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Old January 9th 08, 09:03 PM posted to rec.radio.shortwave
bpnjensen bpnjensen is offline
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First recorded activity by RadioBanter: Jul 2006
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Default Which Noise Cancelling Antenna Would You Choose ?

On Jan 9, 9:36*am, RHF wrote:

BpnJ - Do you have either -or- Used Either ? ~ RHF


As I mentioned in earlier post (did you not receive it?) I have the
1026, and it works pretty well. Here is the text:

My MFJ-1026 works very well for some kinds of noise, with two rather

dissimilar external antennas attached. It gets rid of most of the
noise that I hoped it would, that is, the continuous static and
droning kinds of things (only one noise source at a time, however).
It could probably get rid of lightining crashes and sporadic noise as
well, but in practice the knob-twiddling required takes a tiny bit
too
long for it to be effective; ANL and NB work better for those
sources.

There is some minor internal diddling that must be done, explained in
the manual, depending on your antenna configuration, but it is very
easy and quickly accomplished. Some people install a switch to
reverse the main and accessory antennas, and it is too bad that MFJ
have not simply provided one. I will probably do this on mine
eventually. There are plans for this on the web, IIRC, another very
simple mod.

This unit also attenuates MW, especially at the low end; there is a
specific component inside that can simply be crushed to eliminate
this
attenuation if MW is high on your list of uses for this device. In
fact, some like it just for that reason, because it is VERY effective
at nulling strong stations so that weak ones can be heard underneath.
I have tried this on several occasions, and have been astonished at
how well it works.

I would get one again (maybe even two in tandem if two sources of
noise are annoying simultaneously), but I think for best results you
need two antennas that are very close in design. You should have
plenty of room up thar in the hills for that!

I would add to the initial post that, the reason I think two similar
antennas would be better is because you really want each of them to
"hear" the same noise at roughly the same level and the same way. The
ability to null that noise is optimized when the noise signals are
about the same strength. Having said this, it is best also to have
the antennas separated by a fraction of wavelength of interest, which
is usually not a problem for most people.

Right now, I am using a DXUltra sloped multiband Dipole and a 45'
random wire; these two are fairly effective together, but I think that
two dipoles or two similar random wires would be even better - based
on my limited experience, I think I could get some really deep, quiet
nulls on pretty nasty noise with that setup. I just wish I only had
one noise source!

BJ