What is the most powerful vacuum tube ever made?

On 4.8.18 12:01, Piotr Wyderski wrote:
> Tauno Voipio wrote:
> 
>> At least Radio Moscow has run AM on 1 MW power level
> 
> Polish Radio Channel 1 (then at 227kHz) used to run on 2MW,
> feeding the talles antenna mast in world (a full-blown
> half-wave, 646m). EIRP=3MW.
> 
> https://en.wikipedia.org/wiki/Warsaw_radio_mast
> 
> Sometimes it caused dieelectric breakdown and the arc
> current was audio-modulated. This way you could hear our
> supreme leader speaking from the sky. :->
> 
> Then several morons were hired to do some maintenance, with the 
> following result:
> 
> http://www.smartage.pl/wp-content/uploads/2017/11/2-22-300x225@2x.jpg
> 
>      Best regards, Piotr

It was the exchange of the guy ropes going awry.

-- 

-TV

Tauno Voipio wrote:

> It was the exchange of the guy ropes going awry.

The manager of the maintenance team was sentenced to 2.5y in prison.

	Best regards, Piotr

On Fri, 03 Aug 2018 18:54:10 -0700, Jeff Liebermann <jeffl@cruzio.com>
wrote:


>If you really want high power audio, what you want is a pneumatic
>modulator, amplifier, and directional horn:
><https://en.wikipedia.org/wiki/Compressed_air_gramophone>
><https://www.google.com/search?q=auxetophone&tbm=isch>
>Please note that sound are nothing more than controlled changes in air
>pressure.  You don't need a loudspeaker:
><http://wynalazki.andrej.edu.pl/images/duze2/glosnik1.jpg>
>to do that.  Just something that will move lots of air quickly, such
>as a big air compressor.  For example, if you happen to have a 150
>horsepower air compressor, and high power fluidics (air is a
>compressible fluid) modulator and amplifier handy, you can build
>rather high power sound system:
><https://www.psaudio.com/article/the-mother-of-all-speakers-moas/>
><http://www.noiseaddicts.com/2008/09/loudest-speaker-in-the-world/>
>   150 hp * 745 watts/hp = 112,000 watts maximum audio power
>Actually, it's only about half that, since it takes almost as much
>power to run the modulator as it does to product the output pressure
>changes.

There is a much larger speaker at the Redstone Arsenal in Huntsville.
It's about 60 ft tall and an approx 30 ft square at the bottom.  It is
a folded exponential horn.

It was designed to make the same level of sound that the scientists
estimated the Saturn 5 would make.  It is aimed off the reservation so
they could assess any damage that SPL would cause.

My cousin was the Chief Metallurgist for the Army at the Arsenal.  He
got me pretty free access to the base.  When I was about 15, he took
me over to see and explore the horn.  I climbed all over it but I
don't remember many details.  I do recall seeing several large diesel
engines on the site so the audio drive probably was pneumatic like the
MOAS.

About 15 years ago, not long before he was to die from Chron's
disease, he took us on another tour of the Arsenal.  The speaker was
still there and bore a brass plaque stating that it was a National
Historic Site.

Unfortunately, Google came up with nothing.  Strange.

John
John DeArmond
http://www.neon-john.com
http://www.tnduction.com 
Tellico Plains, Occupied TN
See website for email address

On Sat, 04 Aug 2018 11:39:20 -0400, Neon John <no@never.com> wrote:

>There is a much larger speaker at the Redstone Arsenal in Huntsville.
>It's about 60 ft tall and an approx 30 ft square at the bottom.  It is
>a folded exponential horn.
>
>It was designed to make the same level of sound that the scientists
>estimated the Saturn 5 would make.  It is aimed off the reservation so
>they could assess any damage that SPL would cause.

I found a rather vague reference to such a horn under a history of the
Saturn test (F1 engine).  See Pg 94:
<https://the-eye.eu/public/concen.org/The%20Saturn%20Myth%20Occult%20Symbolism%20Saturn%20Worship/Stages%20to%20Saturn.pdf>
(30.8MB)  
   Reverberations of the Saturn tests were quickly felt. The
   acoustical impact was quite evident in the immediate area 
   around the city of Huntsville, and the long-range sound 
   propagation occurred at distances up to 160 kilometers. 
   The result was a rash of accidental damage to windows and 
   wall plaster, followed by a rash of damage claims (some-
   times filed by citizens on days when no tests had been 
   conducted). Aware that climatic conditions caused very 
   pronounced differences in noise levels and long-range 
   sound propagation, engineers began taking meteorological 
   soundings and installed a huge acoustical horn atop a tower 
   in the vicinity of the test area. No ordinary tooter, the 
   horn was over 7.6 meters long and had a huge flared aperture 
   over 4.6 meters high. Its sonorous gawps, bounced off a 
   network of sound recorders, gave acoustical engineers a 
   good idea whether it was safe to fire the big rockets on 
   overcast days.

