Hi all,
I do not believe that any " the best height above ground for Beverages RX
antenna" exists accurately. Just range of heights. All depends on local
situation of each QTH as far as earthy conductance, terrain profile, chances
of route and alternative exploitation methods of Beverages antennas
territory are concerned. The last mentioned is most important when over
whole year the Beverages RX antennas system is in use.
In my case fixed 6 long ( cca 400m + one 850m ) Beverages are in use over
whole year spread in star configuration which means that this system covers
50ha.and I must enable agriculturist to cultivate my property. So I had to
build Beverages antennas system at 4m of height to let them passage through
for tilling machines.
Nevertheless I am building another more Beverages during " winter " season
at the height of cca 1,5m. I found out that there is very very small
differences in reception between let say high and low Beverages if any at
all ( talking abt 160 and 80m ).
Another story is when comparing reception from Beverages and full sized
dipoles 4SQRs for 160 and 80 mtrs. In this case there are so substantial
differences in reception especially during each actual openings. The 4SQR
hears mostly better then Beverages and absolutely better during SR or SS but
when band is more noisy or long haul
DX is concerned then Beverage RX antenna is better longer time through one
opening.
This long term sighting of Top Band behaviour has validated me that the 8
circle verticals reception system by Tom ( W8JI ) has very very deep sense
because has narrow horizontal ray of reception but reasonable wide vertical
angle.
There is no other way then to build one soon and make further comparison.
73 Jarda OK1RD
PS: A friend of mine OK1MY, owner of cable factory has developed for me and
has started production of super strong and light conductor for Beverages
antennas especially.
The conductor contraction consist of highly conducting Cu rails and
fibreglass, has certificate for stretching of 150kp or 400kp and has UV
resistant insulating cover.
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