>
>> You asked for an example ... I gave you one that repeated itself.
>> I am curious as to why I had to replace two 3-500z"s. The way the
>> amplifier made a huge grunt and tripped the breaker ... with the 3-500Z's
>> shorting and pieces of either filament or grid being loose in the tube
>> tells me something violent happened. And since it occurred while moving
>> the top cover in relation to the tubes and tank circuit, leads me to
>> believe it was an oscillation. What is your expert explanation please ?
>
>Don't know. There could be several causes.
>
>Isn't the Henry interlocked? Did you accidentally short the HV to
>ground?
? Zzzzzzz -- shorting the HV to gnd could not cause this. .
>
>......
>> >>2.) What type of tubes.
>>
>> HELLO !!! Already stated.
>
>DUHHH!!! What manufacturer. Do you understand that better?
>
? Tube type means something rather different than Manufacturer, Mr.
Rauch. As one of our ''recognized amplifier experts'', I should think
that you would be aware of this.
>> >>3.) Why don't the photons generated in normal operation cause the
>> >>same problem?
>>
>> You asking me ?
>
>Yes. I generally like to know if a theory is even remotely
>reasonable before believing it. The "photon theory" is rubbish,
>unless photons in California are different than photons in the rest of
>the Universe.
>
>> >>4.) Why don't photons in gas-filled tubes specifically designed to
>> >>detect photons have even modest amounts of current?
>>
>> >>5.) Why do hundreds of other amplifiers without covers not fail?
>>
>> ??? Has nothing to do with what I stated.
>
>It has everything to do with what you stated, because you offered
>your "story" in support of Measure's claim that a photon can cause
>a tube to suddenly draw so much current it with cause the relay to
>arc and put the PA in an operate position.
>
>If that was true, why are radiation detectors optimized for this
>purpose filled with gas, and why do they have peak currents
>millions of times less than the current in a power grid vacuum tube?
>
Because a nearly ionized gas makes a more sensitive radiation detector.
With the typical geiger tube, one gets a hit every second or so. With
transmitting tubes, one may have a big bang every 8 years or so.
>If that made sense, why do many or all amplifiers with tube arc
>when exposed to room light? Why can't we use 3-500Z's as
>photocells?
smoke
>
>> >>6.) Since the saturated current of a 3-500Z is about 10 amperes or so
>> >>(that's all the filament can "give up", even if you hold the anode and
>> >>grid at 3000 volts positive), how does the oscillation cause enough
>> >>current to shatter the filament or grid?
>>
>> I would really like to know what shattered mine.
>
>Well one thing we do know, it can't be anode current through any
>kind of emission.
You talk about about recurrent peak emission. A one-shot event might be
a whole nuther ballgame.
>
>Maybe you simply moved the PA, and the filaments were ready to
>break.
Grasping at straws. Playing for time. // As I understand it, the bits
of metal were from the grid cage. The filament per se was intact,
although it was bent laterally.
>
>> >>7.) If the tube could supply that much current, how does it get that
>> >>current so fast through the high surge impedance of the path from the
>> >>energy storage area (power supply) into the tube?
>>
>> Good question ... but in this case as I recall there is no current
>> limiting in the B+ or B- of the HV supply.
>
>Use logic. These alleged "gremlins" are all VHF parasitics.
>
>The reactance of the anode choke and even the leads inside the
>PA would severely limit the current.
There is very little ESR in a Henry 2K-4. The anode supply is one of the
stiffest known. There is no glitch R. The filter caps are paralleled
oil filled type.
>The only major current that
>could flow, assuming Henry didn't design-in enough ESR to limit
>surge would be at dc and through an arc that actually sustained
>high levels of conduction for a long period.
>
The big bang suggests a short period.
>I think someone has a parasitic fetish.
>
Mr. Rauch's attempt to introduce a sexual angle into this entangle is
quite interesting.
>> >>If you have no explanation other than blind faith, then I can accept
>> >>that and respect it. I never argue religion.
>>
>> I have no explanation, only suspect.
>
>OK, then I can accept the fact you have no idea what caused the
>problem. Only a guess.
>
Perhaps disassembly of the parasitic suppressors and measuring the
R-supps might help to make a better guess?
W7MOI, the Old Timer who told me to ''Always Measure R-supp'', and to not
go by appearances, happened to own a 2K-4 that did the big-bang thing and
grid-fil. shorted a tube.
cheers, Tom
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