[SECC] New Beverage at W8FN

[Randy Farmer]

I barely managed to get my new Unified Microsystems (W9XT) BevFlex-4X 
Beverage installed and operating for the CQ CW contest last weekend. I 
installed it Friday but encountered problems with one of the feedlines; 
that problem wasn't corrected until Saturday morning. It appeared to be 
a bad arc capsule in the lightning protector for that antenna. I 
replaced the capsule and all was well. It took a lot longer to find than 
it did to fix, of course. The antenna isn't really fully installed yet, 
just "roughed in". I still need to go back in the woods and secure the 
terminator and feed boxes to their supporting trees and waterproof all 
the connectors.

I chose the BevFlex antenna because it allows for bidirectional 
patterns, and the feedpoint can be located anywhere along the antenna. 
It's constructed using RG-6 coax, and all connections to termination 
boxes and the feedpoint box are F connectors. The design requires 
separate feedlines for the Forward and Reverse feeds. I used a 100' 
length of "siamese" dual RG-6 Quad shielded coax to run the feeds to the 
station. It's necessary to terminate the unused direction's feedline 
with a 75Ω load to make the reflection transformers work properly. A 
small switch box that does this is included as part of the kit. Since 
all my switching is remotely controlled, I built a new relay box to 
handle the reversal function under software control. My property can 
support a length of about 350 feet in the NE-SW direction I ran the 
antenna, so that's the length I used. I just mounted the coax by running 
it through  a series of screw-in insulators installed about head high in 
the trees. The feedpoint is located about 240' from the NE end.

Initial checks with AM broadcast band stations looked encouraging. Even 
with daytime propagation, there was obviously a real signal strength 
change when the two directions were selected. The rather short 350' 
length made the antenna pretty much omnidirectional below 1200 kHz, but 
at 1400 kHz and higher  there was a noticeable change in signal strength 
on many BC stations when the direction was changed. In a couple of 
cases, one station was actually replaced with another.

Returning to the contest, I first tried the Beverage on 20 meters. By 
the time I got back on the air, around 2000Z, 20 meter propagation to 
Europe was essentially gone for me. I wasn't hearing many signals other 
than strong US and VE stations. It wasn't clear whether or not the 
Beverage would be useful on 20. When I changed to 40 meters it became 
obvious that the Beverage was going to be very useful. I was immediately 
hearing  lots of weak EU signals on the Beverage that were difficult or 
impossible to hear on the inverted vee transmit antenna. Using a 
combination of the transmit antenna and the Beverage in Diversity mode 
made copy of weak DX stations dramatically better. I was literally 
hearing a whole new layer of DX signals that were extremely marginal 
copy on just the transmit antenna alone. Sometimes when QSB would take 
the signal out on one antenna and it would be Q5 copy on the other. Most 
of the time I used the Beverage in the NE direction since most of the DX 
was from Europe. Switching the Beverage to the SW direction would 
usually make the EU signals completely disappear. Unfortunately, this 
vastly improved receive capability proved to be  a double-edged sword. I 
found I was clearly hearing a bunch of DX that couldn't hear my 500W to 
an inverted vee at all. Repeated calls to many Q5 EU stations went 
unheard on their end.

Around sunset, I went to 80 meters and had similar results. The 
superiority of the Beverage to the inverted vee transmit antenna was 
even more dramatic. In Diversity mode, many times  I could easily copy 
EU stations on the Beverage that I couldn't hear at all on the transmit 
antenna. In some cases, I could hear them working other EU stations and 
both sides of the QSO were inaudible on the transmit antenna. Of course, 
the disparity between receive and transmit capability was even more 
apparent on 80 than on 40. It quickly became evident that if I want to 
work DX on 80 I'll need to come up with a significantly better transmit 
antenna.
I have no 160 meter antenna so far, so I just spent a few minutes 
listening on 160 meters. I was able to hear some EU stations on the 
Beverage quite well. Unfortunately, I also found that there was some 
kind of ugly local electrical noise on 160 that I'll need to track down 
and get fixed before I can expect to do anything on that band.

After the contest, I've been listening around on the bands to get a 
better idea of what the Beverage can do. I've found that it does work 
pretty well on 20 meters and definitely improves copy on marginal 
signals in Diversity receive mode. It's also extremely effective on 40 
meters, especially at night. In the Wednesday morning CWT session it 
didn't really seem to do much on 40, but signals for the most part were 
short skip and quite strong. On 80 meters I found that it is definitely 
useful on stateside signals. In the Wednesday CWT it helped a lot in 
improving copy on many domestic signals, even in the morning. I also 
hooked just the Beverage up to my Airspy HF+ Discovery SDR and tuned up 
and down the AM broadcast band. Above about 1300 kHz the Beverage starts 
to develop very good directivity and on many frequencies switching 
directions would replace one station with another. This effect was 
especially noticeable at night.

In summary, This Thing Works! I'm very happy with the station receive 
capability improvement it gives. As a matter of facti, I'm now looking 
at installing a second BevFlex-4X in a SE/NW orientation. It's somewhat 
uncommon for an antenna project that involves a modest amount of effort 
and expense to make a dramatic difference in station performance. This 
one did.

73...
Randy, W8FN
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