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Author Topic: Background Radiation - Could It Be a Vexation ?  (Read 41611 times)
QRP4U2
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Posts: 262




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« Reply #90 on: October 31, 2011, 10:38:15 AM »

Rich,

Regarding Auroras:

Now you're talking about another entirely different mechanism: the collision of energetic charged particles from the Sun with atoms in the thermosphere that interact with the Earth's magnetic field.

 Phil - AC0OB
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AC0OB - A Place Where Thermionic Emitters Rule!
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Besides, when you're a Ham, you experiment with and improve boat anchors - that's what you do!. Smiley
AG6K
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« Reply #91 on: October 31, 2011, 11:58:09 AM »

   
RE: Background Radiation - Could It Be a Vexation ?
« Reply #90 on: Today at 10:38:15 AM »
   
Rich,

Regarding Auroras:

Now you're talking about another entirely different mechanism: the collision of energetic charged particles from the Sun with atoms in the thermosphere that interact with the Earth's magnetic field.

 Phil - AC0OB
[/quote]

  Charged particles contribute to auroras, but. higher energy photons of EM radiation also contribute to auroras because they can also bump  electrons into a higher orbit, and when these  electrons fall back into a lower orbit  they emit photons at a specific wavelength - such as red for N2, UV for Hg,  and blue for O2.  Higher energy photons cause conduction in Geiger-Muller tubes, and they can cause momentary  current flow in vacuum tubes. 
Rich, ag6k
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M0HCN
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Posts: 566




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« Reply #92 on: October 31, 2011, 01:56:44 PM »

But nowhere near enough to be in any way significant without gas to provide for avalanche breakdown......

Do the math already, this is not hard to demonstrate, dV=dQ/C, grid capacitance and the charge on the electron, work it from there, not hard. This is high school level physics, not exactly university level stuff (I wish this forum software supported LaTEX markup).

Hell getting a non avalanche breakdown tube to work as a particle detector takes MAJOR effort with the preamplifier and that is with a tube designed for proportional counting, look at the pain folks have getting helium three neutron detector tubes to work without excess noise.

You really need to look to ordinary physics here, think forces between current carrying conductors, magnetorestriction, that kind of stuff, not weird shit happening in the switching device (Be it conventional tube, spark gap, thyratron or large solid state switch), bangs in high energy electronics are not always the result of a arc occurring where it can be directly seen or heard.

Regards, Dan.
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AG6K
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« Reply #93 on: October 31, 2011, 02:34:59 PM »

Quote
2E0CHE
   
RE: Background Radiation - Could It Be a Vexation ?
« Reply #92 on: Today at 01:56:44 PM »
   
But nowhere near enough to be in any way significant without gas to provide for avalanche breakdown.... ... ... ..

  One more time:  Hello,   There is no breakdown or arc inside the tube.  The tube briefly conducts, rings the anode-circuit's parasitic VHF resonance, which makes a damped wave VHF signal - which is than amplified and re-amplified until things largely run amok because VHF energy can not pass through the LowPass Pi-tank to reach the load.
Rich, ag6k

...
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AF6LJ
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Posts: 2




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« Reply #94 on: October 31, 2011, 03:06:53 PM »

Quote
2E0CHE
   
RE: Background Radiation - Could It Be a Vexation ?
« Reply #92 on: Today at 01:56:44 PM »
   
But nowhere near enough to be in any way significant without gas to provide for avalanche breakdown.... ... ... ..

  One more time:  Hello,   There is no breakdown or arc inside the tube.  The tube briefly conducts, rings the anode-circuit's parasitic VHF resonance, which makes a damped wave VHF signal - which is than amplified and re-amplified until things largely run amok because VHF energy can not pass through the LowPass Pi-tank to reach the load.
Rich, ag6k

...

This can't happen if the amplifier is sitting idle, it can't even happen in a properly designed amplifier.
There isn't going to be enough electrons dislodged by some cosmic ray, or high energy photon.

If this could even happen, how do you think we would have made it to the moon and back as many times as we did?

There is nowhere on the net I can find any documentation for this ever occurring.
Nobody has written any papers on this.

