Topband: RX antennas and small vertical arrays

[n4is]

Larry

Thank you very much for sharing years of experience with us. I get involved
with RX antennas 5 years ago and I had relative success using a dual flag
array I named Waller Flag in a city lot.

I'm limited by a suburban lot with 150ft by 100 ft back yard, and the
solution that best worked for me was the dual flag end fire array.

After two years I started to test a new horizontal Waller Flag at 116 ft
high. I started it early spring. During the off season period the Horizontal
WF outperformed the Vertical WF by far, almost 85% of the time a weak signal
at noise level was only possible to copy using the HWF, may be because the
HWF reject most vertical noise from power lines. However during the last
weeks the HWF become useless.

Is it because of the summer Solstice?

You may be hit the nail in the head! When you said this;

>>.  I did this just before summer Solstice. 

>> The further away from Solstice, the better it worked. I concluded once
again that DX signals arrive at a very high angle far more often then
"conventional wisdom" would have one believe.

I worked 4 new countries on 160m during summer time that I was able to copy
only on the Horizontal WF, so I fully agree with you 100%.

One big difference between vertical, flag and beverages is the take off
angle.  The best forward gains for those antennas's are around these:

Dual Flag Vertical ............20 degree
Dual Flag Horizontal...........40 degree
Beverage  500ft................38 degree
4 sq vertical array............ 8 degree

If we think about different incident angle that is a clear difference
between those antennas even if the RDF are very similar around 11 db.

I have no real state to compare my WF's with beverage or a 4 sq array. So my
tests are only relatives with the plot I can capture and on air results.

After several years pushing the WF we have several well installed arrays
working quite well, and almost the same number of give up arrays that never
worked as expected. You named most of the common problems associated with
any RX array that for sure did contribute to some failure implementation.

The last simple update I did on my WF was the use of twisted pair from CAT 5
cable. It does not pick up any common mode noise and it is very simple for
any remote DX station to get it, just replacing all coax with the 100 ohms
twisted pair removed from Ethernet cable provides a low loss excellent feed
line and phase line as well, so balance lines were used in early 20's and
almost forgot in recent decades.

Another very important aspect of twisted pair is no need of choke to
eliminate the 3rd shield current, because there is no shield or 3rd current.
If choke or toroids are the limitation in a remote DX location to build RX
antenna, just use twisted pair on the RX antenna and go for it.

Back to small vertical arrays, I believe that twisted pair feed lines can
provide a better balance, and CAT5 of even CAT 3 is quite inexpensive as
well. This could be a nice solution for unbalanced currents. 

I'm planning to test a small passive 4 sq using this type of feed line next
season.

Regards
Carlos
N4IS