Well, if you ask ten hams a question like you did you will get 11 opinions -
because one will change after hearing the others...
So, my opinions are:
Yes, running a second beverage parallel and close to the first will cause
significant interaction... The accepted rule of thumb is that minimum lateral
separation between Beverages that are at less than a 45 degree angle should be
at least their height above ground... In my opinion it should be significantly
more than that... If you check the published Beverage installations you will
find they all (including me) make wires cross at a fairly acute angle and not
run nearly parallel...
Next, there is not a nickel's worth of difference between the transformers
wound by the various vendors...
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The difference is that the transformer's primary winding impedance (and coax
turns ratio) needs to match to the impedance of your Beverage wire as
installed... (repeat this to yourself ten times as it is the key to
understanding life, the universe, and everthing - well that and 43)
***********************************************************************************
I have not used KD9SV's transformers... I have used K1FZ, DX Engineering, and
multiple ones of my own winding - both single toroid and binocular core...
After a massive lightning storm exploded all but one transformer in my Beverage
array a few months back - an amazing display of lightning strokes slashing
across my South 40 like Irish River Dancers - I am currently using DX
Engineering boxes- 2nd day delivery - both the single direction and the
reversibles... I feel they work just fine and do not see/hear any difference to
my hand wound except their SS enclosures and hardware are first rate compared
to my usual Tupperware and Margerine containers.....
On ladderline versus twisted pair - I am opinionated - I don't use either...
Ladderline is a pain in the butt to keep up if you have any wind at all...
Ladderline is heavy, it has amazing wind resistance and flails and flops like a
wounded fish in a strong wind... It takes double the amount of poles to run
ladderline compared to anything else..
And a twisted pair annoys my sense beauty... I run two parallel wires, no
twist, nicely tensioned...
I use aluminum fence wire - 17 gauge - it is cheap and light and you can
tension it with two fingers. It runs nicely with a pole every 100 feet. and it
works.. My reversibles use 4 inch spacing... A 450-600 ohm transformer seems
to about right...
I have not tried using 2 spaced wires as a single wire... It will work, but
there may be subtle problems... I am not in favor of giving Murphy an
unecessary opening for mischief...
denny / k8do
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