I agree with all of this.
AND -- a point that is often missed is that below about 500 MHz,
transmission line loss is entirely due to I squared R. The only benefit
of a foam dielectric is to allow the center to be larger for a given
shield size. THAT'S why foam coax has lower loss below 500 MHz. Those
who understand this use hard line for long runs from the shack to the
top of a tower (or to the bottom of a crank-up) and a RG8-size coax for
stuff that has to move.
As to high dipoles -- I use them for 80 and 40, and feed them with a
good RG11. Tension is about 100#, supplied by water jugs filled with dry
sand on one of the two support ropes that go through pulleys in the
trees that hold them.
73, Jim K9YC
On 8/24/2017 9:28 AM, Clay Autery wrote:
Overkill? Depends on your goal... Mine is to NOT have to do
unnecessarily frequent maintenance/replacement. And a wet cable is
unnecessary.
Wasted Money? I bout the "-DB" stock I used last for less than a dime's
difference. As it will likely last TWICE as long, it was a bargain.
Heavier? Insignificant except for MAYBE wire dipoles with no middle
support... Use better engineering or bigger dipole wire and pull more
tension. Or don't worry about getting it perfectly flat.
Unsuitable? Matter of opinion even in your subset of wire antennas.
I will reiterate what my Dad taught me:
"If you cannot afford to do <insert task> once, you certainly cannot
afford to do it twice."
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