Force 12 spec depends upon 100 feet of coax:
> Sounds like their BW quote depends on there being enough
> loss in the feedline to achieve it.
Some years ago, Dave Leeson, now W6NL posted the
explanation here on Tower Talk. The length of line creates
a double tuned transformer which per theory does, in fact,
increase the "system" bandwidth. It is NOT added loss, it
is a form of matching transformer. I do not recall the details,
but suppose they can be found in the archives. These
posts were at least 5 years ago, perhaps even further back.
Dave is a PhD in EE, and has written many articles/books
in the tech literature; so presume he knows about what he
suggests to be true!
And, yes, I would guess that the "transformer" of a 100 foot
coax would only be optimum for a particular band area;
probably on 15 meters if I remember anywhere near correct, hi.
73, Jim KH7M
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