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Author Topic: Background Radiation - Could It Be a Vexation ?  (Read 41610 times)
AG6K
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« Reply #75 on: October 30, 2011, 02:15:40 PM »

Quote
AF6LJ
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RE: Background Radiation - Could It Be a Vexation ?
« Reply #72 on: Today at 10:07:10 AM »
   
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Okay a little perspective here.

If the tube is cut off no current is going to flow if a few thousand electrons are somehow, some way knocked loose. Would this be enough to overcome the bias if the tube is cut off twice or three times past cutoff.?  No it wouldn't.

  Would the presence of bias V disapppear the bumped loose electrons?


Quote
That resonant circuit could have a Q of 5000 and if there isn't enough electrons to cause current to flow, no Ringy-dingy no regeneration, no big bang caused by background radiation or anything else for that matter.

Rich;
If the tube is cut off, it's cut off there must be electrons flowing from cathode to anode for there to be any kind of oscillation.

  The electrons that are bumped loose could come from anything inside the envelope.

Quote
To address something you brought up several posts back; I have no doubt 90-100MHZ spurs are seen on a spectrum analyzer when you send a series of dits or use a pulser to drive the exciter; the real question is how far below the PEP output of the fundamental are those spurs?

  During the test the RF input and output is shorted and the pulser keys the T/R relay so that ZSAC go off and on repeatedly.   The spectrum analyzer probe is placed a couple of inches from the anodes.


Quote
Back in the day I tuned S and L band emitter driven transistor amplifiers, it was extremely difficult to build an amplifier that didn't have some resonant component in the output or input that existed along with the matching networks. You just don't want them to have a very high Q.

 This is what General Electric's G.W. Fyler told us in 1935. 
Conclusions

"In the elimination of parasites from a transrmitter, the circuits should be kept as simple as possib1e to prevent complex resonance condition.. Radio frequency choke coils and shuntfeed circuits should be kept at a minimum. Wide band neutralization circuits are desirable. The grids of vacuum tubes should be effectIvely by-passed capacitively to the cathode through a capacity, and inductance added next to the plates of the tubes to eliminate shortwave parasites. If necessary, the plate or grid parasitic circuits should be damped with resistance. Inductively coupled rather than capacitively coupled Input and output circuits should be used wherever possible. The mechanical layout of a shortwave transmitter should be well planned with short lesds and compact tank circuits to keep the current where it is supposed to be and to minimize stray coupling between circuits."

G. W. Fyler September, 1935

Quote
And as a bit of trivia;
From what I remember one ampere second is 6.2 x 1023 electrons per second. I could be off by a couple of orders of magnitude however you get the idea you have to knock off a lot of electrons to raise the anode current in a tube, even to raise the tube's anode current by one femto amp. 1 x 10-15 amperes.

  If the tube has VHF amplifying ability, then what?

Quote
... ... ...
Rich;
If by some means electrons get knocked off it's doubtful if there would be any current flowing since for an instant the anode would be more positive than the instant before but since the distance those electrons would have traveled would be so short no plate current would flow as a result of this action.

  So  electrons that come from the 3-500Z's Th-W filament are attracted by the + several kV on the anode - and anode current flows, but electrons that get knocked off of say Mo atoms in the grid wires are not attracted by the + several kV -  so no current flows and no ringy dingy results?
cheers
• Rich, ag6k

Quote
Electrons are in motion all the time in that anode the few that would had been freed would simply add to the random motion of the guzillons of electrons that were in motion at that instant.

Okay see Y'all later off to the dog show.
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AG6K
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« Reply #76 on: October 30, 2011, 02:27:04 PM »

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AF9J
   
RE: Background Radiation - Could It Be a Vexation ?
« Reply #69 on: Today at 09:04:03 AM »
   
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Rich, you're forgetting that a Geiger counter has a gas that will avalanche conduct, much more readily than the (mostly vacuum) that a power tube has.

  the power tube does not avalanche or arc internally.   
Who said it did ?
•  Rich, ag6k


 
Quote
...
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G3RZP
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« Reply #77 on: October 30, 2011, 02:31:23 PM »

But the amount of electrons that could be produced by a collision is too small to initiate the effects claimed. If heavy neutron bombardment can't do it, a cosmic ray won't!

