The Energy Saver Vacuum Tube of the Future

[John Larkin]

On Tue, 14 May 2019 01:11:37 -0400, bitrex <user@example.net> wrote:

On 5/14/19 12:08 AM, John Larkin wrote:
On Mon, 13 May 2019 23:40:59 -0400, bitrex <user@example.net> wrote:

On 5/13/19 11:23 PM, Unlisted wrote:
In the past, vacuum tubes required a lot of electricity to operate. Most
of that electricity was used to heat the heating wire, known as the
filament, which is very similar to the filament in an incandescent light
bulb. All heated wire filaments whether inside of lightbulbs or vacuum
tubes are now obsolete. They have been replaced by more efficient
florescent bulbs, or the most efficient LED bulbs.

However, you can not use a LED as a filament inside a vacuum tube. It
would appear to illuminate a tube and look like a filament, but it would
not provide the heat needed to heat the tube's cathode and thus it will
not provide the electron movement which makes the tube do it's job.

The solution is simple. Provide a hollow cylinder inside the tube's
cathode, where the filament once existed. The user of the tube must
place a lit wax candle inside the tube's special cathode. The heat from
the candle replaces the electric filament, which makes the tube work as
it did before, but with much less electricity.

But it dont stop there. So far you're only using the heat from the
candle, while the light from the flame is wasted. Therefore, the tube
needs a solar cell inside it's housing, near the candle's flame. That
solar cell produces electricity from the light of the flame. That
electricity is then used to power the circuit.

But it gets even better, by placing a transistor between the vacuum
tube's cathode, grids, and plate. The flow of free electrons will
bombard the transistor. That will make the transistor produce between 6
and up to 20 times more power than a transistor on a circuit board,
because of the added electrons. Add more transistors inside that tube
and you will achieve maximum power. That power combined with the tube's
power will turn a vacuum tube, which once produced a maximum of (example
20 watts audio output), into a tube now capable of producing 350 up to
800 watts RMS audio power.

"watts RMS"

TRIGGERED

Different from watts peak. Nothing wrong with that.

The OP is clumsy and not very funny, but there have been attempts at
non-thermionic tubes. It's a very appealing idea, but none of the
cathodes have lasted. Microtips work for a while, but basicly sputter
themselves to death. Ditto carbon nanotubes.



There were a few patents for cold-cathode gas tube linear amplifiers in
the Fifties, designed to use a glow discharge as a source of electrons
to modulate. Weird tubes with two cathodes both designed to be negative
with respect to the control electrode.

Not sure if any were ever actually made for sale, maybe if transistors
hadn't worked out. They'd still draw gobs of "plate" power as compared
to transistors so limited applications, maybe in high-reliability high G
force applications that would break a traditional filament or control grid

Transistors have heat sinks because they draw gobs of collector power.

Adding a small vacuum gap between gate and drain would turn a 50 volt
mosfet into a 50 kilovolt mosfet. Sort of a pin diode effect, add some
insulation to get more voltage.

There have also been ideas of electron-launching schottky diode
structures.

I invented a scanning electron microscope cathode based on a
possibly-tapered optical fiber with a transparent photocathode plated
on the end. The numbers looked OK. You want SEM cathodes to be very
small, so a single-mode fiber is about right. The people that I was
working with were enthusiastic about building a cheap SEM, but got
diverted to other stuff.

A sem could be insanely cheap; the vacuum pump is expensive.


--

John Larkin Highland Technology, Inc

lunatic fringe electronics

 

On Tuesday, 14 May 2019 14:04:34 UTC+1, Martin Brown wrote:

On 14/05/2019 10:11, Jeroen Belleman wrote:
upsidedown@downunder.com wrote:
On Tue, 14 May 2019 01:53:06 -0400, bitrex <user@example.net> wrote:

On 5/14/19 1:23 AM, Banders wrote:
On 05/13/2019 08:23 PM, Unlisted wrote:
All heated wire filaments whether inside of lightbulbs or vacuum
tubes are now obsolete. They have been replaced by more efficient
florescent bulbs, or the most efficient LED bulbs.
That might turn around. 3 year-old story...

https://www.britishgas.co.uk/business/blog/the-return-of-the-incandescent-light-bulb/


One of those MIT blurbs again

While the idea of reflecting back the useless IR radiation into the
filament is good, but unfortunately tungsten nor any other solid
material can't handle much above 2700 K temperatures.If we had such
materials, we could use electric current as well to reach higher
temperatures.


This cannot possibly be an original idea and there's probably
a good reason why it isn't done. Maybe it's too expensive to be
worth the trouble, or the heat or the evaporation of the filament
spoils the filter in short order, or maybe something else yet.

