Merry Christmas!!
I asked:
"Can anyone give me a comparison between their 4 square arrays or parasitic
arrays and a beverage for receive? In his latest book John alludes to
directive antennas (yagis and arrays) negating the need for beverages. I
was curious about your experiences.
Please describe your array, and your beverage system (heigth, length,
favored direction)"
---------------------------------
Quick overview: The East Coasters seem to like what ever they already
have, seems like they can work Europe with a sling shot. As you move
inland results vary. I get the jist that an array and a 500ft beverage are
about on par with one another, with each favoring a different angle of
radiation and time of night.(read the submitions, they are informative).
If you can manage a 1000 to 1200ft beverage, I wouldn't recommend rolling
it up just yet.
Here we go!
I find that my top-loaded four-square array has pretty much negated the
need for
beverages on receive. This is certainly the case during the winter and any
other
time that conditions are relatively quite. The only time I find I need a
beverage is during the late spring and summer when the static becomes intense.
Of course, there isn't that much DX to be had during these times anyway. Of
course, I'm in western Massachusetts with not too much land mass between my
location and the ocean, so beaming northeast I may have quieter conditions
than
someone in the midwest beaming northeast with the same antenna.
Hope this helps...
Rolfe, W1VC
---------------------------------
I have a 4-square for 160 and for 80. I also have Beverages. Towards
Europe I have two 1100' Beverages, otherwise they are about 550' long..
The 4-square is only better at sunset or sunrise, otherwise the Beverages
are equal to or better than the 4-squares. If nothing else, having two
choices is a good thing!
-- Tom K1KI
----------------------------------
Jay, I have 2 500 ft. Beverages and a EWE for receive.
Since I put up my 2 element inverted L array last season I find the RX
antennas offer less improvement on receive! SOmetimes the array is even
better.
The array is right out of ON4UN's book; 2 1/4 wave inverted Ls spaced
1/8 wave apart. I have 4 elevated radials on 1 and 8 on the other.
My vertical heights are 60 ft. with the horizontals about 70 feet.
The radials are from 6 to 24 feet above the ground.
73,
Sid K3SX
------------------------------------
80m 4x elevated array, Comtek Box, full sized wire elements.
my beverage is heigth: 4-10'
length: 200-300'
favored direction: 60 degrees
I took down the Beverage(s) as the 4x array
hears better. I've had others state the same.
However, for certain noise problems a proper
Beverage might still have the edge ... When I
used the short (200-300') Beverages on 160m,
the single 160m vertical was as good or better
most of the time. I really need more space
between the low band xmit antennas and the
rcve antennas, that I believe is really
limiting the performance of the short Beverages.
They were too close to the xmit antennas
and needed to be longer ....
73 Billy AA4NU
--------------------------
> Please describe your array
4 element parasitic vertical array. Three elements are in-line and
active towards Europe (or switched to South Pacific). The other
element can be used towards either to eastern Asia or South America.
The driven element is a tower structure 105' tall, shunt fed. The
EU parasitics are 88' tall, near top loaded--the top 20' is fiber-
glass tubing on which a loading coil is wound (mostly at its bottom).
> (Please describe your) Beverage system
Degrees Length Height
8 584 9 to 3'
30 885 3'
43 380 10' Zero ohm termination
86 544 3'
140 584 3'
261 584 3'
323 883 3'
352 584 3'
> (Not asked, but important) What is your ground conductivity
Excellent: 40ms
Since my schedule and antennas favor Europe/western Asia, my comments
will be in response to comparisons to that area. The TYPICAL
difference this year has been that a Beverage (most commonly the 30
degree one) produces a 2 dB better signal-to-noise ratio. Differences
have ranged from the transmit antenna being 5 dB better to a Beverage
being 10 dB better. A rule that I haven't seen broken at this location
is: If the sun is shining, the Beverage will be the better antenna
for receive--the more sun, the greater the difference...
Given the difference between the my transmit antenna and the
Beverages--the Beverages have to be done right or it's not worth the
trouble. Obviously, a few dB decrease in performance will make them
of no value.
