This is from the ARRL Antenna Book:
Practical Suggestions For Vertical Ground Systems
At least 16 radials should be used if at all possible.
Experimental measurements and calculations show that with
this number, the loss resistance decreases the antenna efficiency
by 30% to 50% for a 0.25 wavelength vertical, depending on
soil characteristics. In general, a large number of radials (even
though some or all of them must be short) is preferable to a
few long radials for a vertical antenna mounted on the ground.
The conductor size is relatively unimportant as mentioned
before: #12 to #22 copper wire is suitable.
a.. If you install only 16 radials they
need not be very long - 0.1 lambda is sufficient.
b.. If you have the wire, the space and the patience to lay
down 120 radials (optimal configuration), they should
be 0.4 lambda long. This radial system will gain about 3 dB
over the 16-radial case.
c.. If you install 36 radials that are 0.15 lambda long, you will
lose 1.5 dB compared to optimal configuration.
Hope this helps!
73 -- Larry -- W1DYJ
----- Original Message -----
To: "K2VI" <firstname.lastname@example.org>
Sent: Thursday, January 13, 2011 2:48 PM
Subject: Re: [TowerTalk] ground radial project
> As many radials as can be put down and as long as possible.
> "Resonant" is not important.
> Quoting K2VI <email@example.com>:
>> Ok, thanks to all who responded to my last post. really appreciate
>> all the help. I considered the ground bus system but didn't want to
>> bury the aluminum due to it disintegrating in 5 years and above
>> ground how could it be secured without it shifting. So i just went
>> ahead and ordered the DX engineering stainless plate. It U bolts
>> right to the post. I just bought 26,000 feet of # 14 stranded
>> insulated copper wire at a govt surplus bussiness in norfolk va. I
>> paid 615.00. I know i will never use all of it in a lifetime but who
>> knows. For that price i had to jump on it. So the question is on my
>> 43' vertical how many radials would you reccomend before it's a
>> waste of time and should i make them longer than the antenna. I can
>> run some as long as 55' and some as short as 25'. Im thinking 25'
>> would be ineffective. Any ideas. thanks in advance.
>> tony k2vi
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