Really, Rich, you should take to writing science fiction or science fantasy. It would probably pay better, too.
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AG6K
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« Reply #78 on: October 30, 2011, 02:39:01 PM »

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G3RZP, Peter C.

RE: Background Radiation - Could It Be a Vexation ?
« Reply #71 on: Today at 09:53:09 AM »
   
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One of the old MIL STD Handbooks (might have been 217) had some data on reliability of tubes under irradiation. Since they were irradiating with neutrons in very large speeds and densities, (which would be more likely to knock electrons out) with tubes under power and got very long lives, it seems more than unlikely.

In any case, to make the parasitic circuit ring with any amplitude, it will need a pretty large current pulse even with a Q of 10. That is not even a few electrons.

  Peter:  What if the electron tube has a  modest amount of amplification at the VHF parasitic -resonance in its anode circuit?
•  Rich, ag6k
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N4MPM
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« Reply #79 on: October 30, 2011, 03:08:48 PM »

This is beginning to resemble the story about Pig wrestling. Tongue Roll Eyes Shocked
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W8JI
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« Reply #80 on: October 30, 2011, 04:24:21 PM »

This is beginning to resemble the story about Pig wrestling. Tongue Roll Eyes Shocked

The rational, logical, educational value of this forum took a big hit a few weeks ago. It's almost like the Twilight Zone now.
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AF6LJ
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« Reply #81 on: October 30, 2011, 05:27:09 PM »

Quote

  the power tube does not avalanche or arc internally.   
Who said it did ?
•  Rich, ag6k

See your very first posts in this thread Rich for the answer to this.






The fork came up clean a day or so ago, I think this thread is done.

Have a nice day everyone and thanks for the interesting exchange. Oh and.. We left with a dog and came home with a Champion for anyone who cares Smiley

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AG6K
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« Reply #82 on: October 30, 2011, 06:04:42 PM »

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AF6LJ
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RE: Background Radiation - Could It Be a Vexation ?
« Reply #81 on: Today at 05:27:09 PM »
   
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Quote

  the power tube does not avalanche or arc internally.   
Who said it did ?
•  Rich, ag6k

See your very first posts in this thread Rich for the answer to this.

  My position has always been that an arc which makes a big bang can not be  inside a vacuum tube.
Rich, ag6k
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AG6K
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« Reply #83 on: October 30, 2011, 06:07:23 PM »

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W8JI
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RE: Background Radiation - Could It Be a Vexation ?
« Reply #80 on: Today at 04:24:21 PM »
   
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Quote from: N4MPM on Today at 03:08:48 PM
This is beginning to resemble the story about Pig wrestling. Tongue Roll Eyes Shocked

The rational, logical, educational value of this forum took a big hit a few weeks ago. It's almost like the Twilight Zone now.

  Tom R.:  Did you see the aurora in Georgia?
Rich, ag6k
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W8JI
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« Reply #84 on: October 30, 2011, 11:35:29 PM »

Have a nice day everyone and thanks for the interesting exchange. Oh and.. We left with a dog and came home with a Champion for anyone who cares Smiley



At least there is something useful and of interest in this thread.

What kind of dog? We raise what we are gifted. People dump their unwanted dogs on our road, because it is a very rural dirt road. I have cameras now that record license numbers. Once in a while a photon blurs the license number, it almost looks like dust but I know it can't ever be the most obvious. :-)

 
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AF6LJ
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« Reply #85 on: October 31, 2011, 05:25:51 AM »

Have a nice day everyone and thanks for the interesting exchange. Oh and.. We left with a dog and came home with a Champion for anyone who cares Smiley



At least there is something useful and of interest in this thread.

What kind of dog? We raise what we are gifted. People dump their unwanted dogs on our road, because it is a very rural dirt road. I have cameras now that record license numbers. Once in a while a photon blurs the license number, it almost looks like dust but I know it can't ever be the most obvious. :-)

 

Chesapeake Bay Retrievers, my roommate has two.
One spayed bitch that isn't show quality, and her boy who just made breed conformation.

We now return you to our regularly scheduled thread.  
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N2EY
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« Reply #86 on: October 31, 2011, 05:56:35 AM »

To answer the title question:

No, it couldn't.

