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Forgotten History: The origin of TDD
Posted: Thu Nov 26, 2009 2:45 pm
by seamusTX
For nearly a century after the invention of the telephone, it was useless to people who were deaf or unable to speak.
In 1964, Dr. James Marsters, a deaf orthodontist in southern California, teamed up with a Stanford University physicist, Robert Weitbrecht, and an electrical engineer, Andrew Saks, to figure out how to use surplus Teletype machines over regular telephone lines. The obsolete Teletypes were cheap or free.
At the time, Ma Bell prohibited connection of any device other than their rented phones to the telephone network (pirate extension phones used to be a garage industry). The two men used an acoustic coupler to connect Teletypes to conventional phones. You younger folk would never have seen one of these things outside a museum. You can see one in the movie
War Games.
The acoustic coupler did not violate AT&T's rules, but the company mulishly tried to prohibit them until a federal court told them otherwise.
The prototypes evolved into Telecommunication Devices for the Deaf (TDD), which later were manufactured with more modern technology like LED and liquid crystal displays.
As far as I know, none of the originators made any profit from their invention.
Eventually, tens of thousands of deaf Americans used these devices, and most government agencies and companies had TDD numbers. E-mail and other forms of electronic communication have nearly wiped them out.
Dr. Marsters died in August at age 85.
http://en.wikipedia.org/wiki/Telecommun ... r_the_deaf" onclick="window.open(this.href);return false;
- Jim
Re: Forgotten History: The origin of TDD
Posted: Thu Nov 26, 2009 4:11 pm
by jimlongley
As a telephone man, teletype man, and ham, I used to actively participate in the program (sponsired by ma bell, by the way) fixing up and supplying old teletype equipment as TTDs.
Ma bell's rules did not prohibit attaching the device to the line, it required an interface which was somewhat expensive, about $100.00 for installation and then a monthly charge. The Carterphone I decision was not brought by anyone having to do with TTD, but by a company that wanted to attach phone patches and answering machines to the line and FCC declared that they could do so but needed an interface. This did open the door for other devices to be attached to the network directly, albeit with an interface.
Since then there have been several other decisions, one known as Carterphone II esentially eliminated the need for the interface for modems, answering machines, and other stuff, as long as it passed FCC type acceptance trials. Several manufacturers were caught marketing stuff that was not the same as what they submitted for type acceptance.
Extension phones were a whole different thing, Ma Bell was able to make a case that unlike answering machines and TDDs, phones needed to meet very strict standards in order to communicate effectively and not cause interference. Eventually customer owned extensions and then totally customer owned premesis equipment became the rule, but that was not without some major headaches. I had a customer issue that I worked on for weeks, with the customer eventually complaining to the regulatory authority (PUC in Texas) and the FCC.
I was able, with specialised test equipment, to prove beyond any doubt, that the interference that the customer was experiencing, from CB, baby monitors, and a local ham (who they were blaming it all on) was a product of the poor quality telephones they had equipped themselves with. Last I heard they were going to sue the FCC, PUC, telephone company, and me personally, for incompetence, conspiracy, and a bunch of other stuff. Nothing in the 18 years since.
Re: Forgotten History: The origin of TDD
Posted: Thu Nov 26, 2009 4:43 pm
by seamusTX
EMI or RFI was a big problem with the state of the art in the 1960s and 70s.
AT&T was a great innovator in some ways. They paid the salaries and furnished labs of the inventors of the transistor (John Bardeen, William Shockley, and Walter Brattain), which literally changed the world on the order of the steam engine or the assembly line. Their electronic switches were among the most advanced (though invisible) computers of the time.
However, they were not so good with consumer appliances. Did they produce an answering machine before Judge Greene's fateful decision?
It's quite remarkable how you can now buy a dozen items at Radio Shack that plug directly into the phone network without bringing Western Civilization to its knees, and you don't need an engineering degree.
- Jim
Re: Forgotten History: The origin of TDD
Posted: Thu Nov 26, 2009 6:31 pm
by jimlongley
My father worked at Bell Labs when I was a kid and knew "the three" as well as Claude Shannon, who he also knew when they were grad students at MIT together. I had the dubious privilege of meeting Shannon when I was a kid, I was not real interested, and then, many years later, when I was teaching technical courses at Bellcore in Lisle, IL I was really privileged to carry on a short correspondence with Shannon when I asked his permission to use some of his work in my training.
My father, who literally forced me to get a ham license when I was nine, taught me about transistors before they became a haoushold word, and of course I got in dutch with a teacher at school, about 1955 or 56, by telling him and classmates about this new technology, and the teacher scoffed at me saying there was no way that silicon could conduct electricity, much less switch on and off. This was in a discussion about model airplanes and the possibilities of radio control.
Re: Forgotten History: The origin of TDD
Posted: Thu Nov 26, 2009 7:34 pm
by seamusTX
jimlongley wrote:I had the dubious privilege of meeting Shannon when I was a kid, I was not real interested, and then, many years later, when I was teaching technical courses at Bellcore in Lisle, IL...
What was dubious about meeting Dr. Shannon? He is right up there with Einstein, though not as well known.
I visited the Bell Labs facility in Lisle when I was in high school, probably around 1974 or 75. They let us use their computer named RAX.
- Jim
Re: Forgotten History: The origin of TDD
Posted: Thu Nov 26, 2009 7:57 pm
by jimlongley
seamusTX wrote:jimlongley wrote:I had the dubious privilege of meeting Shannon when I was a kid, I was not real interested, and then, many years later, when I was teaching technical courses at Bellcore in Lisle, IL...
What was dubious about meeting Dr. Shannon? He is right up there with Einstein, though not as well known.
I visited the Bell Labs facility in Lisle when I was in high school, probably around 1974 or 75. They let us use their computer named RAX.
- Jim
I was seven or eight years old, my mother had driven us to New Jersey to see my father, and then we went into NY City to see a play. I was sick, a cold or something, and supremely bored, and was not at all interested.
My father was at Bell Labs for three or four years and we kept our home near Albany, so he came home on weekends, or my mother went to visit him. I went on the visits only rarely, not a great trip in the days when the fastest road was 9W. My mother smoked like a chimney and it made me carsick.
Re: Forgotten History: The origin of TDD
Posted: Thu Nov 26, 2009 8:34 pm
by seamusTX
I guess at age 8 Shannon's accomplishments would not mean much, even it you weren't ill.
- Jim
Re: Forgotten History: The origin of TDD
Posted: Thu Nov 26, 2009 9:41 pm
by jimlongley
Yeah, we left Bell Labs and went over to Manhattan, checked into a hotel and went to see "Peter Pan" By that time the fever was getting pretty intense, I was nauseated, and flatulent in the extreme - we left the play early and my mother never forgave me. I had a joyous childhood.
Re: Forgotten History: The origin of TDD
Posted: Thu Nov 26, 2009 11:55 pm
by Oldgringo
seamusTX wrote:
I visited the Bell Labs facility in Lisle when I was in high school, probably around 1974 or 75.
Speaking of forgotten history, didn't Saigon fall in April of '75?
Re: Forgotten History: The origin of TDD
Posted: Fri Nov 27, 2009 8:14 am
by seamusTX
Yeah. I don't think anyone who was alive and not zonked out on drugs has forgetten it.
- Jim
Re: Forgotten History: The origin of TDD
Posted: Fri Nov 27, 2009 8:52 am
by seamusTX
I wrote:I visited the Bell Labs facility in Lisle when I was in high school, probably around 1974 or 75.
Wow! I ate too much turkey or something yesterday. I was in high school 1969-73. The Bell Labs visit was in my first or second year.
- Jim