> > Ya know joe, I've got a box full of DF Bearings that
> > I got when we took down a radar site in Maine... maybe
> > I could use them to rotate my MMA Vertical to change
> > the pattern... hmmm
>
I suspect that you may be unsuccessful with this application. Old Timers
will all agree that the best DF Bearings are always made with the null of
the antenna. Given the way the DOD used to spend money, you probably have
a very high quality set of bearings. Unfortunately, that means that if you
tried them with your MMA Vertical, you would probably find a sharp null in
the pattern at precisely the direction in which it is pointed. Although I
would have to work out the math on this one, I suspect that your bearings
were all made with horizontal polarization, so the maximum null in a cross
polarized application would probably be -20 db. This is clearly an
improvement, but I still suspect you would be unhappy with the resulting
gain dBd (gain over dummy load).
Nevertheless, do not let me discourage you from experimenting. Please
report back to the list with your results.
Mike
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