[Antennas] ground mounted vertical radials question

[Charles Greene]

David,

The best approach is to go for more radials on the order of 0.1 
wavelength rather than less radials that are longer.   I have a 
Hustler 6BTV and I put 2 radials for each band about a 1/4 wave 
length each; however, that was several years ago and I'm smarter 
now.  So if a radial is 0.1 wavelength on 80, it is 0.2 wavelength on 
40, 0.4 wavelength on 20 and so on so it is an effective length on 
all bands.  The reason for this is that current in the ground radial 
drops off over 0.1 wavelength so making the  wire longer  is not 
necessary, but the longer wire does not degrade the effect of the 
radial, so the longer wires are still an effective length.  You would 
think 1/2 wavelength would not be a good length as it would ofer a 
high impedance at the antenna, but looking at the current that is not 
the case.  Using more than 16 radials does not help much.  In other 
words, 32 radials marginally better than 16, but not twice as good.


73,  Chas W1CG

At 12:37 AM 11/11/2006, David Ashworth wrote:
>Hello to all.  Will be installing a Hustler 5BTV vertical on the ground, up
>in the country where there is no problem with people tripping over radials.
>The radials will NOT be buried.  They will be placed upon the ground.  Been
>reading my reference material on radials, but would like to hear from
>operators that have been there/done that.  The lowest band will be 80 meters
>and the highest 10 meters.   Hustler recommends at least two radials per
>band.  Then, been reading W2FMI's book about short verticals.  Think he was
>happy with about 40 radials.  Am I on the right track, the more radials, the
>better, up to a certain point?  The soil there is very dry unless it has
>been raining.  As soon as the sun comes out, there goes the moisture content
>of the soil.  So, would it be better to spread, say 40 radials at 1/8
>wavelength, or maybe 20 at 1/4 wavelength?  Would you spread some for just
>80, or do a combination of the different bands?  If this was salt water, bet
>you could throw a coat hanger in there, but it is not.  Any good ideas?  I
>am leaning towards less radials and longer radials, but experience is the
>best teacher.  Thank you for your comments/recommendations, Dave, NC6P.
>
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