>
>Rich wrote:
>
><italic><FontFamily><param>Courier</param>> >Arcs inside the tube do make
>a large bang if
>the amplifier does not have
>
>> >enough ESR in the anode system.
>
?? I did not write this, Mr. Rauch.
>
>> When a 2000pF vacuum variable arcs, it makes a
>> barely audible sound.
>
>
></italic>What an amazingly poor analogy. A vacuum
>variable is generally in a resonant circuit with very little reserve
>energy. When it arcs, the
>circuit is detuned and energy flow immediately
>stops.
>
The vac capacitor was connected to a high-pot. . When the capacitor
arced, 5100v discharged through less than 0.5- ohm of ESR. A tink was
heard, In my opinion, arcs in open air can make stentorian noises. Arcs
in a vacuum are a whole nuther ballgame because there is no sound
conducting medium surrounding the arc. .
>
>A power grid tube, on the other hand, almost
>always connects
>
>across a dc supply with considerable stored
>energy and other
>
>components in the path.
>
>
>When it arcs, it has to pull the supply with its
>high stored energy to
>
>ground and does so through may components that
>are connected
>
>in series with the path.
>
>
>When you have some time, do the following
>experiment. It may
>
>help you understand the problem.
>
>
>Charge a 40 mFd capacitor to 4000 volts and
>discharge it with a
>
>vacuum relay. Listen to the noise.
>
>
>Now do the same with the vacuum relay across a
>4000 volt
>
>charged 1000 pF vacuum capacitor. Listen to the
>noise.
>
>
>For an added measure of realism, throw a RF
>choke in series with
>
>both when doing the test.
>
>
>You will hear a large difference in noise.
>Amazingly enough, no
>
>parasitic oscillation is
>required!!!<color><param>0100,0100,0100</param><FontFamily><param>Arial</p
>>aram
>
><nofill>
Mr. Rauch -- your e-mailer app. appears to be having parasites.
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