10m ground wave expectations
The local station here is at 1500 ft + 35ft hi gain vertical at 50W,
with a 2200ft ridge less than 5 miles away... back down to probably
1500 ft until... About 60 miles from here is the tallish 3500ish ft.
mountains and then its down basically to sea level for the remainder.
This does seem to produce a rather sharp angle at the both ends. So
much so that I have trouble hitting the 3500ft repeaters from here
without going up to the big antenna. I do remember hitting some
repeater off to the side of the direct path about 10 years ago with
just a handheld and some gainy portable antenna (don't even remember
which one)... but haven't been able to find it since! Doh!
I'll probably end up just finding some 2m stuff to work. We have a
few linked 440 systems (California) too...
Joey
On Fri, 27 Apr 2007 20:40:51 -0500, Tom Ring
wrote:
Joey wrote:
Hi,
I'm trying to determine if I could use 10 meters to contact a station
about 75 miles away with about 2500ft elevation of a couple sets of
hills in between with just simple antennas on either end. Perhaps a
10m dipole on one end and some kind of stealthy one on the other. I
assume this would have to be ground wave only given the distance and
current band conditions.
My parents are both techs so we're currrently limited to parts of 10m
as the lowest band and I'd like to have something reliable without
need repeaters for disaster comms. We actually only have a few single
hop VHF/UHF repeaters between us, though quite a few linked ones.
I've also thought of 6m due to smaller antenna requirements, but I'm
pretty sure this is too far...
Thanks!
2m SSB or CW with modest power and antennas have a great chance of doing
what you wish.
A better description of the terrain would help.
2500 above mean average terrain? (I doubt that but have to ask)
A couple of hills. Sharp ridges? Above the line of sight?
Probably still quite doable. I used to work from Potsdam NY to
Plattsburgh NY (and a good chunk of Vermont) virtually every evening on
144.200 with a 12 foot yagi at 25 feet on my end, a 17 foot on the
other, using about 60 watts, and the Tug Hill Plateau and a couple small
mountains in the way.
2m "weak signal" is an often overlooked mode for 60 to 150 miles that is
very reliable for point to point.
tom
K0TAR
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