It is routinely done in SOX low pressure sodium lamps to reflect back an
unwanted near infrared emission line and so allow the sodium vapour to
remain warmer with less input power and force it to emit in the wanted
visible band. It also speeds up the warm up period red neon glow phase.

ISTR they put a thin InO layer on the inside of the outer envelope.

http://lamptech.co.uk/Documents/SO%20Introduction.htm

I came across a 1974 patent application of the idea, and I'm sure
it wasn't novel even then.

done with halogens too. The gain is nothing like the OP claims.


NT

 

[Jeroen Belleman]

tabbypurr@gmail.com wrote:

On Tuesday, 14 May 2019 14:04:34 UTC+1, Martin Brown wrote:
On 14/05/2019 10:11, Jeroen Belleman wrote:
upsidedown@downunder.com wrote:
On Tue, 14 May 2019 01:53:06 -0400, bitrex <user@example.net> wrote:

On 5/14/19 1:23 AM, Banders wrote:
On 05/13/2019 08:23 PM, Unlisted wrote:
All heated wire filaments whether inside of lightbulbs or vacuum
tubes are now obsolete. They have been replaced by more efficient
florescent bulbs, or the most efficient LED bulbs.
That might turn around. 3 year-old story...

https://www.britishgas.co.uk/business/blog/the-return-of-the-incandescent-light-bulb/

One of those MIT blurbs again

While the idea of reflecting back the useless IR radiation into the
filament is good, [...]

done with halogens too. The gain is nothing like the OP claims.


NT

Halogen lamps have no IR mirror to my knowledge. It's a clean
fused quartz bulb. They have higher efficiency because they are
run hotter than ordinary lamps, which is made possible by the
addition of a little of some halogen inside. This keeps the bulb
clear and extends the lifetime of the filament.

Jeroen Belleman

 

[bitrex]

On 5/14/19 6:07 AM, DecadentLinuxUserNumeroUno@decadence.org wrote:

upsidedown@downunder.com wrote in
newspskdetnt8akhq8qrote7nf8abkqbjjlmf@4ax.com:

millions of years of human evolution.

Did not know that we were around that long.

I've only been around since 1979, myself.

 

[Phil Hobbs]

On 5/14/19 5:11 AM, Jeroen Belleman wrote:

upsidedown@downunder.com wrote:
On Tue, 14 May 2019 01:53:06 -0400, bitrex <user@example.net> wrote:

On 5/14/19 1:23 AM, Banders wrote:
On 05/13/2019 08:23 PM, Unlisted wrote:
All heated wire filaments whether inside of lightbulbs or vacuum
tubes are now obsolete. They have been replaced by more efficient
florescent bulbs, or the most efficient LED bulbs.
That might turn around. 3 year-old story...

https://www.britishgas.co.uk/business/blog/the-return-of-the-incandescent-light-bulb/


One of those MIT blurbs again

While the idea of reflecting back the useless IR radiation into the
filament is good, but unfortunately tungsten nor any other solid
material can't handle much above 2700 K temperatures.If we had such
materials, we could use electric current as well to reach higher
temperatures.


This cannot possibly be an original idea and there's probably
a good reason why it isn't done. Maybe it's too expensive to be
worth the trouble, or the heat or the evaporation of the filament
spoils the filter in short order, or maybe something else yet.

I came across a 1974 patent application of the idea, and I'm sure
it wasn't novel even then.

Jeroen Belleman

Causes gross hotspots on the filament if it's focused back, and doesn't
work well if it isn't, because loss in the coating eventually dissipates
most of the heat before it can be reabsorbed by the filament.

Cheers

Phil Hobbs

--
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC
Optics, Electro-optics, Photonics, Analog Electronics

160 North State Road #203
Briarcliff Manor NY 10510

hobbs at electrooptical dot net
http://electrooptical.net

 

[bitrex]

On 5/14/19 2:59 AM, Owen Cook wrote:

Different from watts peak. Nothing wrong with that.

The OP is clumsy and not very funny, but there have been attempts at
non-thermionic tubes. It's a very appealing idea, but none of the
cathodes have lasted. Microtips work for a while, but basicly sputter
themselves to death. Ditto carbon nanotubes.


About 50 odd years ago, a military manpack radio, PRC-25, had a radio active valve as the final. I believed at the time that the radioactivity provided the electron flow, rather than a heater, kind of a battery saving technique.

There were special disposal instructions for these valves, but I am not sure the instructions were followed all the time. My guess there are a lot of radioactive dumps in Vietnam and other places.

Yeah, like the United States

Owen

 

Bill Sloman <bill.sloman@ieee.org> wrote in
news:2ff7c188-158b-4ab2-a1b2-750d756c55e2@googlegroups.com:

The visual system which we share with the rest of great apes
probably settled down earlier than that - most of us have
three-colour vision - which would make it more than 20 million
years old.

