DIPOLES and LONG WIRES are EFFECTIVE DX Antennas
when installed at appropriate heights and in the clear.
Out of curiosity, I decided to see just what I could do with wire
antennas when the last of the WARC bands became available around
~1985. I've worked over 320 countries on EACH of WARC Bands
(30, 17, 12M), primarily using an 80M dipole running N/S at 70 ft,
another 80M dipole running NW / SE at 100 ft fed with 75 ohm coax,
a 20M dipole fed with Ladderline and also running N/S at 50 ft,
plus a 30M rotary dipole (gamma Matched boom of a TH6) at
80 ft.
The 80M dipoles act as current fed Long Wires (3/2 WL on 30M,
5/2 WL on 17M, and 7/2 WL on 12M) and can be fed with either
open wire line OR COAX with reasonable SWR (under 3:1 on 30M,
under 2:1 on 17 and 12M when tuned around 3.6 MHz).
Long Wire patterns have 4 major lobes, centered approximately
30 degrees each side of the wire, plus some smaller narrow lobes
in between. It takes several Long Wire Antennas to cover ALL directions.
The 20M ladderline fed dipole has a figure 8 pattern on 10, 12, 15, 17,
20, and 30M, varying in beamwidth from 50 degrees to 90 degrees
respectively. This antenna fills in the NULLS of the Long Wire
antennas.
One nice feature of using a 20M ladderline fed dipole on the High
Bands is that there are only 2 bidirectional lobes which are aimed
at the SAME heading on all 6 bands. Three such antennas oriented
at 60 degrees to each other would provide world wide coverage. A
pair oriented at 90 degrees to each other could cover most of the
important paths on all 6 bands.
Tom N4KG
On Tue, 17 Sep 2002 Chris BONDE <ve7hcb@rac.ca> writes:
> At 01:23 AM 2002-09-18 +0100, Tom Osborne wrote:
>
> >How true that is Pete. I worked 225 countries with an old TCM-2
> >Navy transmitter and a 135 foot center fed zepp. What does that
> >tell anyone? 73
> >Tom W7WHY
>
> To me it shows that you have a good QTH, the other operator also,
> and, operating during a good propagation period.
>
> Chris opr VE7HCB
>
>
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