Bill,
I suspect the 6dB increase in gain was due to the horizontal component
radiated when the antenna was bent over, not because it was grounded.
Being in Signal Corps and stationed in Berlin, I can tell you the main
reason we had our whips bent over was to keep them out of the high voltage
lines of the street cars!
What I taught the guys to do when they wanted more reliable communications
was to find a place to stop, about 30 ft. from a tree, remove the top two
sections of the whip, and screw in the whip-to-wire adapter, then string a
horizontal wire.
The inverted-L significantly outperformed the whip.
Actually the inverted ought to be the antenna of choice for many people,
because it has a vertical component for DX and a horizontal component for
NVIS.
Most people have forgotten (or never knew) how well this antenna can
perform.
73
Rick
-----Original Message-----
From: tentec-bounces@contesting.com [mailto:tentec-bounces@contesting.com]
On Behalf Of Bill Harris
Sent: Friday, December 31, 2010 4:34 PM
To: tentec@contesting.com; ken.d.brown@hawaiiantel.net
Cc: geraldj@weather.net
Subject: Re: [TenTec] New and Improved Terminology/Gnded tip on whip ant.
FYI
wb2vuf's comments remind me of an article in CQ, early fifties (I believe)
The author pulled his 75 meter whip antenna over and grounded the tip on the
front bumper. The picture of the car was on the front cover; A Studebaker
convertible. If my memory serves me right, the author said it increased his
signal approximately 6 db.
This article was before the Korean Police Action. During the"PA", the Army
did utilize pulled over whip antennas on their communication trucks; A
deuce and a half with an HU17 com/hut on back, pulling a trailed AC
generator. Mobile rig was a BC-610 xmtr. & a BC312(?) Worked great for
short skip.
There may be a few of you who still have a copy of that CQ issue. I'm still
looking for mine.
Happy New Year ya all.
BillHarris/w7kxb
> Date: Fri, 31 Dec 2010 15:28:18 -0500
> From: wb2vuf@verizon.net
> Subject: Re: [TenTec] New and Improved Terminology
>
> 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.
>
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