Wow, I didn't read the reflector (I don't get the emails, just visit the site)
for a few days and it seems there is a lively discussion going on! Thank you
all who took the time to contribute.
So let me step back and share in more depth my thinking, which by the way is
heavily influenced by Low Band DXing:
1) A fan dipole is a very attractive option as simplifies my tower. It will get
way too messy if I have individual dipoles. Note, however, that I plan on
having the wires parallel to each other as I want to space them 4' from each
other to simplify tuning. Yes, takes two support poles for each end, but space
is not an issue.
2) To deal with the wide range of takeoff angles, I am considering two options:
a) configure the fan dipole as a 45 degree sloper (book show complete coverage
of all take off angles) or b) use a phased array of fan dipoles at 60/35/10'.
If b) will use a simple 3-port mini stack device from Array Solutions and keep
all 3 dipoles permanently stacked
3) If I do the 45 degree sloper, it seems the nulls are less of an
issue...according to the books. Would love to hear real life experience
4) If I do the stack of dipoles, I will configure them as inv-Vs to deal with
the nulls. Not an ideal solution, but better than flat dipoles.
Remember, when everything else fails and I need to work this rare W6/W7/XE
station I can always swing the beam. This contemplated setup is to avoid
wasting time waiting for the beam to turn from EU to US.
The tower is 90' AN Wireless with a 4 el 40m yagi at 90' and a 6 el tribander
at 105'. By next summer I will add a second tribander at 68' phased with the
top tribander. Between the stack of tribanders and whatever the simple US
antenna happens to be there should be good coverage of takeoff angles and
azimuth.
Rudy N2WQ
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