He said human evolution not eye evolution.

He said human evolution, not pre-human ancestor.

And I KNEW this shit would start.

 

upsidedown@downunder.com wrote in
news:faelde9i7ch97i7eliq9lhbm7qggs77i12@4ax.com:

On Tue, 14 May 2019 10:07:28 +0000 (UTC),
DecadentLinuxUserNumeroUno@decadence.org wrote:

upsidedown@downunder.com wrote in
newspskdetnt8akhq8qrote7nf8abkqbjjlmf@4ax.com:

millions of years of human evolution.

Did not know that we were around that long.

I am not a Creationist.

Neither am I, dingledorf.

Dinosaurs yes... been here way back when. Us... NO you fucking
idiot.

Evolved or created does not matter, we simply have not been here
on this big blue ball for "millions of years".

And were we created, that creator did not need millions of years
of evolution to give us our DNA as he left us here to mentally
evolve with those few tens or even a couple or few hundreds of
thousands of years ago. But not millions. Not us here or us in the
creation lab. Did not take that long.

Spectral acclimation takes even less time. Just ask a Morlock.

<https://en.wikipedia.org/wiki/Morlock>

 

[bitrex]

On 5/14/19 11:26 AM, Phil Hobbs wrote:

On 5/14/19 5:11 AM, Jeroen Belleman wrote:
upsidedown@downunder.com wrote:
On Tue, 14 May 2019 01:53:06 -0400, bitrex <user@example.net> wrote:

On 5/14/19 1:23 AM, Banders wrote:
On 05/13/2019 08:23 PM, Unlisted wrote:
All heated wire filaments whether inside of lightbulbs or vacuum
tubes are now obsolete. They have been replaced by more efficient
florescent bulbs, or the most efficient LED bulbs.
That might turn around. 3 year-old story...

https://www.britishgas.co.uk/business/blog/the-return-of-the-incandescent-light-bulb/



One of those MIT blurbs again

While the idea of reflecting back the useless IR radiation into the
filament is good, but unfortunately tungsten nor any other solid
material can't handle much above 2700 K temperatures.If we had such
materials, we could use electric current as well to reach higher
temperatures.


This cannot possibly be an original idea and there's probably
a good reason why it isn't done. Maybe it's too expensive to be
worth the trouble, or the heat or the evaporation of the filament
spoils the filter in short order, or maybe something else yet.

I came across a 1974 patent application of the idea, and I'm sure
it wasn't novel even then.

Jeroen Belleman

Causes gross hotspots on the filament if it's focused back, and doesn't
work well if it isn't, because loss in the coating eventually dissipates
most of the heat before it can be reabsorbed by the filament.

Cheers

Phil Hobbs

I wonder if a team of materials science PhDs and professors from MIT and
Purdue have thought about any of that stuff

 

On Tuesday, 14 May 2019 15:20:20 UTC+1, Jeroen Belleman wrote:

tabbypurr wrote:
On Tuesday, 14 May 2019 14:04:34 UTC+1, Martin Brown wrote:
On 14/05/2019 10:11, Jeroen Belleman wrote:
upsidedown@downunder.com wrote:
On Tue, 14 May 2019 01:53:06 -0400, bitrex <user@example.net> wrote:
On 5/14/19 1:23 AM, Banders wrote:
On 05/13/2019 08:23 PM, Unlisted wrote:

All heated wire filaments whether inside of lightbulbs or vacuum
tubes are now obsolete. They have been replaced by more efficient
florescent bulbs, or the most efficient LED bulbs.
That might turn around. 3 year-old story...

https://www.britishgas.co.uk/business/blog/the-return-of-the-incandescent-light-bulb/

One of those MIT blurbs again

While the idea of reflecting back the useless IR radiation into the
filament is good, [...]


done with halogens too. The gain is nothing like the OP claims.


NT

Halogen lamps have no IR mirror to my knowledge.

Many do.
eg
http://www.lighting.philips.com/main/prof/conventional-lamps-and-tubes/halogen-lamps/lv-halogen-with-reflector/energy-advantage-ir-mr16

NT

It's a clean
fused quartz bulb. They have higher efficiency because they are
run hotter than ordinary lamps, which is made possible by the
addition of a little of some halogen inside. This keeps the bulb
clear and extends the lifetime of the filament.

Jeroen Belleman

basic stuff.

