Hello All,
As an ex-Navy MARS and current Army MARS operator, when assisting new members I have always found that
a low to the ground mounted random wire, inverted V
or dipole to work well depending on your surroundings.
However, what works BEST from my experience for the
4-30Mhz range is a 135 foot wire span dipole drooped
between a dipole/inverted V with the center at about 20-25 feet above ground level using 450 ohm ladder line to a 9:1 balun to coax into the building.
My current installations at both my residence and my clubs MARS station using this design, I make use of
a 9:1 W2FMI model 9:1-HB450 ferrite core balun transformer and 12 gauge steel core copper 450 ohm
ladder line wire with a heavy duty center insulator/support and reinforced connections to handle the New Jersey winters. A ground connection from the balun body along with the polyphaser lightening arrestor is taken to an 8 foot copper clad ground rod 9 feet below the balun at the rear of the building.
At my residence, where the entire antenna and feed line
is in the clear, the antenna never goes abovea 2.5:1 VSWR from 3-30Mhz and has multiple points, many within our Amateur bands where the VSWR is less than 1.8:1,
at the club station, where the antenna is near a standard bob wire military fence, the VSWR is similiar in that it is never over 3.1:1, however it never goes
below 2.1:1 except at 20 meters where it is 1.7:1
The performance of the antenna is superior to any thing available for comparison, to include resonant
dipoles, inverted V, G5RV and Carolina Windom antennae.
Sincerely,
/s/ Steve Hajducek, N2CKH/AAR2EY (ex-NNN0WWL)