Edison Tube

M79 · Nov 24, 2012

Thomas Edison might have been able to develop a vacuum tube fifteen to twenty years ahead of OTL with a few nudges in the right direction. Suppose that between 1886 and 1890 Edison manages to perfect a triode vacuum tube (instead of OTL 1908-1915), what would be the results?

Dathi THorfinnsson · Nov 26, 2012

M79 said:
Thomas Edison might have been able to develop a vacuum tube fifteen to twenty years ahead of OTL with a few nudges in the right direction. Suppose that between 1886 and 1890 Edison manages to perfect a triode vacuum tube (instead of OTL 1908-1915), what would be the results?

Oh?

The levels of vacuum you need for a successful electronics tube is a lot nastier than than what you need for a light bulb. It's even nastier than what you need for an Xray tube. What makes you think he would have been able to do it? And why would he even try? He was very into very applied science - engineering (sure, cutting edge, even bleeding edge), rather than basic research.

M79 · Dec 1, 2012

He did try in the 1880s by using light bulbs with extra filaments, plates, and eventually filed a patent for the first electronic device based on this in 1883. This led to the investigation of radio detecting technology and eventually the diode about 1904/1905 by a British scientist. So I think Edison could develop a diode or maybe even a triode in 1890, and if he does will this kick-start the development of electronics by 15-20 years? I also wonder that if vacuum tubes develop earlier does this allow earlier transistors to develop, perhaps before WWII?

Mark E. · Dec 2, 2012

M79 said:
He did try in the 1880s by using light bulbs with extra filaments, plates, and eventually filed a patent for the first electronic device based on this in 1883. This led to the investigation of radio detecting technology and eventually the diode about 1904/1905 by a British scientist. So I think Edison could develop a diode or maybe even a triode in 1890, and if he does will this kick-start the development of electronics by 15-20 years? I also wonder that if vacuum tubes develop earlier does this allow earlier transistors to develop, perhaps before WWII?

Didn't the Germans develop an early transistor in the thirties? They didn't pursue it because vacuum tubes were well established and more reliable.

Dathi THorfinnsson · Dec 3, 2012

Hmmm... The earliest electronic tubes WEREN'T high vacuum. Although, they very soon went high vacuum, and worked rather better that way.

I retract my objection.

Minchandre · Dec 3, 2012

Mark E. said:
Didn't the Germans develop an early transistor in the thirties? They didn't pursue it because vacuum tubes were well established and more reliable.

Not particularly. There was a single guy - something Heil - that worked on it in the early 30s, but abandoned the idea before developing it at all to help with more immediately applicable things during the war.

Also, with regards to Edison - he played with tubes as early as the 1880s, but his lack of a proper physics education severely handicapped him. It's unlikely that he would have been able to develop his ideas, except by sheer coincidence.

There's also issues with trying to develop tubes as anything aside from diodes before the discovery of the electron in 1897; and even as diodes, without the idea of a charge-carrying particle, it's kind of weird to make the leap from "a hot piece of metal in vacuum becomes increasingly positive" to "I bet we could channel electrical signals through such a device, but only in one direction!"

M79 · Dec 3, 2012

There was Hiel along with a Russian and another American I think, any of the three (or maybe two?) could have made a remarkable discovery. And given that Edison might have gotten lucky, even if the tube is built does not mean its significance is recognized right away. Edison has the knack for applications so I figured if he could discover it...

M79 · Jan 27, 2013

(bump to jump-start thread)

gregxgraves · Feb 10, 2013

Both Lee De Forest and Robert von Lieben worked with electronic valves (tubes) but based on my understanding, they were limited by the difficulty in evacuating the tube - although in De Forest's case, he thought that it was necessary to function.

1906 - De Forest patents the Audion, limited by his insistence that the trace mercury vapor left by the vacuum process is necessary for it to function. von Lieben patents his own amplifier (need to find more sources on this that aren't in German!)

1913 - Irving Langmuir develops the diffusion pump that allows more of the mercury vapor to be removed from the tube and this helps make the tubes more reliable.

Argh, this is a good question! I'm digging through more sources, but I wanted to get at least a baseline out there.

phx1138 · Feb 16, 2013

Does it have to be Edison?

There were quite a few people working on improving lightbulbs. So suppose it's (say) Swan, who IIRC was an actual physicist. And suppose the objective isn't a diode or triode, but a brighter bulb? Or a variable-brightness bulb (what we'd call a tri-light)?

The investigator doesn't actually have to know why the thing works to see interesting results... Recall Roentgen & x-rays.