[philo]

I'm reading the auto biography of Lee deForest written in 1950 and he
often talks about how things were back in the "old days".


He mentioned a Wig Wag transmitter but did not describe it.


Earlier in the book he mentioned how the transmitters had the telegraph
key wired to the tuning coil and the transmission would occur at one
frequency and an idle carrier wave would remain at another.

Is that what He meant by wigwag?



Interesting side note:

Though he invented the triode and recognized at once it's value, there
was no where in the book where he gave a cogent explanation of how it
actually worked.

[Scott Dorsey]

In article , philo wrote:
I'm reading the auto biography of Lee deForest written in 1950 and he
often talks about how things were back in the "old days".

He mentioned a Wig Wag transmitter but did not describe it.

It's another name for a "bug" key or a Vibroplex.

Interesting side note:

Though he invented the triode and recognized at once it's value, there
was no where in the book where he gave a cogent explanation of how it
actually worked.

I think he had some basic idea of how amplification worked (with the
grid attracting or repelling electrons passing by), but he clearly had
absolutely no understanding of how the tube worked as an oscillator or
how regeneration worked. And he certainly never got to the point of
working out a transfer function as a characteristic curve.
--scott

--
"C'est un Nagra. C'est suisse, et tres, tres precis."

[philo]

On 03/27/2016 10:00 AM, Scott Dorsey wrote:
In article , philo wrote:
I'm reading the auto biography of Lee deForest written in 1950 and he
often talks about how things were back in the "old days".

He mentioned a Wig Wag transmitter but did not describe it.

It's another name for a "bug" key or a Vibroplex.



OK...he did not explain.

BTW: Though most of my ham gear is gone, I still have my Vibroplex!

Interesting side note:

Though he invented the triode and recognized at once it's value, there
was no where in the book where he gave a cogent explanation of how it
actually worked.

I think he had some basic idea of how amplification worked (with the
grid attracting or repelling electrons passing by), but he clearly had
absolutely no understanding of how the tube worked as an oscillator or
how regeneration worked. And he certainly never got to the point of
working out a transfer function as a characteristic curve.
--scott



Yep. He used a lot of words but he seemed to be stumbling around. That
said, he was smart enough to realize what the triode could be used for.



The book is well worth reading.

[philo]

Never thought to check there first:



De Forest ruefully noted that under these conditions the only successful
"wireless" communication was done by visual semaphore "wig-wag" flags.

[Hank[_5_]]

In article ,
Scott Dorsey wrote:

Though he invented the triode and recognized at once it's value, there
was no where in the book where he gave a cogent explanation of how it
actually worked.

I think he had some basic idea of how amplification worked (with the
grid attracting or repelling electrons passing by), but he clearly had
absolutely no understanding of how the tube worked as an oscillator or
how regeneration worked. And he certainly never got to the point of
working out a transfer function as a characteristic curve.
--scott

I've always felt that deForest's history was another exercise in
alchemical strangeness. It seems fairly clear that he did not have any
real understanding of why or how his tubes worked, or what they might be
capable of actually doing. Nor did he ever devise any practical
circuitry for using them. A much larger contributor to circuitry was
Armstrong, whose patents were overturned in favor of deForest later
on---generally regarded as a travesty of justice. Development of the
high-vacuum triode with a scientific understanding of what the control
grid was doing to the electron stream---and development of a concomitant
technology for series production of the devices was more an AT&T/Bell
Labs effort. Also, the first major use of these devices was as
telephony repeater amplifiers.

Hank

[philo]

On 03/27/2016 11:49 PM, Hank wrote:
In article ,
Scott Dorsey wrote:

Though he invented the triode and recognized at once it's value, there
was no where in the book where he gave a cogent explanation of how it
actually worked.

I think he had some basic idea of how amplification worked (with the
grid attracting or repelling electrons passing by), but he clearly had
absolutely no understanding of how the tube worked as an oscillator or
how regeneration worked. And he certainly never got to the point of
working out a transfer function as a characteristic curve.
--scott

I've always felt that deForest's history was another exercise in
alchemical strangeness. It seems fairly clear that he did not have any
real understanding of why or how his tubes worked, or what they might be
capable of actually doing. Nor did he ever devise any practical
circuitry for using them. A much larger contributor to circuitry was
Armstrong, whose patents were overturned in favor of deForest later
on---generally regarded as a travesty of justice. Development of the
high-vacuum triode with a scientific understanding of what the control
grid was doing to the electron stream---and development of a concomitant
technology for series production of the devices was more an AT&T/Bell
Labs effort. Also, the first major use of these devices was as
telephony repeater amplifiers.

Hank




And of course superheterodyne and FM...he really knew what he was doing.

[Scott Dorsey]

Hank wrote:
I've always felt that deForest's history was another exercise in
alchemical strangeness. It seems fairly clear that he did not have any
real understanding of why or how his tubes worked, or what they might be
capable of actually doing. Nor did he ever devise any practical
circuitry for using them. A much larger contributor to circuitry was
Armstrong, whose patents were overturned in favor of deForest later
on---generally regarded as a travesty of justice. Development of the
high-vacuum triode with a scientific understanding of what the control
grid was doing to the electron stream---and development of a concomitant
technology for series production of the devices was more an AT&T/Bell
Labs effort. Also, the first major use of these devices was as
telephony repeater amplifiers.

