Topband: 2 Parallel Beverages close together, do they work?
Neil G0JHC
g0jhc at blueyonder.co.uk
Wed May 23 04:28:21 PDT 2012
I have recently installed 2 parallel Beverages on the same supports and at
times these follow just above a barbed wire fence.
I have experimented with various reflection transformers and 2-ways but
have always been disappointed with the reverse direction. I think the 2
way using reflection transforms requires some experimenting and precise
setup before they work. I would not regard them as a plug & play
installation, but thats not to say they dont work if you can follow all
the rules.
I have also considered various 2 ways using a single wire, but prefer to
keep it simple and not have relays fail or volts disappear over long runs,
followed by fault finding in the sub zero dark after work.
Here is a bit more detail.
They are both just short of 1000ft.
One points west and the other east.
Both are made from WD1A wire with both conductors soldered together at each
end.
One is fed with around 150m of flooded type low loss coax ( under 1dB
loss on 160) and the other is fed with 400m (measured at around 2.8dB
loss).
The coax to the top end Beverage is laid on the ground right under both
Bevs.
The separation distance is around 2 ft.
At each end I did stagger finishing and starting by around 30ft , both Bevs
have their own earth rods with a 4 set of 33ft radials. I terminate with a
390 ohm which brings me up to around 450 in total.
So as the purest would tell you, I broke quite a few of the rules.
So the question is do they work ?
I am stunned at the results, pattern is excellent and F/B superb. Most of my
testing to date has been on 80m, as they have only been up a month and 160
has been poor. Pattern fits in well with a 3dB beam width of around 80
degrees on 160. F/B is quite stunning 4-5 S points at times (all dependant
on arrival angle of course).
One of my best tests to date is on two local radio stations on the same Freq
of 1.540MHz, one 100 miles east the other 100 miles west, both are 55 and
mixing badly on my N/S (off the side of course)
switch to the east and all
I have is the east station at 59, with no trace of the other, switch west
and all I have is the west station at 59, again with no trace of the other.
Difficult to do much testing now its summer, but looking forward to the
winter season.
In the mean time I am going to replace the N/S reversible for a similar
install next.
I cant say of course this would work for everybody, but I seem to have got
away with it, my advice would be give it a try.
BTW the S meter on the Kenwood TS590s remains at S0-S1 in cw 500Hz and I
have the DX engineering Preamp in line as well (shack end). You assume
something is wrong until you hit a station calling who appears at 599+
Im pleased Theory is important but always worth a gamble not spending too
much time getting bogged down in it?
A picture tells a 1000 words so you can see a couple of pictures here of my
2 Parallel Beverages which break a few rules but work.
http://tiny.cc/fwdrew
Neil G0JHC
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