Topband: NEW RX HWF antenna report Spring to Fall (n4is)

NX4D NX4D at comcast.net
Mon Dec 28 13:23:15 PST 2009


Gentlemen:

One-Sixty, not being a plug-and-play band, often tends to drive one to 
extremes, or at least to higher levels of creativity, than on the HF bands.

N4IS, JCarlos, called me some time back and asked me to listen to a 
frequency on 75SSB.  My vertically polarized loops beaming EU, only heard 
frying noise that early in the afternoon.  Carlos turned his rx gain up so I 
could witness similar reception on his vertical loops.

Then he said:  "Now, listen to this".  I then heard the most astounding 
75SSB reception wide open to EU.  There was no noise, only clear armchair 
copy of stations in QSO.  Carlos lives in a suburban area just north of rf 
noisy Miami.  He had mounted dual phased loops at about 100 ft. high, 
deploying them horizontal.  Obviously this horizontal setup was insensitive 
to the ambient manmade noises of that area.  The directional pattern of the 
loops added additional performance.

During this time Carlos has endured several loud power pole buzzes which 
just destroyed his vertical loops reception.  The horizontal loops have 
allowed him to continue working new countries on 80 and 160m.  The modeled 
max gain angle is about 42 elevation degrees for 160m, but the loops hear 
well at lower angles.  I believe this directional rx antenna works better 
than a 160m dipole at any reasonable height for other than possibly some 
sunrise receptions with sigs arriving perpendicularly "straight up".

Next, someone needs to devise a method to differentiate between the direct 
horizontal signal and the out-of-phase, ground-reflected one, so the ground 
reflected signal can be eliminated.  A horizontally polarized low band rx 
antenna may then be possible having a reception lobe of 20 elevation degrees 
and 12dB+ RDF.  Such an antenna mounted rotatably near the ground could 
possibly open the topband up in noisy countries around the world.  The U.S. 
little gun could have some low band fun too.

With seemingly unlimited ideas and enthusiasm, JCarlos could be the man to 
find the next breakthrough.

My two cents worth for 2009.  Happy 2010 to all.

73/DX, om Doug / Nx4d 



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