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December 23rd 03, 05:00 PM

(Richard Harrison) wrote in message ...
Art, KB9MZ wrote:
"---he has seen commercially were pock marked because of flashovers."

True. It mystified me that lightning preferred the Faraday screen to the
made for the purpose arc-gap across the base insulator. It may result
from impedance discontinuity. The surge impedance of the tower depends
on how skinny it is. The rigid rod connecting a tower to the "dog house"
network is at a certain height above the earth which gives the rod a Zo
as a single conductor transmission line, then this line connects with an
snip

..

The bandwidth of standing wave antennas may be small when compared with
the frequency range allocated for an amateur band, but as compared with
the intermediate frequency passband of the receiver, the antenna
bandwidth is likely large. The Q of the antenna is lowered by radiation
resistance which is the antenna`s end product.

Hold it right there please Richard,

My antenna is more than just a radiator it is a 'band pass filter'
purposefully made that way to REJECT unwanted signals at the onset !
The normal antenna supplies everything to the radio whether you like
it or not. Not only that, it AMPLIFIES it before you supply the
filtering effect of a crystal.
Even tho the crystal narrow the band pass for listening purposes the
unwanted
signals have already entered the radio and contributed to the noise
floor.
I realise that most people separate the function of the antenna from
the receiver and thus do not consider it in exactly the same way.
By the way my screen was a wire tray so yesterday I cut away the
horizontal
struts. One swallow doesn't make a summer but the atmospheric noise
was down a full S unit from yesterday even tho it was raining and a
snow front moving in.
Things like this fits right in with my antenna design purposes which
is to make use of networks
Best Regards
Art

Best regards, Richard Harrison, KB5WZI