Your Geiger tube does it because there is a large bias on the electrodes and the gas inside is at a rather low pressure.
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W8JI
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« Reply #95 on: October 31, 2011, 04:40:04 PM »

Summary of AG6K's tube arc proof in a 4-1000 amplifier:

1.) There is aurora

2.)  Gas filled HV Geiger-Muller tubes occasionally have a few microampere "tic" when exposed to room radiation

3.) A Prius computer occasionally locks up

4.) Someone said a spectrum analyzer shows a 100MHz pulse when an SB220's relay is rapidly keyed off and on with shorted input and output ports and a probe inches from the anode

5.) A bell does not ring in a vacuum

6.) Sue's dog is a red herring

 
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AG6K
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« Reply #96 on: October 31, 2011, 05:15:22 PM »

Quote
W8JI
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Posts: 7729


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RE: Background Radiation - Could It Be a Vexation ?
« Reply #95 on: Today at 04:40:04 PM »
   
Summary of AG6K's tube arc proof in a 4-1000 amplifier:

1.) There is aurora

2.)  Gas filled HV Geiger-Muller tubes occasionally have a few microampere "tic" when exposed to room radiation

3.) A Prius computer occasionally locks up

4.) Someone said a spectrum analyzer shows a 100MHz pulse when an SB220's relay is rapidly keyed off and on with shorted input and output ports and a probe inches from the anode

5.) A bell does not ring in a vacuum

6.) Sue's dog is a red herring

  where's the proof  that I said the tube arced?
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AG6K
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« Reply #97 on: October 31, 2011, 05:37:21 PM »

Quote
AF6LJ
Susan
   
RE: Background Radiation - Could It Be a Vexation ?
« Reply #94 on: Today at 03:06:53 PM »
   
Reply with quoteQuote
Quote from: AG6K on Today at 02:34:59 PM
Quote
2E0CHE
   
RE: Background Radiation - Could It Be a Vexation ?
« Reply #92 on: Today at 01:56:44 PM »
   
But nowhere near enough to be in any way significant without gas to provide for avalanche breakdown.... ... ... ..

  One more time:  Hello,   There is no breakdown or arc inside the tube.  The tube briefly conducts, rings the anode-circuit's parasitic VHF resonance, which makes a damped wave VHF signal - which is than amplified and re-amplified until things largely run amok because VHF energy can not pass through the LowPass Pi-tank to reach the load.
Rich, ag6k

...
This can't happen if the amplifier is sitting idle,


  so electrons can Not be knocked loose from a Mo grid when there is HV present and the amp is in standby?

 
Quote
it can't even happen in a properly designed amplifier[/quote

 chortle.  This is what one of our "recognized amplifier experts" told me about VHF parasites but he could not explain what was proper and what was not. 

Quote
There isn't going to be enough electrons dislodged by some cosmic ray, or high energy photon

  why not?

.
Quote
If this could even happen, how do you think we would have made it to the moon and back as many times as we did?

  Because there were no whopper solar flares or any gamma-ray bursts from a supernova during any moon mission.

Quote
There is nowhere on the net I can find any documentation for this ever occurring.
Nobody has written any papers on this.

Your Geiger tube does it because there is a large bias on the electrodes

  My Geiger-Muller tube runs on 900vdc.  Said 4-1000A runs on 5000vdc.

Quote
and the gas inside is at a rather low pressure.

  can electrons only be knocked loose from gasses?
Rich, ag6k
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AF6LJ
Member

Posts: 2




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« Reply #98 on: October 31, 2011, 09:19:01 PM »

Quote
AF6LJ
Susan
   
RE: Background Radiation - Could It Be a Vexation ?
« Reply #94 on: Today at 03:06:53 PM »
   
Reply with quoteQuote
Quote from: AG6K on Today at 02:34:59 PM
Quote
2E0CHE
   
RE: Background Radiation - Could It Be a Vexation ?
« Reply #92 on: Today at 01:56:44 PM »
   
But nowhere near enough to be in any way significant without gas to provide for avalanche breakdown.... ... ... ..

  One more time:  Hello,   There is no breakdown or arc inside the tube.  The tube briefly conducts, rings the anode-circuit's parasitic VHF resonance, which makes a damped wave VHF signal - which is than amplified and re-amplified until things largely run amok because VHF energy can not pass through the LowPass Pi-tank to reach the load.
Rich, ag6k

...
This can't happen if the amplifier is sitting idle,


  so electrons can Not be knocked loose from a Mo grid when there is HV present and the amp is in standby?

Not by such a small and low energy source.
Sorry Rich it's not happening, it's not happening with a copper anode and it's certainly not happening with glass or ceramic insulator material.
If it ever does you and I won't be alive to see it.


From where did you learn physics?
 
