At 07:45 PM 12/15/97 +0000, Andy Cook G4PIQ wrote:
some text snipped:
>
>It's seems likely that arrival angles are not static over even short
>periods of time - listening to a signal with QSB on a low and a high
>antenna often shows the QSB to be out of phase between the two.
--another snip--
>On a similar topic, the folklore of the low bands is that there are
>often nights when the verticals are good and nights when the horizontal
>antennas are good. I've always put this down to differing arrival angles
>between those nights rather than anything fundamental about the arrival
>polarization. Anyone care to comment?
This phenomena is exactly why Yaesu offers the ability to
have the separate rcv ant input for the "sub" rcvr. The
suggested method in the FT-1000 manual is to feed an input
from a vertical (or 2nd beam at a different height) into the
BPF-1 antenna terminal of the sub rcvr. See pg 31 of the
FT-1000 manual, "Antenna Diversity Reception". The manual
author goes on to write, "..the vast potential for
optimizing reception of different signals using diversity
recetion with the FT-1000 is largely unexplored"
I use inverted V's into the BPF-1, and then the V-beams on
the lower bands (30 on down) or the beam from 17 M on up.
Very interesting results.
73, Jim, KH7M
On the Garden Island of Kauai
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