[GreenKeys] Help dating early Model 14

[Duncan Brown]

Harold,

Nick gives a lot of references for Ton-tape systems.  The AWA video was 
my idea and I was the one who got the M28 RT working, but the video was 
put together and narrated by our video guru, Mark, AE2EA.

To answer some of your specific questions:

On 1/22/2026 12:55 PM, Harold Hallikainen via GreenKeys wrote:
> On torn tape relay, I THINK there was a reperf on each incoming line, and
> a TD on each outgoing line (and these may be the same wires through
> duplexing techniques).
Yes, but no duplexing of TX & RX on same line.
>   So, did one person watch several reperfs for end of
> message, tear the tape, and take it to the appropriate TD?
Yes
> Was the TD sitting there idle?
Depends on how much message traffic there was.  Could be idle at times, 
and other times have a big backlog of messages.

> Perhaps new torn tape would be spliced to the existing torn tape waiting
> to be sent. Or, the whole thing could be automated entirely
> electromechanically.
As Nick's demonstration shows, there were typically two tape readers per 
circuit. Individual messages were loaded into each one and when one 
finished, the next one would start automatically.

>   Each message would have a series of routing codes at
> the beginning of the message. The receiving unit would decode the first
> routing code (possibly using a distributor and a bunch of relays), then
> pass the remaining message (with more routing codes) on to a reperf that
> is continuously feeding a TD on an outgoing line. The reperf/TD would be
> an electromechanical FIFO buffer.
In the manual systems, routing information was read by and the tape 
physically routed by an operator (aka "Tape ape"). In the automatic 
systems (which there were very few of) the message would be buffered (on 
tape) while the routing information was read and a path to an outgoing 
tape reader was set up.

> So... how did relaying work, and what was its history?
The torn tape relay system was used from about 1944 up into the 1980s, 
by US Military, Government, Western Union & others.


Hope this helps,

Have fun,

Duncan
K2OEQ
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mailman.qth.net/pipermail/greenkeys/attachments/20260122/b982178e/attachment.html>