Last night provided my first good test of my phased verticals with the
ANC-4 as a phasing box. The two verticals are 30 meters apart, about
the same size (27 and 30 meters) and with elevated radials. One of
them is my transmit antenna.
The flexibility of the system (steerable nulls) paid off for my QSO
with UA0KAG. KH6CC was on the same frequency and was much louder than
KAG. Not sure who Jack was working - maybe he was off frequency some.
At any rate, I was able to null Jack out so that his signal was "gone"
and I could hear UA0KAG (who was calling CQ DX) without any QRM.
For the European signals, I could get some improvement with the system
over one vertical. In some cases, I was nulling out local QRM which
was triggering my noise blanker (had a little line noise at times).
Other times I found I could get some improvement by nulling out the
station, then pressing the switch that seems to invert the reference
antenna by 180 degrees.
Certainly the nulls are more significant than trying to peak a
station. Since I am defeating the mutual coupling between the
antennas, I am not realizing any gain. I hope to work out a passive
phasing circuit soon so I can get some gain. It would be nice to have
it as adjustable as the ANC-4 is.
The ANC-4 sure makes for an easy way to get some directivity. It
should be possible to use it with most any other receiving antenna you
have to get some directivity (like an 80 meter dipole?).
73 Tree N6TR
tree@contesting.com
PS: This system was the only RX antenna I used last night.
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