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AG6K
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« Reply #87 on: October 31, 2011, 07:21:20 AM »

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AG6K
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RE: Background Radiation - Could It Be a Vexation ?
« Reply #75 on: Yesterday at 02:15:40 PM »
   
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AF6LJ
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RE: Background Radiation - Could It Be a Vexation ?
« Reply #72 on: Today at 10:07:10 AM »
   
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Okay a little perspective here.

If the tube is cut off no current is going to flow if a few thousand electrons are somehow, some way knocked loose. Would this be enough to overcome the bias if the tube is cut off twice or three times past cutoff.?  No it wouldn't.

  Would the presence of bias V disapppear the bumped loose electrons?


Quote
That resonant circuit could have a Q of 5000 and if there isn't enough electrons to cause current to flow, no Ringy-dingy no regeneration, no big bang caused by background radiation or anything else for that matter.

Rich;
If the tube is cut off, it's cut off there must be electrons flowing from cathode to anode for there to be any kind of oscillation.

  The electrons that are bumped loose could come from anything inside the envelope.

Quote
To address something you brought up several posts back; I have no doubt 90-100MHZ spurs are seen on a spectrum analyzer when you send a series of dits or use a pulser to drive the exciter; the real question is how far below the PEP output of the fundamental are those spurs?

  During the test the RF input and output is shorted and the pulser keys the T/R relay so that ZSAC go off and on repeatedly.   The spectrum analyzer probe is placed a couple of inches from the anodes.


Quote
Back in the day I tuned S and L band emitter driven transistor amplifiers, it was extremely difficult to build an amplifier that didn't have some resonant component in the output or input that existed along with the matching networks. You just don't want them to have a very high Q.

 This is what General Electric's G.W. Fyler told us in 1935.
Conclusions

"In the elimination of parasites from a transrmitter, the circuits should be kept as simple as possib1e to prevent complex resonance condition.. Radio frequency choke coils and shuntfeed circuits should be kept at a minimum. Wide band neutralization circuits are desirable. The grids of vacuum tubes should be effectIvely by-passed capacitively to the cathode through a capacity, and inductance added next to the plates of the tubes to eliminate shortwave parasites. If necessary, the plate or grid parasitic circuits should be damped with resistance. Inductively coupled rather than capacitively coupled Input and output circuits should be used wherever possible. The mechanical layout of a shortwave transmitter should be well planned with short lesds and compact tank circuits to keep the current where it is supposed to be and to minimize stray coupling between circuits."

G. W. Fyler September, 1935

Quote
And as a bit of trivia;
From what I remember one ampere second is 6.2 x 1023 electrons per second. I could be off by a couple of orders of magnitude however you get the idea you have to knock off a lot of electrons to raise the anode current in a tube, even to raise the tube's anode current by one femto amp. 1 x 10-15 amperes.

  If the tube has VHF amplifying ability, then what?

Quote
... ... ...
Rich;
If by some means electrons get knocked off it's doubtful if there would be any current flowing since for an instant the anode would be more positive than the instant before but since the distance those electrons would have traveled would be so short no plate current would flow as a result of this action.

  So  electrons that come from the 3-500Z's Th-W filament are attracted by the + several kV on the anode - and anode current flows, but electrons that get knocked off of say Mo atoms in the grid wires are not attracted by the + several kV -  so no current flows and no ringy dingy results?
cheers
• Rich, ag6k

Quote
Electrons are in motion all the time in that anode the few that would had been freed would simply add to the random motion of the guzillons of electrons that were in motion at that instant.

Okay see Y'all later off to the dog show.
   Report to moderator   208.127.237.34
AG6K
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RE: Background Radiation - Could It Be a Vexation ?
« Reply #76 on: Yesterday at 02:27:04 PM »
   
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AF9J
   
RE: Background Radiation - Could It Be a Vexation ?
« Reply #69 on: Today at 09:04:03 AM »
   
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Rich, you're forgetting that a Geiger counter has a gas that will avalanche conduct, much more readily than the (mostly vacuum) that a power tube has.

  the power tube does not avalanche or arc internally.   
Who said it did ?
•  Rich, ag6k


 
Quote
...
   Report to moderator   208.127.237.34
G3RZP
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RE: Background Radiation - Could It Be a Vexation ?
« Reply #77 on: Yesterday at 02:31:23 PM »
   
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But the amount of electrons that could be produced by a collision is too small to initiate the effects claimed. If heavy neutron bombardment can't do it, a cosmic ray won't!