 

On Tuesday, 14 May 2019 16:26:57 UTC+1, Phil Hobbs wrote:

On 5/14/19 5:11 AM, Jeroen Belleman wrote:
upsidedown@downunder.com wrote:
On Tue, 14 May 2019 01:53:06 -0400, bitrex <user@example.net> wrote:

On 5/14/19 1:23 AM, Banders wrote:
On 05/13/2019 08:23 PM, Unlisted wrote:
All heated wire filaments whether inside of lightbulbs or vacuum
tubes are now obsolete. They have been replaced by more efficient
florescent bulbs, or the most efficient LED bulbs.
That might turn around. 3 year-old story...

https://www.britishgas.co.uk/business/blog/the-return-of-the-incandescent-light-bulb/


One of those MIT blurbs again

While the idea of reflecting back the useless IR radiation into the
filament is good, but unfortunately tungsten nor any other solid
material can't handle much above 2700 K temperatures.If we had such
materials, we could use electric current as well to reach higher
temperatures.


This cannot possibly be an original idea and there's probably
a good reason why it isn't done. Maybe it's too expensive to be
worth the trouble, or the heat or the evaporation of the filament
spoils the filter in short order, or maybe something else yet.

I came across a 1974 patent application of the idea, and I'm sure
it wasn't novel even then.

Jeroen Belleman

Causes gross hotspots on the filament if it's focused back, and doesn't
work well if it isn't, because loss in the coating eventually dissipates
most of the heat before it can be reabsorbed by the filament.

Cheers

Phil Hobbs

Well that sounds solvable - metal coat the envelope


NT

 

[Dimitrij Klingbeil]

On 2019-05-14 17:26, Phil Hobbs wrote:

On 5/14/19 5:11 AM, Jeroen Belleman wrote:
upsidedown@downunder.com wrote:
On Tue, 14 May 2019 01:53:06 -0400, bitrex <user@example.net
wrote:

On 5/14/19 1:23 AM, Banders wrote:
On 05/13/2019 08:23 PM, Unlisted wrote:
All heated wire filaments whether inside of lightbulbs or
vacuum tubes are now obsolete. They have been replaced by
more efficient florescent bulbs, or the most efficient LED
bulbs.
That might turn around. 3 year-old story...

https://www.britishgas.co.uk/business/blog/the-return-of-the-incandescent-light-bulb/




One of those MIT blurbs again

While the idea of reflecting back the useless IR radiation into
the filament is good, but unfortunately tungsten nor any other
solid material can't handle much above 2700 K temperatures.If we
had such materials, we could use electric current as well to
reach higher temperatures.


This cannot possibly be an original idea and there's probably a
good reason why it isn't done. Maybe it's too expensive to be worth
the trouble, or the heat or the evaporation of the filament spoils
the filter in short order, or maybe something else yet.

I came across a 1974 patent application of the idea, and I'm sure
it wasn't novel even then.

Jeroen Belleman

Causes gross hotspots on the filament if it's focused back, and
doesn't work well if it isn't, because loss in the coating eventually
dissipates most of the heat before it can be reabsorbed by the
filament.

Looks like it's been tried a while (nearly 40 years) ago:

<http://www.lamptech.co.uk/Spec%20Sheets/IN%20WC%20DuroTest%20120-65G30IRC-E26.htm>

Again, developed in cooperation with the MIT

 

[bitrex]

On 5/14/19 6:16 PM, tabbypurr@gmail.com wrote:

On Tuesday, 14 May 2019 16:26:57 UTC+1, Phil Hobbs wrote:
On 5/14/19 5:11 AM, Jeroen Belleman wrote:
upsidedown@downunder.com wrote:
On Tue, 14 May 2019 01:53:06 -0400, bitrex <user@example.net> wrote:

On 5/14/19 1:23 AM, Banders wrote:
On 05/13/2019 08:23 PM, Unlisted wrote:
All heated wire filaments whether inside of lightbulbs or vacuum
tubes are now obsolete. They have been replaced by more efficient
florescent bulbs, or the most efficient LED bulbs.
That might turn around. 3 year-old story...

https://www.britishgas.co.uk/business/blog/the-return-of-the-incandescent-light-bulb/


One of those MIT blurbs again

While the idea of reflecting back the useless IR radiation into the
filament is good, but unfortunately tungsten nor any other solid
material can't handle much above 2700 K temperatures.If we had such
materials, we could use electric current as well to reach higher
temperatures.


This cannot possibly be an original idea and there's probably
a good reason why it isn't done. Maybe it's too expensive to be
worth the trouble, or the heat or the evaporation of the filament
spoils the filter in short order, or maybe something else yet.

I came across a 1974 patent application of the idea, and I'm sure
it wasn't novel even then.

Jeroen Belleman

Causes gross hotspots on the filament if it's focused back, and doesn't
work well if it isn't, because loss in the coating eventually dissipates
most of the heat before it can be reabsorbed by the filament.

