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Re: 435 drooping dipole



>Wayne replies:
>
>An "inverted vee" is not a good antenna for satellite use on the 2m and 70cm bands.  The gain pattern is not well suited for satellite reception when the antenna is several wavelengths above the ground.  It has very large "deaf areas" in the sky, mostly at high elevations.  For 2m and 70cm, a ground plane antenna is very easy to build and gives better performance for satellite use because it receives signals from both high and low elevations.
>
>Ground reflection does cause an inverted vee antenna to have a good hemispheric gain pattern when the feedpoint is 3/8 wavelength above the ground (or above a ground plane).  With the feedpoint 12 feet above the ground, a 10m inverted vee is a good antenna for receiving the downlink of RS-12/13.
>
>Wayne Estes W9AE
>Mundelein, IL, USA

I don't know about that.  I had pretty good luck on the Fuji-Oscar birds
using an inverted vee on 70cm.  

At 25 feet, NEC shows a multitude of nulls and peaks in elevation, but
it's fairly uniform in azimuth.   In practice, it seemed to work OK,
however, mine was about 15 feet above the deck of a steel ship, perhaps
adding a groundplane effect.

 

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