>It really seems a waste of money on 80 and 160 unless you've got very long
>runs.
Disagree. Here's why: There are advantages to LDF4-50 etc.
regardless of the frequency and run length. That feedline is robust
in the physical sense. It can be installed and you are probably good
with it for a long time especially if you use and install the correct
connectors, but with the low bands, you can easily and safely
terminate the line at your transmitter and antenna by stripping it
back and connecting it to matching networks with brass or copper
clamps. The same is true in a shielded enclosure at the feed point of
a base fed vertical. Andrew and RFS hard line have lower loss
advantages even for less than 1 or 0.5 wave length runs that make them
desirable for QRP operating. Low power ops frequently evaluate line
in terms of _power handling capability_ but they should evaluate it in
terms of _power loss_.
Everyone using hardline enjoys the advantage afforded by the solid
copper shield. If the jacket is breached, the line still functions
whereas with lesser garden variety RG8 style coax cables, the jacket
is often softer and exposure of the braid is more likely. Water can
penetrate the line and rot it out over time.
The feedback I get from industry now is that the Andrew (Commscope)
line is no longer of the quality it once was. The shield is thinner
and more fragile. The RFS Cellflex line is found to be better, like
the old Heliax. I have no first hand experience though because my
supply of old LDF4-50 and LDF4-75 are not yet used up.
73
Rob
K5UJ
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