I asked:
> >Please Rich, enlighten me on how the shiny surface means it was
> >a parasitic, and the bubbled surface means it was HF heating.
Rich replied:
> I did not say that a shiny surface means it was a parasitic oscillation.
> A shiny surface indicates that the outside of the resistor did not get
> hot. A bubbled surface indicates that the outside of the resistor was hot
> for an extended period. A >3x increase in R indicates that the insides
> were severely damaged Add a shiny case, and the >3x change suggest that
> the change probably happened quickly. . .
OK.
You say a sharp pulse of VHF current heats the resistor from the
inside out, while a longer HF current heats the resistor and
severely damages the outside.
That seems to disagree with what you say about other conductors.
For example you claim gold coatings on grids can only be
damaged by VHF parasitics, and not by dc or lower frequency
currents.
How are grids damaged from the outside in (as you have claimed
many times) while resistors are damaged from the inside out by
short bursts of VHF energy? How can the resistor get that hot
inside when the saturated anode current is only about ten
amperes, the duty cycle is in nanoseconds, and the resistance is
under 100 ohms?
This almost sounds like your theory that photons arriving from outer
space can make amplifiers on standby explode because the
photons hit the amplifier so hard they make the standby relay arc,
and the arcing relay starts a parasitic in what is an otherwise
stable amplifier that is just sitting there on standby!
I think the photon theory outdoes the reverse skin effect theory
shiny resistor theory.
73, Tom W8JI
w8ji@contesting.com
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