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Old September 11th 03, 04:21 PM
Richard Harrison
 
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Mark Keith wrote:
"As far as noise, if the dipole and loop are both horizontal, there
should be little if any difference in noise received, unless the pattern
of the particular antenna favors the noise source."

I wrote that the loop was small at lower frequenciues such as those used
with power mains and BC band transmitters. This can be equalized by an
r-f choke across the receiver input to short out the low-frequency
interference. A folded dipole or loop antenna doesn`t need a choke.
Their configurations provide a short at low frequencies.

I noticed the hum pickup of car radios using untuned r-f anmplifiers
back in the 1940`s. They had no low-frequency, low-impedance path for
noise intercepted by the conventional whip antenna. Radios with a
conventional antenna coil had bo antenna hum problem.

Best regards, Richard Harrison, KB5WZI