There are some low quality photographs in the 500 page book, but none
showing a big horn.  However, I did find this photo:
<https://www.al.com/living/index.ssf/2016/12/weird_vintage_alabama_photos_t.html>
which seems to fit the aforementioned dimensions and description:
<https://www.al.com/living/index.ssf/2016/12/weird_vintage_alabama_photos_t.html>
<https://image.al.com/home/bama-media/width620/img/living_impact/photo/hayes-horn-1966jpg-490339bdc40cf807.jpg>
I would have expected it to be much longer.

In another document, the sound level at the shopping center was
measured at 118dB.  I'm surprised it didn't break windows and ear
drums.  See Pg18:
<http://lcweb2.loc.gov/master/pnp/habshaer/al/al1100/al1196/data/al1196data.pdf>
(1.3MB)

>My cousin was the Chief Metallurgist for the Army at the Arsenal.  He
>got me pretty free access to the base.  When I was about 15, he took
>me over to see and explore the horn.  I climbed all over it but I
>don't remember many details.  I do recall seeing several large diesel
>engines on the site so the audio drive probably was pneumatic like the
>MOAS.

Yep.  Big diesel powered air compressors were what drove such
speakers.  I vaguely recall that some were powered by a diesel train
engine but might be mistaken.  I suspect that the release of all that
pressure would probably have frozen any water in the air and turned it
into a snow blower.  I don't recall any mention of that problem.  Like
a musical horn, the low frequency limit is controlled by the length of
the horn, while the high frequency end is limited by the modulator.
The Huntsville horn was trying in mimic the F1 engine(s), which
according to the history, resonated at 5.25Hz.  That requires are
really long and probably folded horn.  The battlefield horn carries
voice grade audio, where the bottom limit was about 300Hz, and could
therefore be much shorter.  

>About 15 years ago, not long before he was to die from Chron's
>disease, he took us on another tour of the Arsenal.  The speaker was
>still there and bore a brass plaque stating that it was a National
>Historic Site.
>
>Unfortunately, Google came up with nothing.  Strange.

I found the photo with an image search using:
<https://www.google.com/search?tbm=isch&q=redstone+arsenal+horn>
and the documents by manually groveling through:
<https://www.google.com/search?q=redstone+arsenal+%22horn%22+saturn+5>
Note the quotes around "horn" which makes it mandatory to have the
word "horn" in the initial search results.

>John
>John DeArmond
>http://www.neon-john.com
>http://www.tnduction.com 
>Tellico Plains, Occupied TN
>See website for email address

-- 
Jeff Liebermann     jeffl@cruzio.com
150 Felker St #D    http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann     AE6KS    831-336-2558

On Sat, 04 Aug 2018 11:26:49 -0700, Jeff Liebermann <jeffl@cruzio.com>
wrote:



>   ... installed a huge acoustical horn atop a tower 
>   in the vicinity of the test area. No ordinary tooter, the 
>   horn was over 7.6 meters long and had a huge flared aperture 
>   over 4.6 meters high.

Here's the audiophile version of the Saturn 5 test horn:
<http://www.mh-audio.nl/Horn/GExpoHorn.asp>
Clever design methinks but I don't think I want it in my house.

Trying to see what the 4.6 meter diameter test horn would do, I
plugged these numbers into the calculator;
  Low cutoff frequency = 5Hz
  Throat diameter = 460 cm  (4.6 meters)
  Steps = 25
which resulted in a horn length = 1692.3 cm or 17 meters long.  That's
much longer than the Saturn 5 test horn, which suggests that it wasn't
intended to mimic engine vibrations.  

Interactively plugging numbers for the low end cutoff frequency, I
get:
  low freq cutoff = 7.9 Hz
  horn length = 756 cm
Close enough.  So, the big horn was good for about 8Hz.



