I’ve seen them in old newsreels, Scrooge McDuck comics and, more recently, the Irish mafia odyssey Road to Perdition. You know what I’m talking about: those little glass-domed typewriter-lookin’ things that rich men of the early 20th century kept in their stately offices so that an eye could be easily kept on the ol’ finances. Pretty cool, if you ask me.
However, something’s always bugged me about them. These personal tickers seem to have reached their height of popularity in the '20s, and yet they seem to be, technologically, pretty far beyond any other machine from that decade. How, I wonder, was a machine able to automatically receive, decode and print up-to-the-minute stock symbols and quotes in an era when traveling to Europe might well have cost one their life?
How were the quotes transmitted?
How/from where were those transmissions sent?
How did the machines receive transmissions?
How did they convert the transmissions into printed quotes?
Well, in an effort to stave off the rapidly-aging “death ray” joke, said stock tickers worked like a “printing telegraph”.
The way I understand it- I read something brief about them many years ago- the printout is coded, if not actual Morse Code, each stock using an abbreviation (much as they do today) in order to make transmitting and decoding quicker and easier.
Basically the telegraph, at it’s simplest, was a set of electromagnet coils and a contact. You tapped it here, which charged the coils over at the other end, causing the tapped to click down, making a noise. The reply tapped their contacts, making the coils clack the tapper at your end.
Think of it as primitive binary- trying to pass data by a simple on-or-off analog signal.
The Stock Ticker was simply a fancier version that had a small mechanism to advance a roll of paper when the tapper cycled, and a small punch in addition to the contacts, to mark the paper. I’m not sure if any of them actually typed real words or numbers, I believe they were all Morse-based printouts.
The Edison Ticker Tape machine on this page appears to have a rather broad tape with possibly more than one line of information on it - almost like a sort of primitive dot-matrix, or am I seeing something that simply wasn’t there?
As noted above, “tickers” were merely “printing telegraphs”, i.e. telegraphs that printed letters and numbers, rather than just sounding Morse dots and dashes. The idea was very old – “House’s Printing Telegraph” was patented in 1848. The original idea was that instead of trained operators using Morse code, a printing telegraph would be faster and could use cheaper staff that only had to know how to read and type. But it took decades before the technology could be perfected so that in long range telegraphy it matched the speed and accuracy of skilled operators using Morse code. However, for specialized uses like stock quotes the technology was generally adequate, although sometimes a little slow. One complaint during the Stock Crash of 1929 was that the tickers ran hours late, so people no longer had a clear idea of what the current prices were.
How were the quotes transmitted?
Pretty much like the quotes you see at the bottom of the cable financial news channels today, generally on a narrow strip of paper.
How/from where were those transmissions sent?
Local offices near the exchange floor got the quotes and retransmitted them to their subscribers.
How did the machines receive transmissions? How did they convert the transmissions into printed quotes?
There were a zillion different patents, but most used a system of synchonized clockwork to type the correct keys in response to the transmitted electrical signals. Most didn’t use Morse code, but special sequences designed to operate their individual machines.
According to Fotos, the ticker tape machine didn’t really change much from their creation until personal computers put them into museums.
I’ve seen ticker tape - it’s about 3/4" wide and comes on a spool like ribbon. Some of the used tape I’ve seen has numbers and letters like on the scroll on CNN or FNN.
Only one company still makes ticker tape, and that’s mostly for parades in NYC.
I can follow the reasoning with how the stock ticker worked. One “master” (input) device at the transmitting end could have many slave (output) devices at receiving ends. But now regarding the telegraph, I follow the explanation of solenoids, but did a telegraph go out to all end-users - like a bulletin? Or, was there a way to send a more personalized message by telegraph to only select users? I WAG it was only for bulletins?
Oh, we’d be so lost if we were sent back a past era!
For commercial telegrams, the practice differered for different situations. In the larger offices there were multiple lines between cities, so operators often had set schedule when they plugged their equipment into the proper switchboard connection, and communicated to a distant operator over a private line. However, overnight news transmissions were set up so that one sender was heard simultaneously over dedicated lines that ran to multiple cities.
In smaller offices, say along a train line, only a single shared line was often used. In this case all of the offices could hear all of the traffic going over the line, so they weren’t supposed to interupt if there was ongoing communication. When an office wanted to send a message, the operator would wait until the line was clear and then telegraph the name of the office that was the recepient, and the operator there was supposed to respond to the request. A telegram that had to go a long distance would have to be written down and retransmitted along one or more additional lines, until it got to its destination. In some cases, where there was a lot of traffic going to the same city, punch tape would be used to record and retransmit the message at high speed.
wait a minute… everybody and their brother has made that joke about 17 times each here on the SDMB and I’m the one who gets slammed for it? I only want what I am due: my Og-given right to drop an over-used, silly line. No one ever SAID I thought it was clever.
