at picture for a larger view.
L-shaped 120 meters
By Jose M. Valdes R., YV5LIX
Special for hcdx, 5 June 2002
This antenna is in fact a "sloping long wire" that I
use for SWL with excellent results in the MW and SW bands. Signals
are quieter and better than on a dipole cut to the frequency in
Because this antenna uses a tower, as part of the support and
radiation system, it is not an antenna for everyone, but never
the less it may give you some interesting ideas to work on.
The antenna is a 120 meters long wire layout on a "L"
shape to fit in a medium size city lot (see illustration).
It slopes down from a 15 meters tower (that support my amateur
radio antennas, and acts as a capacitance hat), to a 9 meters
high mast located 40 meters away from the tower. and from there
diagonally to the back of my lot for another 80 meters.
To make the tower some what electrically longer and to provide
a more omnidirectional pattern, six random length radial are attached
to the bottom of the tower, the end insulator at the end of the
antenna is at 3 meters above ground, and for better performance
I use an antenna.
One interesting feature of this antenna is that it is very
good for MW DX. Some of the loggings made at my QTH in Caracas,
Venezuela, can be heard here, :
1460 kHz -- Nuevo
Continente, HJJW, in Bogotá, Colombia. [92 K
18940 kHz -- believed to be Radio
Afghanistan [251 K realaudio file], heard on May 31
2002 at 1400 UTC, the first day that this new signal was heard
with a regular program instead of the test fanfare that was heard
the previous days.
These recordings may give you an idea of the very good performance
of the "sloping long wire".
As you may know, Caracas is not the best location for MW DX due
to the great amount of local MW stations.
But with a good antenna, interesting logs can still be made.