----------
>Från: "sm5ki" <sm5ki@algonet.se>
>Till: measures <2@vc.net> , Tom Rauch <W8JI@contesting.com> , AMPS
<amps@contesting.com>
>Ämne: SV: [AMPS] Re: Poor Science
>Datum: mån 6 mar 2000 20.38
>
>What remains in this endless discussion is, that someone opens those broken
>tubes and inspects them to see what happened? Who has the will and the
>knowledge?
>
>de Hans
>----------
>>Från: measures <2@vc.net>
>>Till: "Tom Rauch" <W8JI@contesting.com>, "AMPS" <amps@contesting.com>
>>Ämne: Re: [AMPS] Re: Poor Science
>>Datum: mån 6 mar 2000 14.55
>>
>
>>
>>>
>>>> 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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>>
>>
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