Topband: 160 metre vertical with 'top loading'

shristov shristov at
Wed Apr 27 03:36:04 PDT 2011

"Joe Subich, W4TV" <lists at> wrote:

> Any coil that shows a 60% decrease in current through
> it has a significant amount of unexplained loss.

A current decrease (meaning less current at one end that at the other)
is not a loss, and it's far from being unexplained.

It's caused by the standing wave, just like the current decrease on a straight wire.
The general nature of the standing wave is not altered by the fact
that the wire is wound insted of being straight.

Consider helically wound vertical antenna.
The current decrease here is from 100 % at the bottom to 0 % at the top,
but it involves no loss (on it's own), just the standing wave.


Sinisa  YT1NT, VE3EA

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