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Re: Comments on UO-14

na9d@mindspring.com writes:

> > I found it illuminating that with a 50 W mobile rig and
>  > a mag-mounted vertical dipole antenna on 2 m, I could not even get 1 
> contact
>  > in with the bird over the eastern US.
>  If you have anything greater than a quarter wave antenna, most of the
>  radiation is in the horizontal direction.  The pattern falls off rapidly as
>  your angle of elevation gets higher.  That's why you were able to hear the
>  bird near the end of the pass and also on the more western pass where (I
>  assume) the angle of the satellite was lower in the sky to you.

A 1/2 wl vertical antenna (e.g., a dipole)  has an almost identical elevation 
pattern to a 1/4 wl GP.  Any distinction is the patterns is meaningless in 
this context.  I did not mean to imply I could not hear the bird.  In fact, I 
had 100 % copy from horizon to horizon using a hand-held 3-element beam.  My 
observations were on the differing behaviors between the two coasts.  What I 
didn't say was that I never had this kind of problem with AO-27.  I guess it 
only goes to prove how immensely popular the easy-to-hear FM birds are.  If 
you are interested in the pattern for the vertical antenna, please see the 
link below and select "2m Mobile Vertical":


Jerry, K5OE

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