Dear TopBanders,
many articles have already been written about receiving antennas for 160m,
the TopBand. As a matter of fact very few of them tell anything about
practical
comparison among them because most articles were concentrated on theoretical
discussion. Therefore I decided to write this submission for Topband Digest
panel. The article's objective is to tell those who are considering what
sort of reception antenna to select for the best reception on 160m. Of
course, every one has a different condition for building of RX antennas so
it would be reasonable to describe my conditions in which I have tested
antennas and gained my experience.
My QTH conditions:
1) area place: 50ha at my own disposal whole year
2) terrain topography: a hill top 600m a.s.l. with flat top area at cca 300m
in diameter, than slope down about 4% and further more around
3) quiet area for reception, no man/made noise
The following antennas were tested through whole year at least and compared
each other. All tests were done during last 5 years and when the result of
specific antenna were not satisfactory, antenna was replaced or left for
another year for further comparison:
a) 8 x single wire Beverage antennas in stars configuration each cca 400m
long at 3 to 4m up
b) 1x single wire Beverage antenna but over 850m long
c) the end fire Beverage array , 270m long at 5m distance, staggered 30m
d) broadside Beverages 400m long, 90m spacing
e) 4x two-wire switchable by directional Beverage antennas
f) dipole 4SQR ( designed for transmission ) phased 0 deg. - (-137deg.) -
(-263 deg.)
g) the Eight Circle array, 116m in diameter, 90deg. phasing
My subjective confrontation:
Based on my experience with long distance 160m communication I can offer the
following conclusions:
i) I prefer to 8 Circle to any other antenna except the cases when signals
arrive at high angles ( one is usable for one band only )
ii) broadside Beverages 400m long, 90m spacing but disadvantage is of course
necessity of enormous space to build it for all directions
iii) two-wire Beverages 400m long switchable by directional antenna which
are not extremely demanding of area compare to single wire Beverage antenna
in stars
configuration for all directions too. Overall performance - seems to me -
better than single wire ones
iv) single wire Beverage antennas in stars configuration: needs extremely
large area to build but good performer. Beverage's type of antennas ( single
and two wires ) have advantage of using them on more bands ( 160,80,40 mtrs
)
v) dipole 4SQR, an excellent transmission antenna on 160m band, can used for
reception usable too but it produces sometimes so strong signal tend
overload my IC756PRO2 receiver
vi) for reception on short distances or when signals arriving at high angles
( SS,SR conditions ) is better to use simple antennas like vertical or low
dipole
I did not mentioned loop antennas like: K9AY, EWE or shorten dipoles
rotatable Titanex which I tested them all during years. They are good for
limited area conditions but of course cannot be compared with above
antennas.
I do hope not to bore you Topbanders and I would be happy if my experience
with RX antennas for 160m band could help in thought about choosing good RX
antenna.
Wish you the best Dxing and good season on a Top band.
73 Jarda, OK1RD/ OK7XX from remote controlled QTH
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