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Re: Lee DeForest - was - Off topic, but.... More waveguide

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  • widebandit
    No problem... I just wanted to point out that BTL was on the verge of committing to either the mercury arc as a repeater amplifier, or an improved mechanical
    Message 1 of 17 , Jul 30, 2011
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      No problem...

      I just wanted to point out that BTL was on the verge of committing to either the mercury arc as a repeater amplifier, or an improved mechanical repeater when DeForest walked in the door in 1912...

      That BTL was able to turn DeForest's Audion into a viable transcontinental telephone repeater (in more than enough time for the 1915 San Francisco Panama-Pacific Expo) speaks volumes of their expertise...

      But they had missed the potential of the Audion completely...

      It only took fifteen years after that for H.S. Black to discover negative feedback:

      <http://www.alcatel-lucent.com/bstj/vol13-1934/articles/bstj13-1-1.pdf>

      And another forty-five or so to develop feed-forward, pre-distortion techniqes to the point of allowing 6,000 simultaneous transcontinental conversations on a single AR6A microwave channel:

      <http://www.alcatel-lucent.com/bstj/vol62-1983/articles/bstj62-10-3249.pdf>

      But - in the words of the wicked witch of the west: "These things must be handled delicately..."

      I wonder if DeForest ever thought that maybe a 1% royalty on every tube produced might have been a better deal than selling the patent rights?...

      - waw -

      >
      > So the answer is yes. :)
      > (A body's mass measures its inertia and also whether light or heavy)
      > and
      > I never said the Audion was a BTL invention. I said they figured out how to use it and invented Negaive Feedback which stabilized amplifiers.
      >
      >
      >
      > But, the Audion tube as an amplifier was Lee DeForest's invention - not Bell Labs' - he was kind enough to demonstrate the device to Bell Labs engineers October 30 and 31 1912...
      >
      > This happened while Bell Labs engineers were still trying to get past Denver by fooling around with pair loading, mechanical (carbon) repeaters, mercury arc repeaters, and magnetic amplifiers...
      >
      > Up to this point, Bell Labs engineers knew they needed some type of "inertia-less" repeater, but had no idea as to what form such a repeater would take. Fortunately, they were able to take DeForest's device and run with it...
      >
      > AT&T's initial reaction to Bell Labs engineers was - Why didn't you guys think of this? (The audion had already been used as a telegraph detector.)...
      >
      > To quote Thomas Shaw's "The Conquest of Distance by Wire Telephony" - published in the October 1944 Bell System Technical Journal: "There was, of course, considerable chagrin that these prospects had not been recognized much earlier in the Telephone Company's research work on repeaters, but no time was wasted in attempts to develop alibis."
      >
      > <http://www.alcatel-lucent.com/bstj/>
      >
      > - waw -
      >
      > >
      > > ever read up on the labs guys who came up with their first audio amp.
      > >
      > > The line in the book read something like this, "too much distortion in the speaker to carbon microphone repeater.
      > > Carbon particles were too heavy. Electrons in a vacuum tube are much lighter and thus more easily controlled.
      > > Now thats using your noggin.
      > >
      > Quite fascinating! That was still back in the day when Bell Labs invested a LOT of money in pure research. Somebody had an idea, and they funded the research to see if it led anywhere. Why do you think they had so many inventions? They paid really smart people to be creative and play! It didn't always pan out, but when it did, it sure gave them a huge corporate advantage and pride. Things like the transistor weren't developed by people trapped in cubicles tasked to develop "x" and ONLY "x", like many companies do today. They realized the value in spinoff ideas could be cash cows, and sometimes even change the world as we know it. For 2 more examples, look at the "C" language, and UNIX. The engineering quality and flexibility originally designed in is phenomenal! Like anybody had any idea what a web server was in 1970, yet UNIX derivatives remain the preferred server OS online. Show me any other computing device or software that is still in current and widespread usage after 40+ years, yet is essentially unchanged at its core level since its introduction. It's a VERY short list.
      >
      > Somewhere I once saw a "Bell" publication with a small blurb about Shockley and his team developing a thing called a "transistor", and that it -might- be an interesting invention. I'd love to obtain a copy of it, if anyone knows the document I'm referring to, and where I can get a copy.
      >
      > Mike
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