Nice to know the olde AFTN is still chugging along!
(I used to write software for AFTN systems but Russia was not a client.)
Nice to know the olde AFTN is still chugging along!
APL or Fortran?
ZCZC LAA005 12032000
DD OPKCZQZX
120900 OPSTZQZX
MESSAGE TEXT
NNNN
TheGreenGoblin wrote: ↑Thu Mar 31, 2022 6:39 amAPL or Fortran?
Ah I see it is an X.25 link meta-language, full of arcane ACKS and NACKS governed by the hierarchy of ICAO codes and location addresses.
It uses lots of Z's so Putin will be happy anyway...
ZCZC LAA005 12032000
DD OPKCZQZX
120900 OPSTZQZX
MESSAGE TEXT
NNNN
You would understand the need for the ZCZC if you were familiar with the Murray/Baudot code and how the telegraph machines of WWII era operated.
Incidentally, the Soviet delegates at the technical meetings in Montreal c. 1985, were at pains to ensure the end of line function included two carriage return signals which gave the mechanical printing mechanism time to return even at speeds as low as 5 characters per second.
John Hill wrote: ↑Thu Mar 31, 2022 8:48 am
You would understand the need for the ZCZC if you were familiar with the Murray/Baudot code and how the telegraph machines of WWII era operated.
Incidentally, the Soviet delegates at the technical meetings in Montreal c. 1985, were at pains to ensure the end of line function included two carriage return signals which gave the mechanical printing mechanism time to return even at speeds as low as 5 characters per second.
Ah yes, EBCDIC and the world of IBM which I was lucky enough to stay almost clear of except a somewhat brief encounter with 3270 protocols and machinery.TheGreenGoblin wrote: ↑Thu Mar 31, 2022 9:20 amJohn I see that this Admin2 guy is more of Control + kind of guy. More EBCDIC then ASCII though!
I better watch myself lest I am terminated by that gentleman with the old (CTRL-D)- 0x05 EOF marker.
I do understand that. I was just linking my experience of the hardware with the use of ASCII code. The Baudot character coding (5 bits) goes back to the 19th century.John Hill wrote: ↑Thu Mar 31, 2022 9:26 amYeabut you are mixing the physical with the errr, etherial. RS-232c is a standard defining the signal levels on a cable whereas ASCII and Murray/Baudot defines character codes. I built many systems using Murray/Baudot on RS-232C connections.
Much of the international AFTN was still using Murray/Baudot codes and mechanical teletypewriters when IBM PCs became cheap and available. Integrating the PCs in to the AFTN network required considerable lateral thinking!
The challenge faced by telegraph engineers of the Baudot and Murray era was synchronisation between sending and receiving ends then around about 1926 some chap whose name I forget invented 'stop-start' signalling.
John if we carry on like this we will end up discussing Martin Hollerith et al...John Hill wrote: ↑Thu Mar 31, 2022 7:29 pmWhile we are in pedant mode would you please contact Britannica and correct them..
https://www.britannica.com/topic/code-communications
"One such system was the Baudot code, which encoded complete phrases into single words (five-letter groups) for use by telegraphers."
I suspect they are referring to Bentley's code or something similar.
I am sorry but I will not be able to travel to Orkland but if ever we do meet I hope we will have time to discuss the work of Agner Erlang.TheGreenGoblin wrote: ↑Thu Mar 31, 2022 9:03 pmOn the comms front I have just pulled out my dusty textbook on the mathematics of information and communication modelling ref. Shannon and Weaver... something to discuss over a beer in Auckland one day.
We only have enough money for an 8 bit room!
I was an RAF Boy Entrant u/t Telegraphist II at RAF Cosford 1959-61 and "man's service" 1961-73. We were taught to touch-type and to send/receive Morse code at 18 wpm. Equipment in use for non-Morse was 50 baud teleprinters and torn tape relay procedures. We had to memorise ITA2 (eg 12 = A or -, 15 = Z or +, 1235 = Q or 1, 1245 = FIGS, etc) and it was useful when I joined GCHQ as a Radio Officer after demob, reading UG8 undulator tapes (Morse and ITA2) was a new experience!John Hill wrote: ↑Thu Mar 31, 2022 11:21 pmMeanwhile AFTN 1955........it is a lot to demand but maybe this will work.
https://fb.watch/c5Y3weVSYY/