RadioBanter - View Single Post

June 11th 06, 04:59 PM posted to rec.radio.amateur.antenna

wrote:
People actually seem to think the little particles voving through the
air charge the antenna to a different potential than the air around the
antenna, and that a "dc" path to earth or "dc" path around an element
somehow magically stops RF noise.

Let's say we have the following bare-wire dipole system
link coupled to the receiver (in fixed font).

|
| dipole element A link coupled
| -////-
+--------------------------------------------------///////--+
|
+-----------------------------------------------------------+
|
| dipole element B
|

Let's assume one highly charged particle hits dipole element
A and transfers half of its charge. Element A will then have
an excess charge one half of which will migrate through the
link while equalizing the charge between element A and element
B. That charge migration/equalization no doubt results in an
RF noise pulse.

This experiment can easily be performed by anyone.
Rub one's leather soles on a wool carpet, touch one side of
the dipole, and listen for noise in the receiver. Guaranteed,
it will be there.

Now multiply the above by millions of charged particles
randomly encountering the bare-wire dipole. The charge on
each side of the dipole will never be exactly equal. Thus,
continuous broad-band noise will be continuously transferred
through the link as long as the particles are transferring
charge to the antenna. That's what some hams are hearing
during dry-air dust and snow conditions. Some have even reported
being able to hear individual particle collisions from large
snowflakes.
--
73, Cecil http://www.qsl.net/w5dxp