We called it "short skip", during my misspent youth. From my Novice
days in 1966 to the present, I don't think I've ever had an antenna
higher than about 25 feet anyway. I work mostly 80 m traffic nets,
where we're more interested in covering the state than in DX. Years
ago, I put up a ground mounted trap vertical because there were no big
trees at the QTH. On 75m I couldn't be heard 5 miles away. I then
rigged a low 1/4 wave inverted "L" fed at the base of the vertical and
got instant statewide coverage.
Today, when I go on vacation with my Ten-Tec Scout, I rig a low 80 meter
dipole. Operating from a wooded lake valley, I get great signal reports
on 80, with signal strength at a range of 50 miles as good a my signal
at 5 miles.
I first heard the term NVIS (Near Vertical Incident Skywave) back in
1981. I was doing flight testing some navigation equipment at Lakehurst
Naval Air Station on NJ and I came a cross a couple of guys with a Huey
helicopter and an old Dodge M37 truck with some funny antennas on them.
They called the antennas shorted loops. They were sort of half loops
with the far end grounded to the helicopter tail boom or to the truck's
front brush guard. They were simultaneously developing these low-profile
antennas and experimenting with HF NVIS. The need for this in a
helicopter came out of the Viet Nam experience where it was proven that
a high flying helicopter is pretty vulnerable to ground fire. The new
aviation doctrine that evolved from that is "nap of the earth" (NOE)
flying where the helo flies low and scoots through valleys and ducks
behind hills. This kind of flying is not conducive to VHF line of sight
communication, hence the need for HF NVIS operation. HF NVIS was also
used during Operation Desert Storm, particularly since there were not
enough SATCOM channels to go around.
Anyway, it works for me and my operating style. I use a low 80 meter
dipole plus a low 65 foot inverted L as a backup. The big rigs (Paragon
and Corsair) do fine, but the system works well for the little rigs
(Scout and Century 22) which only run 20 or 30 watts.
73,
Bob WB2VUF
On 12/30/2010 10:25 PM, Ken Brown wrote:
>> We used low antennas out of necessity long before the military called
>> them NVIS and on 80 and 40 worked the surrounding states very well for
>> ragchews, nets, and FD.
>>
> When I was a Novice, my mentors called it "short haul skip." One of
> those was a former Air Force radio man, and if NVIS had been a common
> term used by the Air Force, I probably would have heard it from him. I
> did not hear that term until perhaps the 80s. Maybe it did come from the
> military. I'm curious about it's origin. Maybe the Army or Navy used it,
> but I'm pretty sure the Air Force did not use that term back in the 60s
> or 70s.
>
> DE N6KB
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