In a message dated 98-06-22 12:39:26 EDT, k6xx wrote:
<< If you use cross-polarization (one antenna vertical), your requirement
for separation is theoretically reduced.
Anyone ever try this at HF? I have--on 80m--but burned out a RX
attenuator. (Was happy to replace a resistor rather than something more
critical, though!) >>
YES! I did this at K2GL/N2AA back in the hey-day years of that operation. It
works REAL WELL....in at least ONE scenario. We ran our "big stack" of 10
over 10 up on the ridge. With it aimed at EUR, I walked the property and
found (by eye) the point where a vertical would be off the end of the elements
(perpendicular to the boom). I set up a pair of phased vertical for 10
meters. While the separation was "a bit more" then the 200'-300' mentioned in
the intiating question on this topic, I CAN say that it really works well. As
a BONUS, it is very good at knocking out USA qrm. I could get to within 5kc
of our xmiting frequency with ZERO filtering of any type and still have an S-1
noise floor. Of course, when the stack was somewhere else beside EUROPE, it
wasn't as good, though still useful.
I also CLEARLY recall a massive pileup on some guy in the Pacific (new mult)
and with ANY of the horizontal beams pointed at him (from the East Coast USA),
all I could hear was USA QRM calling him non-stop. When I switched to the
phased verticals (for RX), the USA signals DIED and the DX stuck out like a
sore thumb. I worked him on ONE CALL, while everybody else was still calling
due to their lack of ability to hear him! I enjoyed that one.
We also tried some sort of IF notch filter which worked too. I have NO IDEA
what it was as it was done independently by K2XR (in HZ for the last 15 or so
years). If you can find his address, ASK HIM.
Good Luck!
de Doug KR2Q
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