Hi,
Last weekend I finally got into experimenting with phased beverages, something
I was planning for some time.
I installed 3 broadside 219m (718ft) long beverages into the forest looking at
90 degrees and separated 60m (200ft) from each other (120m between the outer
ones).
I took great care to make sure the wires are straight and fully parallel to
each other as well as starting from the the same line.
I use DXE 9:1 beverage transformers and DXE 470 ohm termination resistors.
I brought 150m (500ft) 50 ohm cable from each beverage feedpoint to the shack
and connected to Microham Stack Switch (like Stackmatch). All the cables were
of identical length to ensure same phasing.
So I presume this system gives me full ability to test any combination of those
3 beverages alone or phased with each other?
Well, all the 3 beverages alone are quite identical indeed which is good.
But now when switched in pairs or all 3 together I am not seeing much effect. I
do know what the patterns should look like and I presumed the effect would be
strong especially with signals coming from side but most of the time I notice
no difference with any signals when comparing any single beverages to
combinations.
This is puzzling. Modelling suggests I should for example have very big
improvements in suppressing signals 45 degrees off on 160m when using 2 phased
beverages 120m apart as well as when using all 3 beverages on 80m but I did not
notice such drops of 10-20db almost in any signals from any off directions.
I could hardly notice sometimes the expected 3-5db increase in the signals from
the right direction but not always as well.
Can some of you having experiences with phased beverages tell me if I have done
something wrong in my setup?? Should I test them differently? Are the phased
beverages overrated and in real life there is seldom a significant improvement
over 1 single wire beverage that is already long enough like 220m in my case?
Look forward to any input. I can send the modelled patterns and maps of my
beverages in picture files to anyone interested.
73
Tonno
ES5TV
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