-- 
Jeff Liebermann     jeffl@cruzio.com
150 Felker St #D    http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann     AE6KS    831-336-2558

Largest continuous duty, that's relevant to your application (i.e. not RF) 
is the 8974, 1.5MW plate dissipation.

5kW is rather pedestrian for industrial applications; they're still being 
maintained and sold, probably on the cheap side of things.  Commercial 
applications otherwise (like radiotransmitters) are basically all solid 
state now, for good reason.

Tim

-- 
Seven Transistor Labs, LLC
Electrical Engineering Consultation and Design
Website: https://www.seventransistorlabs.com/

<oldschool@tubes.com> wrote in message 
news:kjr7mdte459o2ll2fo8mp48j98afrfisks@4ax.com...
> What is the most powerful vacuum tube ever made?
>
> I'm looking into building the most pewerful tube audio amplifier
> possible. I'll be using 4 tubes in push-pull parallel. (per channel). My
> goal is at least 5000 watts RMS per channel (if possible). I will likely
> rewind some pole pigs (power pole transformers) for output transformers,
> and possibly use one of them in reverse for the power supply
> transformer, which should supply 3250 to 7500 volts to the plates (or up
> to 15KV if I use a different pole pig rated for higher primary voltage).
>
> 

On 04/08/2018 14:44, Jeff Liebermann wrote:
> On Sat, 04 Aug 2018 06:52:49 +0300, upsidedown@downunder.com wrote:
> 
>> On Fri, 03 Aug 2018 18:54:10 -0700, Jeff Liebermann <jeffl@cruzio.com>
>> wrote:
>>
>>>
>>>> I'm looking into building the most pewerful tube audio amplifier
>>>> possible. I'll be using 4 tubes in push-pull parallel. (per channel). My
>>>> goal is at least 5000 watts RMS per channel (if possible). I will likely
>>>> rewind some pole pigs (power pole transformers) for output transformers,
>>>> and possibly use one of them in reverse for the power supply
>>>> transformer, which should supply 3250 to 7500 volts to the plates (or up
>>>> to 15KV if I use a different pole pig rated for higher primary voltage).
>>>
>>> You're probably ok at 3250 to 7500 volts, but 15kV will probably turn
>>> your audio amplifier into an x-ray generator.  Have your lead shielded
>>> underwear handy.
> 
>> Not an issue with full wave rectified 15 kVac.
>>
>> Below 25kVdc, the X-ray spectrum is just the continuum, above 25 kV
>> nasty discrete X-ray lines will also appear. For this reason the power
>> supply for old shadow mask CRTs also contained a shunt regulator (like
>> the PD500 power triode) to limit the CRT anode voltage to 25 kV.
> 
> Thanks.  I couldn't recall at what voltage the problems start and was
> too lazy to check.  Looks like 20kV is where a vacuum tube starts to
> produce x-rays.  Interesting video shows how it works:
> "Creating X-rays with a standard vacuum tube"
> <https://www.youtube.com/watch?v=yLSu_UjrcUA>
> 
> I've tried this experiment with various vacuum tubes.  My voltage
> source was smaller and only went to 25kV (powder coating paint gun):
> <https://www.eastwood.com/eastwood-dual-voltage-powder-gun-starter-kit.html>
> so I didn't see the continuous x-rays as in the video at 30kV.
> 


I can't find it now, but I saw on youtube someone detecting significant 
amounts of xrays from a vacuum tube at 5kV. I think the problem is that 
most detectors are insensitive to low energy xray photons so people 
think there is no emission, but depending on the glass envelope, there 
might be, it is just hard to detect apart from by waiting for it to 
disrupt your DNA. Below 5kV there are definitely xrays within the vacuum 
tube, the question is whether or not they can get out. I would certainly 
suggest being very careful at even 5kV, and don't trust you xray 
detector to work for low energy xray photons, unless you have a good 
reason to.

Chris Jones wrote:
>I can't find it now, but I saw on youtube someone detecting significant 
>amounts of xrays from a vacuum tube at 5kV. I think the problem is that 
>most detectors are insensitive to low energy xray photons so people 
>think there is no emission, but depending on the glass envelope, there 
>might be, it is just hard to detect apart from by waiting for it to 
>disrupt your DNA. Below 5kV there are definitely xrays within the vacuum 
>tube, the question is whether or not they can get out. I would certainly 
>suggest being very careful at even 5kV, and don't trust you xray 
>detector to work for low energy xray photons, unless you have a good 
>reason to.

