Here are some observations comparing broadside phased Beverage pairs and single
wires, and the effect of AZ alignment on target DX.
Does a 21 degree AZ change in Beverage orientation make a difference?
At my remote station I have 15 Beverage wires ranging from 750' to 1,000' long.
There are 3 single wire Beverages and 6 broadside phased pairs, each with 400’
inter-wire spacing.
All 8 major compass directions are covered. The original layout was the usual
45 degree alignment, 0 deg, 45 deg, 90 deg 135deg…. etc.
This summer I added a phased pair at 21deg for Russia, and northern Europe.
This new pair is exactly between my north (0 deg) and the 45 deg Europe pair.
I did this after modelling the broadside pairs and noticing how narrow the beam
width is. There was a 4 dB gap between the two patterns into N EU. (see my
YouTube vid referenced below for detail)
The conditions have been good this season into Europe so I've had the chance to
evaluate and compare these EU pairs.
There have been numerous times when north EU signals have been moderate to poor
copy on the “old” 45 deg pair, while jumping to Q5 copy on the new 21 deg pair.
There have been 3 occasions when some signals (especially EU Russia), have
gone from no copy (zero signal) to Q5. QSB can make antenna evaluation
difficult, but the waterfall display really helps to see the changes in SNR.
In a some cases QSOs would not have been possible without the new pair. Often
central EU is equal on both, and S EU is usually best on the old 45deg pair.
Of course all of this is dependant on a somewhat stable ionosphere with no path
skewing.
I’m sharing these results because I was somewhat doubtful that the new pair
would make much difference, but my testing shows that these arrays actually do
perform as modelled.
Modelling also shows that single wire Beverages have a noticeably more broad
forward lobe so they are more forgiving on target azimuth alignment…..
However, there is a real benefit to the enhanced RDF of the broadside pairs
over the single wires that I have observed.
On each of my phased pairs I have built a box which houses the in-phase
combiner and a relay. The relay can either select each wire separately, or
have the pair combined.
Using this system I can listen on the pair or instantly switch to either single
wire. On the waterfall it is quite obvious how the SNR of weaker signals pop
up when the pair is engaged compared to any single wire. On the weak ones this
is a QSO-no-QSO improvement.
These observations I’ve described are really ***ONLY noticeable*** (or
meaningful) on the real weak signals that are just bubbling at the noise.
Think “I can barely hear him”. If the signals are strong, then single wire,
broadside pair, off-azimuth pair etc. will all have good copy. This is true
with a lot of things to do with weak signal 160m improvement. Just like the
benefit of diversity RX….on strong signals its not a huge game changer, but
when those signals are on the edge of no copy, then these small improvements
start to make a difference. Same with APF.
Here is a YouTube video I made a while ago that shows the 4NEC2 modelling
comparing single wire Beverages and various spacing on in phase pairs and
explains why I added the second pair.
https://youtu.be/I-Q0JU3h--4 <https://youtu.be/I-Q0JU3h--4>
73, de steve ve6wz
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