I'm curious as to the other responses, Jay.
73, Bill K0HA
-------------------------------------
I don't have a 4-square, but here's my report comparing Beverages to my
2-el phased array (shunt-fed towers spaced 1/4-wave on 160m).
I once had 4 Beverages in various directions (NE, E, NW and SW), before
the local population explosion in the 80s forced me to take them down.
Three of them were 550' long, and the SW one was 1100' long. In my xmit
array's endfire directions (where the pattern is unidirectional - NE and
SW), the 550-footers were about the same as the tower on receive. In the
array's broadside direction (bi-directional to the NW/SE, actually an
almost circular pattern), a 550' Beverage was superior (NW, to JA). The
1100-footer was always superior on receive for VK/ZL compared to my SW
unidirectional array.
The Beverages were 7' high, with the last 50' or so of both ends sloping
to the ground. They were constructed of galvanized steel electric fence
wire, which I found to be superior to copper wire for a Beverage (because
of greater wire loss, any signal refelected from the far end of the
Beverage was attenuated more than it would be in copper, so the Beverage
had better F/B, therefore lower noise and better S/N).
The termination resistance for my Beverages (erected above "very poor"
desert soil) was about 300 ohms, determined by applying about 1 watt of
RF to the wire and walking down the wire with a FS meter and adjusting
the resistance for flattest standing wave on the wire (the method
recommended by H.H. Beverage himself).
I would suspect that a well-tuned (emphasize "well-tuned") 4-square array
would obviate the need for a Beverage, but one never knows.
Anxious to hear your summary of replies.
73, de Earl, K6SE
----------------------------
I have used an 80 meter 4 square array for 3 years. I still use my
beverages. I have 5 terminated beverages in varying directions.
Sometimes you can simply use the 4 square, but not all the time. Always
better to have LOTS of antennas! Steve, NN4T.
----------------------------------
I recall the same statement in the book, and I think it is a bit of an
oversimplification.
The 4-square may be better on receive than a short Beverage, i.e. less than
1 wavelength long. However, I doubt that's true for longer Beverages (say
2wavelengths or more) simply because the Beverage produces a much
narrowerforward lobe and has MUCH better F/S and at least as good F/B as
the 4-square.In other words, the Beverage provides better rejection of
signals and noise not in the main lobe. My Beverages show up to 30 dB F/S.
The 4-square is not even close here. The only possible advantage for the
4-square (and I would have to check the radiation patterns to verify this)
would be in reception of particular wave
angles in the vertical plane where the Beverage might have "holes". The
other exception might be over extremely good ground, like salt water, where
a Beverage may not work well (Beverages actually prefer poorer ground) and
where verticals really do perform exceptionally well at low angles.
I don't use a directional transmit array on 160, but I do run a "homebrew"
3 element triangular phased vertical array on 80. My 500 foot Beverages
are ALWAYS better on receive in their aimed directions than the verticals
and it's not a case of underperforming verticals. The verticals are proven
performers--check the DX contest results on 80 m going back to the mid-1980's.
73, John W1FV
---------------------------------
Regarding your question if Beverages are not needed if you have a
4-Square, I can tell you that this is NOT true, no matter who wrote
it in a book. Having operated the 160 Meter position at W3LPL for the past
three years during the CQWW & ARRL DX Contests, I've had the opportunity
to try all combinations of receive antennas. Frank has numerous Beverage
antennas, some single, some phased in the W3LPL array of antennas. Although
there are times when the 4-Square will outperform the Beverages, there are
even more times where the Beverage will hear better than the 4-Square.
This has been noted in noisey as well as relatively quiet conditions.
In addition to the 4-Square, other Top Band antennas include verticals
which favor NE, S, W & NW and the NE, E, S, W & NW Beverages. As Frank
reminds us, a Ham never has enough antennas. With this in mind, I believe
that we be seeing a few more 160 Meter antennas in the next year or so,
hopefully a pair of low dipoles at W3LPL for those times when the high
angle signals predominate.
Bottom line....you never have enough of them.
73 de Rich - K1HTV
-------------------------------------
Continued
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