If you want to null out power line noise, the loop
circumference needs to be something like 50 feet
maximum, and the nulling is better with smaller
loops. A small loop needs to be tuned to get reasonable
sensitivity. A non-resonant loop might not over
come the receiver noise. Adding a preamp may or may
not work because of the noise floor in the preamp.
The preamp may overload on BCB signals; tuning the
loop makes it a cheap BCB reject filter. So called
"shielding" makes the loop implementation much less
critical, but is not fundamentally a game changer.
OTOH, there is no disadvantage associated with shielding.
You may want to read my NCJ article on loop antennas
in the Sept/Oct 2009 issue. If you don't have this
issue, a scan is posted in the "files" section of
the Yahoo group "loopantennas".
Rick N6RK
rick darwicki wrote:
> Hi all,
>
> With high local line noise, is a TUNED LOOP or non-resonant RX loop a better
> option?
>
> I've seen blogs that shielding a loop really doesn't do much.
>
> Comments?
>
>
> Rick, N6PE
> ===============================================================
> Remember, Some things are not worth doing well
> _______________________________________________
> 160 meters is a serious band, it should be treated with respect. - TF4M
>
>
_______________________________________________
160 meters is a serious band, it should be treated with respect. - TF4M
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