Cheers

Phil Hobbs

Well that sounds solvable - metal coat the envelope


NT

Aha a perfect reflector is also a perfect insulator so you get excellent
efficiency that way. it's GENIUS. get dis guy a phd

 

[John Larkin]

On Mon, 13 May 2019 23:59:55 -0700 (PDT), Owen Cook <xemoth@gmail.com>
wrote:

On Tuesday, May 14, 2019 at 2:08:12 PM UTC+10, John Larkin wrote:
On Mon, 13 May 2019 23:40:59 -0400, bitrex <user@example.net> wrote:

On 5/13/19 11:23 PM, Unlisted wrote:
In the past, vacuum tubes required a lot of electricity to operate. Most
of that electricity was used to heat the heating wire, known as the
filament, which is very similar to the filament in an incandescent light
bulb. All heated wire filaments whether inside of lightbulbs or vacuum
tubes are now obsolete. They have been replaced by more efficient
florescent bulbs, or the most efficient LED bulbs.

However, you can not use a LED as a filament inside a vacuum tube. It
would appear to illuminate a tube and look like a filament, but it would
not provide the heat needed to heat the tube's cathode and thus it will
not provide the electron movement which makes the tube do it's job.

The solution is simple. Provide a hollow cylinder inside the tube's
cathode, where the filament once existed. The user of the tube must
place a lit wax candle inside the tube's special cathode. The heat from
the candle replaces the electric filament, which makes the tube work as
it did before, but with much less electricity.

But it dont stop there. So far you're only using the heat from the
candle, while the light from the flame is wasted. Therefore, the tube
needs a solar cell inside it's housing, near the candle's flame. That
solar cell produces electricity from the light of the flame. That
electricity is then used to power the circuit.

But it gets even better, by placing a transistor between the vacuum
tube's cathode, grids, and plate. The flow of free electrons will
bombard the transistor. That will make the transistor produce between 6
and up to 20 times more power than a transistor on a circuit board,
because of the added electrons. Add more transistors inside that tube
and you will achieve maximum power. That power combined with the tube's
power will turn a vacuum tube, which once produced a maximum of (example
20 watts audio output), into a tube now capable of producing 350 up to
800 watts RMS audio power.

"watts RMS"

TRIGGERED

Different from watts peak. Nothing wrong with that.

The OP is clumsy and not very funny, but there have been attempts at
non-thermionic tubes. It's a very appealing idea, but none of the
cathodes have lasted. Microtips work for a while, but basicly sputter
themselves to death. Ditto carbon nanotubes.


About 50 odd years ago, a military manpack radio, PRC-25, had a radio active valve as the final. I believed at the time that the radioactivity provided the electron flow, rather than a heater, kind of a battery saving technique.

Some thyratrons had a bit of radioactive gas inside to make ions, to
reduce trigger jitter.

This is my Krytron:

https://www.dropbox.com/s/i2hhyvouro59c6l/Kry_Guts.jpg?dl=0

https://www.dropbox.com/s/7vkdemdk48k3myd/Kry_Danger.jpg?dl=0

That little thing will switch megawatts.


--

John Larkin Highland Technology, Inc
picosecond timing precision measurement

jlarkin att highlandtechnology dott com
http://www.highlandtechnology.com

 

[Jan Panteltje]

On a sunny day (Wed, 15 May 2019 00:23:37 +0200) it happened Dimitrij
Klingbeil <nospam@no-address.com> wrote in <qbff5f$ctq$1@dont-email.me>:

Looks like it's been tried a while (nearly 40 years) ago:

http://www.lamptech.co.uk/Spec%20Sheets/IN%20WC%20DuroTest%20120-65G30IRC-E26.htm

Again, developed in cooperation with the MIT

Nice idea, how 'bout 'carbon nano nano tubes', seems to be the solution for everything these days, as heater?
Very strong?
Edison used carbon in his first bulbs IIRC.

?

 

[Phil Hobbs]

On 5/14/19 10:14 AM, John Larkin wrote:

On Tue, 14 May 2019 01:11:37 -0400, bitrex <user@example.net> wrote:

On 5/14/19 12:08 AM, John Larkin wrote:
On Mon, 13 May 2019 23:40:59 -0400, bitrex <user@example.net
wrote:

On 5/13/19 11:23 PM, Unlisted wrote:
In the past, vacuum tubes required a lot of electricity to
operate. Most of that electricity was used to heat the
heating wire, known as the filament, which is very similar to
the filament in an incandescent light bulb. All heated wire
filaments whether inside of lightbulbs or vacuum tubes are
now obsolete. They have been replaced by more efficient
florescent bulbs, or the most efficient LED bulbs.

