On 10/9/2011 3:33 PM, John K9UWA wrote:
> can you tell me why one would NOT want to use the common variety of a
> RG-6 that has a few strands of braid.. and foil + foam insulation and
> the usual single wire center for an Antenna on 160 meters?
1) LOSS. Significant if it's a long run for flimsy shields. Also,
copper clad steel is pretty lossy on the lower bands as compared to
solid copper or copper clad Aluminum. If you're only going 25 ft, it
doesn't matter.
2) SHIELDING If you've got much RF noise around you, you could benefit
from a much more robust shield that what's on the cable you describe,
especially on an RX antenna. Shielding is strongly dependent on the
resistance of the shield, and foil shields aren't worth much until you
hit VHF. BTW -- one thing that can be less than wonderful about those
crimps is the resistance (and reliability) of the shield connection.
3) Define "almost nothing." :) I know guys (N6LF is one) who will go
to extremes for less than half a dB when they're already maxed out on TX
power and everything else in their system. I certainly agree that the
loss in 25 ft of almost any coax on 160M doesn't matter.
73, Jim Brown K9YC
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