Really, Rich, you should take to writing science fiction or science fantasy. It would probably pay better, too.
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AG6K
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RE: Background Radiation - Could It Be a Vexation ?
« Reply #78 on: Yesterday at 02:39:01 PM »
   
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G3RZP, Peter C.

RE: Background Radiation - Could It Be a Vexation ?
« Reply #71 on: Today at 09:53:09 AM »
   
Reply with quoteQuote
One of the old MIL STD Handbooks (might have been 217) had some data on reliability of tubes under irradiation. Since they were irradiating with neutrons in very large speeds and densities, (which would be more likely to knock electrons out) with tubes under power and got very long lives, it seems more than unlikely.

In any case, to make the parasitic circuit ring with any amplitude, it will need a pretty large current pulse even with a Q of 10. That is not even a few electrons.

  Peter:  What if the electron tube has a  modest amount of amplification at the VHF parasitic -resonance in its anode circuit?
•  Rich, ag6k
   Report to moderator   208.127.237.34
N4MPM
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RE: Background Radiation - Could It Be a Vexation ?
« Reply #79 on: Yesterday at 03:08:48 PM »
   
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This is beginning to resemble the story about Pig wrestling. Tongue Roll Eyes Shocked

  It's a story about wrestling with the truth about high-energy photons ability to bust loose electrons.  The laugher is that the recent ionized N2 (red) aurora seen in the State of Georgia - where the Doubting Thomas lives - is estimated to have had a current of >1,000,000 Amperes - or 6.24 x 10^24 electrons.
Rich, ag6k
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AG6K
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« Reply #88 on: October 31, 2011, 07:37:14 AM »

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AF6LJ
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RE: Background Radiation - Could It Be a Vexation ?
« Reply #81 on: Yesterday at 05:27:09 PM »
   
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Quote

  the power tube does not avalanche or arc internally.   
Who said it did ?
•  Rich, ag6k

See your very first posts in this thread Rich for the answer to this.

  I looked and I saw no place where I said an arc was inside the tube.   How about posting a quote?  tnx
  I have never autopsied a tube that was gassy/glowed blue with HV -  that had an arc mark on the anode - but I've seen lots of arced bandswitches and pitted Tune-C plates in amps that had a history of big bangs.

Rich, ag6k
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AG6K
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« Reply #89 on: October 31, 2011, 07:44:28 AM »

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RE: Background Radiation - Could It Be a Vexation ?
« Reply #84 on: Yesterday at 11:35:29 PM »
   
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Quote from: AF6LJ on Yesterday at 05:27:09 PM
Have a nice day everyone and thanks for the interesting exchange. Oh and.. We left with a dog and came home with a Champion for anyone who cares Smiley



At least there is something useful and of interest in this thread.

What kind of dog? We raise what we are gifted. People dump their unwanted dogs on our road, because it is a very rural dirt road. I have cameras now that record license numbers. Once in a while a photon blurs the license number, it almost looks like dust but I know it can't ever be the most obvious. :-)

 
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AF6LJ
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RE: Background Radiation - Could It Be a Vexation ?
« Reply #85 on: Today at 05:25:51 AM »
   
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Quote from: W8JI on Yesterday at 11:35:29 PM
Quote from: AF6LJ on Yesterday at 05:27:09 PM
Have a nice day everyone and thanks for the interesting exchange. Oh and.. We left with a dog and came home with a Champion for anyone who cares Smiley



At least there is something useful and of interest in this thread.

What kind of dog? We raise what we are gifted. People dump their unwanted dogs on our road, because it is a very rural dirt road. I have cameras now that record license numbers. Once in a while a photon blurs the license number, it almost looks like dust but I know it can't ever be the most obvious. :-)

 

Chesapeake Bay Retrievers, my roommate has two.
One spayed bitch that isn't show quality, and her boy who just made breed conformation.

We now return you to our regularly scheduled thread. 

   the lingering smell of red herring?

Rich, ag6k
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