However, you can not use a LED as a filament inside a vacuum
tube. It would appear to illuminate a tube and look like a
filament, but it would not provide the heat needed to heat
the tube's cathode and thus it will not provide the electron
movement which makes the tube do it's job.

The solution is simple. Provide a hollow cylinder inside the
tube's cathode, where the filament once existed. The user of
the tube must place a lit wax candle inside the tube's
special cathode. The heat from the candle replaces the
electric filament, which makes the tube work as it did
before, but with much less electricity.

But it dont stop there. So far you're only using the heat
from the candle, while the light from the flame is wasted.
Therefore, the tube needs a solar cell inside it's housing,
near the candle's flame. That solar cell produces electricity
from the light of the flame. That electricity is then used to
power the circuit.

But it gets even better, by placing a transistor between the
vacuum tube's cathode, grids, and plate. The flow of free
electrons will bombard the transistor. That will make the
transistor produce between 6 and up to 20 times more power
than a transistor on a circuit board, because of the added
electrons. Add more transistors inside that tube and you will
achieve maximum power. That power combined with the tube's
power will turn a vacuum tube, which once produced a maximum
of (example 20 watts audio output), into a tube now capable
of producing 350 up to 800 watts RMS audio power.

"watts RMS"

TRIGGERED

Different from watts peak. Nothing wrong with that.

The OP is clumsy and not very funny, but there have been attempts
at non-thermionic tubes. It's a very appealing idea, but none of
the cathodes have lasted. Microtips work for a while, but basicly
sputter themselves to death. Ditto carbon nanotubes.



There were a few patents for cold-cathode gas tube linear
amplifiers in the Fifties, designed to use a glow discharge as a
source of electrons to modulate. Weird tubes with two cathodes both
designed to be negative with respect to the control electrode.

Not sure if any were ever actually made for sale, maybe if
transistors hadn't worked out. They'd still draw gobs of "plate"
power as compared to transistors so limited applications, maybe in
high-reliability high G force applications that would break a
traditional filament or control grid

Transistors have heat sinks because they draw gobs of collector
power.

Adding a small vacuum gap between gate and drain would turn a 50
volt mosfet into a 50 kilovolt mosfet.

Except for the resulting hot carrier damage. All that energy has to go
someplace.

Sort of a pin diode effect, add some insulation to get more voltage.

There have also been ideas of electron-launching schottky diode
structures.

I invented a scanning electron microscope cathode based on a
possibly-tapered optical fiber with a transparent photocathode
plated on the end. The numbers looked OK. You want SEM cathodes to be
very small, so a single-mode fiber is about right. The people that I
was working with were enthusiastic about building a cheap SEM, but
got diverted to other stuff.

Replacement cathodes are around $1k--see e.g.

https://www.microtonano.com/Denka-M-3-LaB6-EM-cathodes.php#a14AE3301B

> A sem could be insanely cheap; the vacuum pump is expensive.

And so is the stage, and the electron optics, and the scan coils, and
the focusing coils, and so on. High resolution SEMs require a lot of
high-precision vacuum mechanics and magnetics. The cathode isn't the
expensive part.

Running the yoke into the sample can cause some thousands of dollars'
worth of damage. (Ask me how I know.)

Cheers

Phil Hobbs

--
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC / Hobbs ElectroOptics
Optics, Electro-optics, Photonics, Analog Electronics
Briarcliff Manor NY 10510

http://electrooptical.net
http://hobbs-eo.com

 

[Phil Hobbs]

On 5/14/19 4:42 AM, upsidedown@downunder.com wrote:

On Tue, 14 May 2019 01:53:06 -0400, bitrex <user@example.net> wrote:

On 5/14/19 1:23 AM, Banders wrote:
On 05/13/2019 08:23 PM, Unlisted wrote:
All heated wire filaments whether inside of lightbulbs or vacuum
tubes are now obsolete. They have been replaced by more efficient
florescent bulbs, or the most efficient LED bulbs.

That might turn around. 3 year-old story...

https://www.britishgas.co.uk/business/blog/the-return-of-the-incandescent-light-bulb/

One of those MIT blurbs again

While the idea of reflecting back the useless IR radiation into the
filament is good, but unfortunately tungsten nor any other solid
material can't handle much above 2700 K temperatures.If we had such
materials, we could use electric current as well to reach higher
temperatures.

The reason for incandescent lamp low efficiency is the low filament
temperature of about 2700 K, which has the black body radiation peak
around 1000 nm, in the near IR region. Only a small skirt of this
radiation falls into the usable 380 - 740 nm visible light region.

If we could increase the filament temperature to 6000 K, the black
body radiation peak would fall in the middle of human vision range.

