> And it doesn't matter if there's a preamp at the feedpoint.
It matters in one case ... if the preamp, combiner, relay switching
network is powered via the coax. If the coax is aluminum foil/braid
and copper clad steel or copper clad aluminum, the resistance can
introduce enough DC losses that the available power is insufficient
to operate the remote equipment properly.
73,
... Joe, W4TV
On 8/11/2023 2:04 PM, Rob Atkinson wrote:
Okay thanks for the explanation.
Rob
K5UJ
Depends on the efficiency of the antenna and whether there's a preamp at
the feedpoint of those with low efficiency. It doesn't matter for higher
efficiency RX antennas like Beverages, or where local noise levels are
fairly high. And it doesn't matter if there's a preamp at the feedpoint.
Mostly it can matter for TX antennas.
73, Jim K9YC
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