: Sunday, August 17, 2008 2:19 PM
Subject: Re: [GreenKeys] TTY protocol


> Dave Meier wrote:
> >  I found a wikipedia entry which explained this.  It also said that
> >  the NNNN punched hole pattern was just a series single hole punches
> >  to be easily identifiable to the operator as the tear point.
>
> Dave, I couldn't find the article. Could you post the link, please?
>
> I have a feeling that the use of ZCZC & NNNN predates WWII and most
> likely started with the cable operators like Cable & Wireless, where
> torn tape relay was widely used.
>
> Cheers,
> Sam
>