On 8 Sep 2005 08:17:00 -0700, "bpnjensen" wrote:

I agree in general, except for the fact that a dipole has a
characteristic directionality, whereas a random wire significantly
shorter than the wavelength will be omnidirectional. I suspect that
there will be occasional times when this factor matters.

When it doesn't matter, a random wire is still a more versatile antenna
than a single-lambda dipole, even when untuned.

I have an Alpha-Delta DXUltra, which is basically a multi-lambda
dipole, and a 60-foot random wire through a transformer at 20 feet
elevation above ground. Noise levels aside, there is little I can hear
on the DXUltra that doesn't appear on the wire, and quite a bit on the
wire, especially at freqs 6 MHz, that is inaudible on the DXUltra
(even though the DXUltra supposedly is good down to 120 meters - this
loss of signal may be a function of inadequate height, since the
antenna center is only 27 feet sloping to 7 feet at either end).

Bruce Jensen

I find a random wire superior overall to just about any ''tailor
made'' SWL antenna I've tried.

I find a random wire superior overall to just about any ''tailor
made'' SWL antenna I've tried.

I do find that the dipole is wonderful on 7 MHz, and 11 MHz and up. On
9 and 6 it's about a toss-up, and on down through the tropicals the
wire is better.

My big problem is noise, especially on the lower bands. I have an MFJ
noise cancelling unit that works with the two antennas, but I think two
simpel wires phased would work rather better. If I can arrange such an
array that can be set up on my smallish property, I will let folks
know. Meanwhile, I still have a large horizontal loop to build around
my fence...

Bruce Jensen

On 8 Sep 2005 10:34:24 -0700, "bpnjensen" wrote:

I find a random wire superior overall to just about any ''tailor
made'' SWL antenna I've tried.

I do find that the dipole is wonderful on 7 MHz, and 11 MHz and up. On
9 and 6 it's about a toss-up, and on down through the tropicals the
wire is better.

My big problem is noise, especially on the lower bands. I have an MFJ
noise cancelling unit that works with the two antennas, but I think two
simpel wires phased would work rather better. If I can arrange such an
array that can be set up on my smallish property, I will let folks
know. Meanwhile, I still have a large horizontal loop to build around
my fence...

Bruce Jensen

I've used the MFJ Noise Canceller with an MFJ-1024 Remote Active
antenna for the noise sense with decent results. Since then I ditched
my Linksys router and 90% of the noise went away.

In article ,
David wrote:

On 8 Sep 2005 08:17:00 -0700, "bpnjensen" wrote:

I agree in general, except for the fact that a dipole has a
characteristic directionality, whereas a random wire significantly
shorter than the wavelength will be omnidirectional. I suspect that
there will be occasional times when this factor matters.

When it doesn't matter, a random wire is still a more versatile antenna
than a single-lambda dipole, even when untuned.

I have an Alpha-Delta DXUltra, which is basically a multi-lambda
dipole, and a 60-foot random wire through a transformer at 20 feet
elevation above ground. Noise levels aside, there is little I can hear
on the DXUltra that doesn't appear on the wire, and quite a bit on the
wire, especially at freqs 6 MHz, that is inaudible on the DXUltra
(even though the DXUltra supposedly is good down to 120 meters - this
loss of signal may be a function of inadequate height, since the
antenna center is only 27 feet sloping to 7 feet at either end).

Bruce Jensen

I find a random wire superior overall to just about any ''tailor
made'' SWL antenna I've tried.

An antenna "tailored" for a frequency will pick up more signal energy on
that frequency than an antenna of the same type that is not resonant at
that frequency.

--
Telamon
Ventura, California

Telamon - I 'theory' you are correct.