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AG6K
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Posts: 1




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« Reply #99 on: November 01, 2011, 02:09:37 AM »

Quote
Quote from: AG6K on Yesterday at 05:37:21 PM
Quote
AF6LJ
Susan
   
RE: Background Radiation - Could It Be a Vexation ?
« Reply #94 on: Today at 03:06:53 PM »
   
Reply with quoteQuote
Quote from: AG6K on Today at 02:34:59 PM
Quote
2E0CHE
   
RE: Background Radiation - Could It Be a Vexation ?
« Reply #92 on: Today at 01:56:44 PM »
   
Quote
But nowhere near enough to be in any way significant without gas to provide for avalanche breakdown.... ... ... ..

Quote
  One more time:  Hello,   There is no breakdown or arc inside the tube.  The tube briefly conducts, rings the anode-circuit's parasitic VHF resonance, which makes a damped wave VHF signal - which is than amplified and re-amplified until things largely run amok because VHF energy can not pass through the LowPass Pi-tank to reach the load.
Rich, ag6k
...
Quote
This can't happen if the amplifier is sitting idle,


Quote
  so electrons can Not be knocked loose from a Mo grid when there is HV present and the amp is in standby?


Quote
Not by such a small and low energy source.

  what is the source Susan?

Quote
Sorry Rich it's not happening, it's not happening with a copper anode and it's certainly not happening with glass or ceramic insulator material.

  so the electrons in some elements are stuck better than the electrons in other elements?  Hmmmm.  Very interesting.

Quote
If it ever does you and I won't be alive to see it.

Quote
From where did you learn physics?

  When running low on ammo, attack the CV. 

cheers Susan
Rich, ag6k
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G3RZP
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Posts: 1321




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« Reply #100 on: November 01, 2011, 04:52:06 AM »

If the tube is biased off, how can it have any gain to amplify the VHF signal pulse? Ergo, unless the pulse has suffisient energy to cause the damage, the tube can't amplify enough to do it.
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AF6LJ
Member

Posts: 2




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« Reply #101 on: November 01, 2011, 06:21:15 AM »

If the tube is biased off, how can it have any gain to amplify the VHF signal pulse? Ergo, unless the pulse has suffisient energy to cause the damage, the tube can't amplify enough to do it.

I think what Rich is failing to understand is there must be a complete circuit for current to flow regardless of energy of the external source (photons, gamma rays X-Rays etc.).

Question for Rich;
How much energy is required to knock electrons loose from Glass?
How much energy is needed to knock electrons loose from Copper?
And finally have you ever seen glass ionize from cosmic rays or any other high energy radiation?

Lastly;
I was not attacking your CV I just asked a question, Please don't take it personally. My own CV isn't anything to brag about. I'll freely admit my knowledge of high energy physics comes from books and simplified discussions on the subject.

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AG6K
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« Reply #102 on: November 01, 2011, 07:46:40 AM »


RE: Background Radiation - Could It Be a Vexation ?
« Reply #100 on: Today at 04:52:06 AM »
   
Quote
Reply with quoteQuote
If the tube is biased off, how can it have any gain to amplify the VHF signal pulse? Ergo, unless the pulse has suffisient energy to cause the damage, the tube can't amplify enough to do it.

  No current is required to overcome the cutoff bias-V and cause anode-I to flow.  When anode-I flows, thanks to the feedback-C, the tube can amplify and re-amplify the damped-wave signal . When the tube conducts, the cathode bias relay contacts can arc, major current can then flow, followed by the fireworks show.
Rich, ag6k   
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M0HCN
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Posts: 566




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« Reply #103 on: November 01, 2011, 07:54:17 AM »

Well you can knock electrons loose from all those materials, the key phrase is 'work function', but so what, a few dozen, or even a few hundred electrons is an utterly negligible amount of current in this context, and even when accelerated across a few KV, does not amount to a meaningful amount of energy compared to that stored in the tank circuit in normal operation (or even that in the VHF resonance in normal operation).

The grid has capacitance, ergo current MUST flow to change the grid voltage, dV=dQ/C. I have already demonstrated that the grid capacitance is large enough to make the charge on any reasonable number of photoelectrons that could be freed utterly irrelevant.

Further in standby the tube is biased well off, the grid would have to become quite a lot more positive to allow gain, and would have to stay there for long enough for oscillation to build up. If the amp was unstable at VHF it would show in normal transmit mode way before the instability got sufficiently severe (I don't think it could) to show with the tube based off.

I am out of here.

73 Dan.
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G3RZP
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Posts: 1321




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« Reply #104 on: November 01, 2011, 09:07:10 AM »

So we have a very small current that now manages to get enough energy to turn the tube on and produce an arc?

Sorry, Rich, this is mere fantasy. The evidence just doesn't hold up.
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