Rich, see my questions below:
----------
From: measures[SMTP:2@vc.net]
Sent: Sunday, March 05, 2000 3:11 PM
To: Michael Tope; AMPS; 'W8JI@contesting.com'
Subject: RE: [AMPS] Network analysis of suppressors
>>
>> Borrow a geiger counter, Mr. Rauch, and tune in on what's happening on the
>> upper frequencies. Be not surprised if you occasionally encounter some
>> humungous signals.
>
>Rich or Tom, please forgive me if I misrepresent any of your
>claims as I haven't been following this debate very closely
>and hence am not fully versed in the details of your respective
>positions. Regarding the idea that radiation single events can
>cause significant current to flow in a high power vacuum tube,
>this seems unlikely to me.
As it first did to me, Mike. My guess is that a photon strikes an atom,
knocking loose a current carrier/electron, thereby causingthe tube to
briefly conduct. This causes several kV to appear across the bias
contacts, which arc. The contacts form a metal vapour arc. Since the
voltage drop across such an arc is low, the amplifier tube switches out
of cutoff bias and an event could take place.
cheers
Rich, a couple of questions?
1. Are my assumptions about the operating conditions
in the above scenario correct - B+ = ON, Filament = ON,
BIAS = CUTOFF?
2. From where in the tube does the free carrier (electron)
emanate - the surface of the cathode, the control grid,
the anode, residual gas in tube?
3. What is the direction of the current flow that is created
by the free carriers - cathode to grid, cathode to anode, grid
to anode?
4. How do a few electrons create a potential change of several
thousand volts across the bias relay contacts? Since V = Q/C,
seems like it would take many electrons to raise the voltage
across the bias relay contacts to a few thousand volts (the
charge on an electron is around 10E-19 coulombs). How many
electrons are we talking? Is the bandgap energy involved in the
carrier release consistent with radiation events of probable
magnitude (or are we talking about real "big bang" energies?)
Thanks,
Mike, W4EF.............
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