"Cecil Moore" wrote in message
. ..
chuck wrote:
What is elusive is how the charges get changed into a detectable signal.

By definition, corona requires ionization of the air
which requires a certain current through the air, i.e.
at least a small arc. The question is, can p-static
exist and be heard below the corona threshold?

corona is not an 'arc', an arc is normally between two conductors. corona
is a local cascade breakdown in air as electrons are accelerated enough so
that when they colide with another molecule of the air they can knock off
more electrons. That is why there is a threshold voltage for corona
inception, below a given field strength the electrons can't gain enough
energy to sustain the breakdown. note that the shape of the conductor is
very important in this process also, a blunt smooth surface will produce
smaller fields and have a higher inception voltage than a sharp point
because the field gets concentrated more around the point and thus requires
a lower voltage to start corona breakdown.

What can we conclude by applying the
principle of antenna transmit/receive reciprocity?

in this case, nothing. the tx problem was because the rf voltage at the
antenna tips was high enough to cause corona on a massive scale. rf voltage
on a receiving antenna is miniscule and so can not be the source of
corona... this means other sources, not related to rf and the intended use
of the structure as an antenna, are the cause.