On 5/30/2012 12:42 PM, Channel Jumper wrote:
'Jeff Liebermann[_2_ Wrote:
;791197']On Tue, 29 May 2012 19:12:00 +0200, "Szczepan Bialek"
wrote:
My HT antenna isn't grounded. Neither are any of the dipoles on my
roof. I presume you're suggesting that they don't work.
--
With a Hand Held Radio - the person holding the transceiver is the
ground plane. Because the human body is comprised mainly of water, it
acts like the missing half of the antenna.
Radio waves in front of the person is radiated, radio waves behind the
person is blocked to a small extent because of the water in the persons
body.
This is the reason why Rabbit Ears antenna's do not work in concrete
apartment buildings with people moving around the room.
The person who is walking around blocks some of the reception -
especially in the higher frequency ranges because anything one or more
wavelengths in size can and will block a signal.
Not quite right, since you don't have to actually "block" the signal for
it to happen, but Mr. Blaupunkt wouldn't have a clue anyway. It's more
about the whole wavefront, amplitude of the parts of same, phase, and
interaction with the surrounding conductive and absorptive environment.
Some of which can be alive, filled with salt water, and move.
tom
K0TAR