Well, one of the problems is that DeForest was convinced that electron
propagation in the vacuum only took place if there was a small amount of
gas left in the tube. In fact, if you do allow a little gas in there, you
get much higher transconductance but much poorer linearity (the extreme
case being a thyratron where all of the electrons are carried by ionized
gas). Because DeForest never really got the idea of modelling the tube's
transfer function, he was never able to separate out the two mechanisms
and consequently was never able to make consistent devices.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."

[philo]

On 03/28/2016 02:39 PM, Scott Dorsey wrote:

Well, one of the problems is that DeForest was convinced that electron
propagation in the vacuum only took place if there was a small amount of
gas left in the tube. In fact, if you do allow a little gas in there, you
get much higher transconductance but much poorer linearity (the extreme
case being a thyratron where all of the electrons are carried by ionized
gas). Because DeForest never really got the idea of modelling the tube's
transfer function, he was never able to separate out the two mechanisms
and consequently was never able to make consistent devices.
--scott




The more I read his book the more I see he did little more than blunder
around...but the book itself is a very interesting read.

[Hank[_5_]]

In article , philo wrote:
On 03/27/2016 11:49 PM, Hank wrote:

I've always felt that deForest's history was another exercise in
alchemical strangeness. It seems fairly clear that he did not have any
real understanding of why or how his tubes worked, or what they might be
capable of actually doing. Nor did he ever devise any practical
circuitry for using them. A much larger contributor to circuitry was
Armstrong, whose patents were overturned in favor of deForest later
on---generally regarded as a travesty of justice. Development of the
high-vacuum triode with a scientific understanding of what the control
grid was doing to the electron stream---and development of a concomitant
technology for series production of the devices was more an AT&T/Bell
Labs effort. Also, the first major use of these devices was as
telephony repeater amplifiers.

Hank




And of course superheterodyne and FM...he really knew what he was doing.

Armstrong was a major contributor---but whether he actually "invented"
the superhet seems to be in doubt, as there was considerable French work
in frequency conversion during WWI. No question that Armstrong brought
the superhet to the home entertainment market with the RCA Radiolas of
the early 1920's. These were really strange beasts, as they used a
reflex circuit to reduce tube count. Add to that the "catacombs"
construction---a wax-filled can with V99 tube sockets. I had one of
these (a "portable") from 1924 as a teenager, and really went through
fits to get it to work, after melting all the wax out of the catacomb.
That portable had a "loudspeaker" (a headhone-type driver into a horn)
and an extra v99 to drive it.

Armstrong's FM was really his baby. All the theoreticians said it
wouldn't work, but it did. I once worked with an old-timer who'd been
involved in setting up the original NTSC TV standard in 1941. They
purposely put a hook into RCA's condemnation of FM by specifying FM for
TV audio (said he).

Hank

Hank

[Hank[_5_]]

In article ,
Scott Dorsey wrote:
Hank wrote:
I've always felt that deForest's history was another exercise in
alchemical strangeness. It seems fairly clear that he did not have any
real understanding of why or how his tubes worked, or what they might be
capable of actually doing. Nor did he ever devise any practical
circuitry for using them. A much larger contributor to circuitry was
Armstrong, whose patents were overturned in favor of deForest later
on---generally regarded as a travesty of justice. Development of the
high-vacuum triode with a scientific understanding of what the control
grid was doing to the electron stream---and development of a concomitant
technology for series production of the devices was more an AT&T/Bell
Labs effort. Also, the first major use of these devices was as
telephony repeater amplifiers.

Well, one of the problems is that DeForest was convinced that electron
propagation in the vacuum only took place if there was a small amount of
gas left in the tube. In fact, if you do allow a little gas in there, you
get much higher transconductance but much poorer linearity (the extreme
case being a thyratron where all of the electrons are carried by ionized
gas). Because DeForest never really got the idea of modelling the tube's
transfer function, he was never able to separate out the two mechanisms
and consequently was never able to make consistent devices.
--scott

DeForest's misunderstanding of the principles of the Edison effect and
the Fleming valve seems to have been pretty basic. His first attempts
to control current flow were "grids" mounted on the outside of the glass
envelope. And he always seemed to think that what he was controlling
was ionized gas conduction, not electrons emitted from a cathode
element.

There were tons of texts written around 1920 that had some pretty
strange theories about what tubes did inside. As I recall, the first
really good text on radio circuits I encountered was Mary Texanna
Loomis's text from the late 20's. I learned EE basics from her text,
Ghirardi's "Radio Physics Course" from 1932, and Terman's 1937 "Radio
Engineering." One text that baffled me was Zworykin/Morton
"Television," which I got as a present at the end of WWII. No
wonder--the physics were much too advanced for me to understand.
Looking back some years later, I think the best text on vacuum tube
physics was Spangenberg's "Vacuum Tubes." It wasn't published until the
dawn of the transistor era, so never got the play that Terman and some
of the others did.

Hank