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Old January 12th 04, 05:04 PM
Richard Harrison
 
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Ralph Mowery wrote:
"The 1/4 wave vertical at about 16 or 20 inches will tend to put much of
the signal towards the sky like a round ball would look laying in the
water."

The mental image Ralph`s statement creates in my mind is mistaken. The
1/4-wave vertical antenna over a reflecting plane has a pronounced null
at its tip. The pattern is no hemisphere.

See Fig 3 on page 3-5 of the 19th edition of the ARRL Antenna Book for
the vertical radiation pattern of a 1/4-wave vertical antenna over
earth. Over a ground plane antenna at any elevation, the pattern is
similar, that is, there is a pronounced null at its tip.

Best regards, Richard Harrison, KB5WZI