Since our new reflector has been "broken in" by its first thread ("Software
Questions"), I'd like to start another.
K9TM and I are putting together some gear and antennas to have a permanent
VHF setup here at K8CC. In the past, the constraints of underground
feedlines (or rather, the lack thereof) lead to temporary summer lashups
that had to be ripped down once the HF contest season arrived in the fall.
One of the main questions to be answered here concerns the preferred
heights for the 50 MHz antennas. I've looked at the 50 MHz setups from the
K8GP and W2SZ web sites, but their mountaintop locations offer advantages
my QTH doesn't have. I found some interesting 50 MHz configurations at the
W5KFT web site, but Texas and Michigan are somewhat dissimilar in terms of
the available target audience.
I think I understand HF wave angles, antenna heights and stacking pretty
well, but my feeling is that VHF is a different thing. 50 MHz might share
*some* characteristics of 28 MHz, so some of those techniques might apply
if the propagation modes are known.
My location is essentially flat terrain, and I have towers that go up to
120'. My thinking is that really tall heights are not necessarily needed,
since anything above 80' (four wavelengths) is essentially free
space. I've been told that a 30' antenna can be a real killer at times for
summer E-skip, so I was thinking about identical yagis at 60' and 30' with
upper/lower/both switching for wave angle control and the ability to spray
RF in different directions.
Thanks for any suggestions.
73,
Dave/K8CC
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