R: [TowerTalk] 160M Wire Antenna

[i4jmy@iol.it]

The assumption a relatively low (90 Ft) horizontal antenna can be a 
decent one for 160m, also DX, is true when referred to people who have 
not the room for large vertical/s (arrays) neither the space required 
for a set of separate receiving antennas or when comparing the "wire" 
to the efficiency of short loaded verticals (expecially when roof 
mounted) that's generally minimal at any of the radition angles.
A symple quarter wave vertical radiator is definitely able to outperform
a single element horizontal dipole system at 1/4 wavelenght from ground 
and often also at 1/2 wavelenght.
The above is real when the very low angles of the vertical antenna are 
present (a very good ground plane is required) and useable, the used 
power is enough to compensate the wave attenuation caused by the long 
travel through the D layer in the ionosphere, and expecially if a set 
of 6x2 wavelenght (or something equivalent) long beverages are used to
upgrade receiving to the transmitting capability.
It's same evident that a quarter wave GP on 160m, or any derived 
antenna, requires a very tall structure, a large and efficient ground 
plane, and suffers if tall buildings are sorrounding it. (not counting 
for TVI and BCI problems if someone, expecially when not Ham oriented, 
lives inside those buildings)
Without separate antennas for receiving (or other phased verticals to 
obtain a pattern) a GP is mostly a transmitting DX machine while under 
the receiving point, expecially SSB were a bigger S/N is required and 
the receiver filter can't be so narrow like on CW, is a fair/poor tool 
unable to satisfy DX requirements.
Althoug beeing a contester myself, a "state of the art" 160m antenna 
farm can't usefully apply when the actual problem is what to use as a 
160m antenna in a typically constrained situation.

73,
Mauri I4JMY





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