On Nov 27, 2013, at 7:21 AM, N4BE_Jim wrote:
> http://www.ebay.com/itm/VINTAGE-CODE-PERMUTATION-TAPE-PRINTER-TELETYPEWRITER-TELEPRINTER-TELETYPE-/331075091839?&_trksid=p2056016.l4276
>
> What is this?
I have no direct knowledge of what this is... however, this may shed some
light...
Back before Howard Krum (you can see a reference to his patent in my "RTTY
Demodulator" article), Baudot was transmitted as 5 parallel data bits. Krum
invented the start stop system, where one single wire pair can send all the 5
data bits. I believe "permuted code" was one terminology that was common to
describe that back then (almost a century ago -- how time passes, HI HI).
So, this teletypewriter could just be old enough that it boastfully say that it
can accept the start-stop Krum system which we take for granted today.
However, this antique is probably also be less than 100 years old. Krum's
patent came out in 1918, and I don't think there was any "permuted code" before
then.
73
Chen, W7AY
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