Cecil Moore wrote:
Jim Kelley wrote:

Consider the nature of dielectric materials. I could be wrong, but I
bet if you stuck a negative oxygen ion on the outside of a jacketed
conductor, you could make the conductor inside think you had put an
electron directly on it.


The question is whether the electron stays on the insulation
or migrates through it to the conductor.

Actually, the question is whether or not one can hear the resulting
noise.

The size of the charge Vs the dielectric determines how
much of the charge actually reaches the conductor.

Perhaps you mean the amount of charge Vs. the dielectric determine the
voltage.

When
I went from bare wire to 600v insulation, my precipitation
static problems decreased considerably. Then when I went to
1000v insulation and a full wave loop, most of my precipitation
static problems disappeared.

I see your point. The poorer the dielectric and the greater it's
thickness, the lower the induced voltage. There should be some
effect, yes. What'd you use, 20 meters of CRT anode wire or spark
plug wire? :-) The point with which Tom seemed to take issue was the
implication that an antenna with low DC resistance would have lower
precipitation static noise. I also disagree with that notion.

The worst case of precipitation static seems to be for
airplane antennas. Insulation is the recommended cure
although folding is also mentioned. Please do a web
search for "precipitation static" and see for yourself.

http://www.atis.org/tg2k/_precipitation_static.html

I'm glad we agree on the definitions. In one of your previous
references I noted the term precipitation static used (incorrectly) to
describe the noise associated with static discharge. This is a
distinction I attempted to point out in my earlier post.
Precipitation, among other things, can cause charge to accumulate on
objects which are insulated from ground. This accumulation can
continue to increase until breakdown occurs, causing a spark and a
noise which is big enough to knock down the receiver AGC for a few
seconds (or worse). Precipitation static is the noise which is
apparent when a relatively high flux of ions impinges upon an antenna.
Low DC impedance antennas won't accumulate large amounts of charge
or generate a static discharge, but they are nevertheless sensitive to
the static noise just as any other antenna would be. In other words,
you and Tom W8JI are both right - you just don't know why. ;-)

Did you see the article in Harper's magazine on W6AM? Pretty neat.
Even that article mentioned precipitation static.

73, ac6xg