"The old-style bulb was only considered to be 5% efficient, because it
typically lost around 95% of its energy to the air as heat. (You’ll have
noticed this if you ever tried to unscrew a freshly burnt-out bulb.) LED
or fluorescent bulbs boosted that efficiency figure to 14%, but the new
incandescent bulb marks a potentially huge leap for energy efficiency to
40%."

The incandescent lamp has a claimed efficiency of 5 % at 10-12 lm/W.
Reasonably 'white' LEDs have 100-120 lm/W, so th LEDs would have about
50 % efficiency.

Since the theoretical maximum efficiency for white light is about
200-250 klm/W, so that 50 % makes sense also in this respect.

Yowza, where did you get that number? You're off by a factor of at
least 300.

The photopic response peak is at about 540 THz (555 nm in the green).
At that wavelength, 1W gets you 683 lumens (which AFAIK is the largest
prime number ever used for unit conversion).

Cheers

Phil Hobbs


--
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC / Hobbs ElectroOptics
Optics, Electro-optics, Photonics, Analog Electronics
Briarcliff Manor NY 10510

http://electrooptical.net
http://hobbs-eo.com

 

[Phil Hobbs]

On 5/14/19 6:23 PM, Dimitrij Klingbeil wrote:

On 2019-05-14 17:26, Phil Hobbs wrote:
On 5/14/19 5:11 AM, Jeroen Belleman wrote:
upsidedown@downunder.com wrote:
On Tue, 14 May 2019 01:53:06 -0400, bitrex <user@example.net
wrote:

On 5/14/19 1:23 AM, Banders wrote:
On 05/13/2019 08:23 PM, Unlisted wrote:
All heated wire filaments whether inside of lightbulbs or
vacuum tubes are now obsolete. They have been replaced by
more efficient florescent bulbs, or the most efficient LED
bulbs.
That might turn around. 3 year-old story...

https://www.britishgas.co.uk/business/blog/the-return-of-the-incandescent-light-bulb/





One of those MIT blurbs again

While the idea of reflecting back the useless IR radiation into
the filament is good, but unfortunately tungsten nor any other
solid material can't handle much above 2700 K temperatures.If we
had such materials, we could use electric current as well to
reach higher temperatures.


This cannot possibly be an original idea and there's probably a
good reason why it isn't done. Maybe it's too expensive to be worth
the trouble, or the heat or the evaporation of the filament spoils
the filter in short order, or maybe something else yet.

I came across a 1974 patent application of the idea, and I'm sure
it wasn't novel even then.

Jeroen Belleman

Causes gross hotspots on the filament if it's focused back, and
doesn't work well if it isn't, because loss in the coating eventually
dissipates most of the heat before it can be reabsorbed by the
filament.

Looks like it's been tried a while (nearly 40 years) ago:

http://www.lamptech.co.uk/Spec%20Sheets/IN%20WC%20DuroTest%20120-65G30IRC-E26.htm


Again, developed in cooperation with the MIT

There's a fair amount of specsmanship there. A good 100W tungsten bulb
of the pre-2012 sort produces 1690 lumens, whereas that one is listed at
1400. That accounts for almost half the claimed 1.5X efficiency
improvement. They also note the problem with filament sag screwing up
the re-imaging of the filament on itself.

Folks have also tried using nanotextured filaments that emit selectively
at visual wavelengths. I recall trying to help a young woman who was
doing this for her Ph.D. project long ago. It worked pretty well at
first, but the evaporation and redeposition of tungsten screwed up the
texture pretty rapidly. Fortunately that was good enough for her to
graduate--she was very smart and hard-working.

Cheers

Phil Hobbs

--
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC / Hobbs ElectroOptics
Optics, Electro-optics, Photonics, Analog Electronics
Briarcliff Manor NY 10510

http://electrooptical.net
http://hobbs-eo.com

 

On Wed, 15 May 2019 01:21:20 -0400, Phil Hobbs
<pcdhSpamMeSenseless@electrooptical.net> wrote:

On 5/14/19 4:42 AM, upsidedown@downunder.com wrote:
On Tue, 14 May 2019 01:53:06 -0400, bitrex <user@example.net> wrote:

On 5/14/19 1:23 AM, Banders wrote:
On 05/13/2019 08:23 PM, Unlisted wrote:
All heated wire filaments whether inside of lightbulbs or vacuum
tubes are now obsolete. They have been replaced by more efficient
florescent bulbs, or the most efficient LED bulbs.

That might turn around. 3 year-old story...

https://www.britishgas.co.uk/business/blog/the-return-of-the-incandescent-light-bulb/

One of those MIT blurbs again

While the idea of reflecting back the useless IR radiation into the
filament is good, but unfortunately tungsten nor any other solid
material can't handle much above 2700 K temperatures.If we had such
materials, we could use electric current as well to reach higher
temperatures.

