> The diversity combining info was interesting. I have an
R5 vertical
> mounted a foot or so above my old TH3 tri-bander. The TH3
will often
> hear signals Q4-5 which are inaudible on the R5. I have
never bothered
> to look, but, under these conditions, the S meter should
show noise from
> the vertical to be substantially more than that from the
beam.
I'm a big fan of diversity receiving systems.
I use stereo. I use spatial diversity on 160 and 80 meters
because I only have vertically polarized antennas with good
directivity on those bands.
http://www.w8ji.com/receiving.htm
On 40M I can use either spatial or polarization diversity.
My antennas are here:
http://www.w8ji.com/my_shack.htm
I don't know what 20 and higher are. I don't work them much,
but when I do signals are like on a telephone.
On 160 meters, I need about 2000 feet spacing to get good
diversity. On bands where I can do both polarization and
spatial diversity, like 40, I find spatial works better than
polarization diversity.
The largest effect I hear isn't a reduction of QSB. It is
the fact noise takes a hollow sound and signals are easier
to pull out when near noise floor. Signals that are only
occasional letters and beeps on either channel become
perfectly readable in stereo.
I've found this requires the receivers for each channel be
PERFECTLY phase locked and have nearly identical
characteristics for maximum effect.
http://www.w8ji.com/polarization_and_diversity.htm
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