Some geiger counters can also make good X-ray detectors:
 https://en.wikipedia.org/wiki/Geiger_counter

I have a couple of those in use, of various types.

On Sun, 5 Aug 2018 16:30:39 +1000, Chris Jones
<lugnut808@spam.yahoo.com> wrote:

>On 04/08/2018 14:44, Jeff Liebermann wrote:
>> On Sat, 04 Aug 2018 06:52:49 +0300, upsidedown@downunder.com wrote:
>> 
>>> On Fri, 03 Aug 2018 18:54:10 -0700, Jeff Liebermann <jeffl@cruzio.com>
>>> wrote:
>>>
>>>>
>>>>> I'm looking into building the most pewerful tube audio amplifier
>>>>> possible. I'll be using 4 tubes in push-pull parallel. (per channel). My
>>>>> goal is at least 5000 watts RMS per channel (if possible). I will likely
>>>>> rewind some pole pigs (power pole transformers) for output transformers,
>>>>> and possibly use one of them in reverse for the power supply
>>>>> transformer, which should supply 3250 to 7500 volts to the plates (or up
>>>>> to 15KV if I use a different pole pig rated for higher primary voltage).
>>>>
>>>> You're probably ok at 3250 to 7500 volts, but 15kV will probably turn
>>>> your audio amplifier into an x-ray generator.  Have your lead shielded
>>>> underwear handy.
>> 
>>> Not an issue with full wave rectified 15 kVac.
>>>
>>> Below 25kVdc, the X-ray spectrum is just the continuum, above 25 kV
>>> nasty discrete X-ray lines will also appear. For this reason the power
>>> supply for old shadow mask CRTs also contained a shunt regulator (like
>>> the PD500 power triode) to limit the CRT anode voltage to 25 kV.
>> 
>> Thanks.  I couldn't recall at what voltage the problems start and was
>> too lazy to check.  Looks like 20kV is where a vacuum tube starts to
>> produce x-rays.  Interesting video shows how it works:
>> "Creating X-rays with a standard vacuum tube"
>> <https://www.youtube.com/watch?v=yLSu_UjrcUA>
>> 
>> I've tried this experiment with various vacuum tubes.  My voltage
>> source was smaller and only went to 25kV (powder coating paint gun):
>> <https://www.eastwood.com/eastwood-dual-voltage-powder-gun-starter-kit.html>
>> so I didn't see the continuous x-rays as in the video at 30kV.
>> 
>
>
>I can't find it now, but I saw on youtube someone detecting significant 
>amounts of xrays from a vacuum tube at 5kV. I think the problem is that 
>most detectors are insensitive to low energy xray photons so people 
>think there is no emission, but depending on the glass envelope, there 
>might be, it is just hard to detect apart from by waiting for it to 
>disrupt your DNA. Below 5kV there are definitely xrays within the vacuum 
>tube, the question is whether or not they can get out. I would certainly 
>suggest being very careful at even 5kV, and don't trust you xray 
>detector to work for low energy xray photons, unless you have a good 
>reason to.

The continuous X-ray spectrum looks very much like black-body
radiation. There is a distinct peak, which frequency direct
proportional to frequency (hence inversely proportional to wavelength)
to the electron energy (in keV), while in standard black-body
radiation the wavelength is inversely proportional to temperature.
When viewed on a log-log graph, in both cases the slope is steeper on
the shorter wavelength side and so on. Some physics text books even
suggests that it _is_ the same phenomenon.

At 5 keV, the total X-radiation is more than two orders of magnitude
below that of 25 keV, so not to worry about the radiation at 5 kV
anode voltage.

Up to  about 25 kV, the spectrum looks just like black-body radiation.
At higher voltages, there are discrete spectral lines (depending on
target material), in addition to the black.body continuum.

On Sat, 4 Aug 2018 23:29:23 -0500, "Tim Williams"
<tiwill@seventransistorlabs.com> wrote:

>Largest continuous duty, that's relevant to your application (i.e. not RF) 
>is the 8974, 1.5MW plate dissipation.

RF tubes are OK as long as you can amplitude them. Just add an
envelope detector (diode detector) and drive the speaker. Make sure
you handle  the detector DC bias issue.

>5kW is rather pedestrian for industrial applications; they're still being 
>maintained and sold, probably on the cheap side of things.  Commercial 
>applications otherwise (like radiotransmitters) are basically all solid 
>state now, for good reason.
>
>Tim