The reason for incandescent lamp low efficiency is the low filament
temperature of about 2700 K, which has the black body radiation peak
around 1000 nm, in the near IR region. Only a small skirt of this
radiation falls into the usable 380 - 740 nm visible light region.

If we could increase the filament temperature to 6000 K, the black
body radiation peak would fall in the middle of human vision range.

"The old-style bulb was only considered to be 5% efficient, because it
typically lost around 95% of its energy to the air as heat. (You’ll have
noticed this if you ever tried to unscrew a freshly burnt-out bulb.) LED
or fluorescent bulbs boosted that efficiency figure to 14%, but the new
incandescent bulb marks a potentially huge leap for energy efficiency to
40%."

The incandescent lamp has a claimed efficiency of 5 % at 10-12 lm/W.
Reasonably 'white' LEDs have 100-120 lm/W, so th LEDs would have about
50 % efficiency.

Since the theoretical maximum efficiency for white light is about
200-250 klm/W, so that 50 % makes sense also in this respect.

Sorry typo, I meant to say 200-250 lm/W.

Yowza, where did you get that number? You're off by a factor of at
least 300.

The photopic response peak is at about 540 THz (555 nm in the green).
At that wavelength, 1W gets you 683 lumens (which AFAIK is the largest
prime number ever used for unit conversion).

That 683 lm/W number applies only for 555 nm, the value drops to one
half at 510 and 610 nm and even less further out. Since white light is
supposed to contain all wavelengths, so a weighting value is needed.
It depends on the definition of 'white', what the exact theoretical
limit is, but it is in the 200-250 lm/W ballpark.

Cheers

Phil Hobbs

 

John Larkin <jjlarkin@highland_snip_technology.com> wrote in
news:dokmde5ja0dgufoejo8431nql0eh50p2r7@4ax.com:

On Mon, 13 May 2019 23:59:55 -0700 (PDT), Owen Cook
xemoth@gmail.com> wrote:

On Tuesday, May 14, 2019 at 2:08:12 PM UTC+10, John Larkin wrote:
On Mon, 13 May 2019 23:40:59 -0400, bitrex <user@example.net
wrote:

On 5/13/19 11:23 PM, Unlisted wrote:
In the past, vacuum tubes required a lot of electricity to
operate. Most of that electricity was used to heat the
heating wire, known as the filament, which is very similar to
the filament in an incandescent light bulb. All heated wire
filaments whether inside of lightbulbs or vacuum tubes are
now obsolete. They have been replaced by more efficient
florescent bulbs, or the most efficient LED bulbs.

However, you can not use a LED as a filament inside a vacuum
tube. It would appear to illuminate a tube and look like a
filament, but it would not provide the heat needed to heat
the tube's cathode and thus it will not provide the electron
movement which makes the tube do it's job.

The solution is simple. Provide a hollow cylinder inside the
tube's cathode, where the filament once existed. The user of
the tube must place a lit wax candle inside the tube's
special cathode. The heat from the candle replaces the
electric filament, which makes the tube work as it did
before, but with much less electricity.

But it dont stop there. So far you're only using the heat
from the candle, while the light from the flame is wasted.
Therefore, the tube needs a solar cell inside it's housing,
near the candle's flame. That solar cell produces electricity
from the light of the flame. That electricity is then used to
power the circuit.

But it gets even better, by placing a transistor between the
vacuum tube's cathode, grids, and plate. The flow of free
electrons will bombard the transistor. That will make the
transistor produce between 6 and up to 20 times more power
than a transistor on a circuit board, because of the added
electrons. Add more transistors inside that tube and you will
achieve maximum power. That power combined with the tube's
power will turn a vacuum tube, which once produced a maximum
of (example 20 watts audio output), into a tube now capable
of producing 350 up to 800 watts RMS audio power.

"watts RMS"

TRIGGERED

Different from watts peak. Nothing wrong with that.

The OP is clumsy and not very funny, but there have been
attempts at non-thermionic tubes. It's a very appealing idea,
but none of the cathodes have lasted. Microtips work for a
while, but basicly sputter themselves to death. Ditto carbon
nanotubes.


About 50 odd years ago, a military manpack radio, PRC-25, had a
radio active valve as the final. I believed at the time that the
radioactivity provided the electron flow, rather than a heater,
kind of a battery saving technique.

Some thyratrons had a bit of radioactive gas inside to make ions,
to reduce trigger jitter.

This is my Krytron:

https://www.dropbox.com/s/i2hhyvouro59c6l/Kry_Guts.jpg?dl=0

https://www.dropbox.com/s/7vkdemdk48k3myd/Kry_Danger.jpg?dl=0

That little thing will switch megawatts.

Naaaah...