> >All the stuff you and Rich blame on "parasitics" is mostly arcs due
> >to outgassing and seal leakage. ...
>
> Funny thing that the alleged Rauchian gas disappears by the time that the
> kaput tubes are removed from the amplifier and tested with a
> high-potential tester.
Not a funny thing at all, common sense.
In the publication "Getters and their Function in Vacuum Tube
Manufacture", arcs are listed in methods of gettering a tube.
Also, not all arcs are gas. Some are from what are referred to as
Barnacles, high spots on the grid or anode. An arcs usually removes
Barnacles.
> I tested a pair of kaput 3-500Zs for Rod, W7OM,
> this morning. Both appeared to have been damaged by VHF parasitic
> oscillations. However, the vacuums tested good. At least one of the two
> appeared to have a bent filament--like the one on page 15 in the Sept.
> 1990 *QST* article "Parasitics Revisited". .
Like asking Dr. K if the patient needed to commit suicide, isn't it?
;-)
73, Tom W8JI
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