Automatic Wireless Afloat

R

Rosanne MacIntyre

Member
I found this article in the April, 1924 White Star Magazine and hope that the experts on the board can expand a bit on this new process. It almost sounds like a sort of teletype machine

"Automatic Wireless Afloat" was the caption under which one London morning paper dealt with the feat performed on board the Olympic during her voyage from Southampton to New York at the end of February. For the first time on shipboard wireless messages were automaticlly transmitted to London so that they could be actually printed in the G.P.O. without human aid. At 90 words to the minute, a speed transmitting apparatus sent messages over a distance of 700 miles to the land station at Devizes and the printed letters as they appreared at London were perfect.
 
Rosanne,

Automatic printers had been experimented with since before Titanic's time, but they had a history of being unreliable. In 1920, a new, reliable auto-alarm was demonstrated by the Marconi Co, and by 1927, the auto-alarm was mandatory aboard large, passenger-carrying vessels registered with the BOT. I don't know when Olympic received her auto-alarm, but I do know that in May 1923, she was fitted with a wireless telephone transmitter, so she may have received this new "Automatic High-Speed Transmitting" apparatus at about the same time. Yes, voice transmissions were becoming increasingly popular by that time, but distress calls continued to be sent via telegraph for quite some time...right up to the 1990s.

If you have the article, there is a wonderful photo of the interior of Olympic's Silent Room (the view is toward the aft, port corner) with this new apparatus. Too bad the older spark equipment had been removed by that time. As it is, I used that photograph as a reference for the panelling in my CG re-creation of Titanic's Silent Room.

Parks
 
So are you saying that this was voice transmitted from the ship to land? If you have a minute please explain the proceedure both from the ship and to the receiveing station.

I do have that photo and it is wonderful! I wanted to scan it and send it onto you but I copied the atricles from the NYC library's copies of the magazine and the photocopy came out dark

Rosanne MacIntyre
 
Rosanne,

No, the wireless telephone and the auto-alarm were two separate systems. The auto-alarm was still basically a telegraph. I was just speculating about when the auto-alarm might have been installed in Olympic...I know that it had to have been between 1920 and 1924, and it is reasonable to speculate that the auto-alarm might have been installed during the same period when the telephone system was being put on board. But, that doesn't necessarily have to be the case.

Basically, the auto-alarm system was designed to reduce the number of wireless operators required by the "continuous watch" system which was instituted after the Titanic disaster. The system itself consisted of an automatic transmitter (on the ship) and a reliable receiver (on another ship or land station). The operator in the ship in distress would press a key, which which would cause the transmitter to send a series of four-second "dashes." The special receivers would detect this unique signal, set off an alarm (during the system's demonstration in Chelmsford, the alarm consisted of a charge of gunpowder and flashing lights!!!) and automatically respond to the transmitting set, letting it know that the message had been received. Once communication had been established, then the operator could send the ship's position and additional particulars.

The entire reason for this device was to relieve the shipping industry of the need to maintain a continuous Radio Officer watch aboard most ships. In July 1927, the BOT formally approved the auto-alarm. The BOT regulations of 1 Oct 1927 laid down the relaxation of a continuous watch for those ships fitted with the auto-alarm. The BOT regulations were further codified during the SOLAS convention of 1929. Beginning 1 Jan 1933, ships provided with an automatic alarm device were only required to have an operator stand a watch for four periods of one-half hour each...0800-0830, 1200-1230, 1600-1630, 2000-2030. At all other times, the auto-alarm would cover the watch. The shipping industry was happy because they didn't have to shoulder the burden of employing two or more wireless operators continuously.

See what Titanic wrought?

Parks
 
Now, having said all that, when I re-read your initial post, I am wondering if I answered your question properly. The article from which you quoted refers to printed messages. That may or may not be referring to messages generated by the auto-alarm system. If not, then I'm not aware of the particulars of the described system. In 1924, I'm only aware of the following communication systems aboard Olympic:

- Long-distance Marconi telegraph system
- Marconi auto-alarm system
- Wireless telephone transmitter

If there was a means of composing and transmitting telegraphic messages to a distant station, where they would be automatically translated into readable words, then I'm not aware of it. I'm also not aware of a system that would transcribe voice broadcasts automatically. So, maybe I don't have the answer to your question, after all.

Parks
 
Parks,

LOL! Now, what was the question? The second paragraph of my original post was the entire article in the White Star Magazine. Having worked in USSteel years ago, the description of the process reminded me of teletype.

It seemed revolutionary the way they stated it as the "first time shipboard wireless were automatically transmitted to London...."

Thanks for your responses and know, I always appreciate your input and generosity sharing your knowledge with the board.

Rosanne MacIntyre
 
Rosanne, I'm no expert, but I've heard a little about a system that enabled the 90 words a minute transmission, which is much faster than can be done by a human operator.

I believe it involved several people making punch holes in paper tapes which were then fed through a machine that could send Morse at high speed. The actual transmission was the only part of the process that was fast. The message may have been received at the other end as holes in ticker tape or maybe they had a typewriter. I'd guess at the ticker tape, as typewriters of the time were not very flash.

There was a great deal of equipment around that was developed for telegraph work and presumably it was adapted for radio.

What we need here is an expert on telegraphy.
 
Parks, that's what Rosanne appears to be talking about. Reading up a bit, I'd suggest that they used, not Morse, but some form of the Baudot code, which was an early form of digital code. That would account for the speed and accuracy.
 
Dave,

If that's the case, then it's outside my area of expertise. Anything before my time and I have to refer to my reference material, which covers only Marconi equipment.

However, I read up on the "Baudot code" after reading your message. That's good stuff to know, especially since I'm doing a Modern Marvels segment next week on the history and development of military communications and this information might help me describe the transition from telegraph to TTYs.

Parks
 
The first radioteletype (RTTY) communication was accomplished with "make-and-break" transmission wherein the transmitter carrier was pulsed on and off in a fashion analogous to Mode A1 CW transmission. Instead of Morse characters, the pattern of "on" and "off" intervals used Baudot to encode the characters, which was standardized as CCITT Alphabet #2 in 1924. Functionally, the method wasn't very different from a "wired" teletype circuit, which used a pulsed current loop between machines. Make/break was rather error-prone (an atmospheric "pop" could be construed as data), so very soon the primitive carrier keying was replaced by a two-tone modulated carrier system (Frequency Shift Keying) wherein a "mark" was represented by a burst of one frequency, and a "space" by another.
 
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