If you don't mind the unsightly effect then I recommend as many as
possible corrugated sheets around the base of the vertical. I use them
over a full set of 120 x .41 lambda radials on 40m - they make a big
difference.
They also stop the rabbits from biting thru the radial wires - in
September I noticed that a family of a rare species of toad had nested
under one of the sheets (now marked with a white cross to remind me not to
tread on it!).
73 Cris
GM4FAM
> Yes, when I had inquired on the Towertalk reflector several months ago
> regarding the use of chicken wire, someone responded privately and said
> that BC stations had abandoned wire mesh screens many years ago because
> of undesirable eddy currents. The eddy currents were thought to oppose
> the return currents and actually made the system less efficient. The
> writer referenced two engineering books from th 50s, and I suspect the
> book you mention was one of them.
>
> 73, Joe
> K2XX
>
> Thomas F. Giella NZ4O wrote:
>> BTW I have a 574 page e-book published in 1952 called Radio Antenna
>> Engineering. It covers LF/MF and HF antennas. I downloaded it for free
>> at
>> http://www.lulu.com/content/159004. It says that putting down chicken
>> wire
>> type mesh under the vertical is not good due to some sort of RF
>> cancellation.
>>
>> 73 & GUD DX,
>> Thomas F. Giella, NZ4O
>> Lakeland, FL, USA
>> nz4o@arrl.net
>>
>>
>>
> _______________________________________________
> 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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