On Thu, 16 Aug 2007 18:58:26 -0400, "Rick (W-A-one-R-K-T)"
wrote:

On Thu, 16 Aug 2007 12:46:26 -0700, Richard Clark wrote:

Doubling the dimensions of:
http://home.comcast.net/~kb7qhc/ante.../Cage/cage.htm
would satisfy 3/4ths of your spectrum requirement

At the risk of sounding negative again, is it OK if I point out that one
of my early needs involved NVIS operation (it's in one of my early posts),
and verticals in general and cages in particular aren't really suitable
for that?

A review of my response at that time offered a dipole of similar
construction in its place. It doesn't take much math (or rotation) to
shift from monopole to dipole.

There is NOTHING about a cage that makes it unsuited for NVIS. It may
be intractable, but that goes with the turf.

I wonder though about why this is so agonizing. If you work MARS/CAP,
it would seem that solutions would be there in pile-ups for the QST
tossed into radio land. That, or everyone is wandering in the
wilderness.

It is not like I haven't seen these questions about MARS/CAP asked
before, but most were satisfied with the air-cooled resistor and
didn't show much interest in efficiency (what for? there was no real
choice in the matter without several kilobucks of investment anyway).
Go to Salvation Army and buy toasters for lossy loads (they come in
1KW values for $5).

BalUn? When you characterize allowable efficiency as being between
-2dB and -18dB, then you don't even need a BalUn anymore. It's going
to cost you $1000 to rotate it (whatever "it" is). And if crisis (I
gotta hear them and they gotta hear me) drives the design, then you
have to open the wallet. Does anyone else in MARS/CAP get by with
less? In a dozen years I haven't seen a single post by one to claim
they do (or admit they couldn't hear or be heard).

You are going to have several many antennas. None are going to be
whole solutions. Some are going to be slow to tune. Some may never
tune. Some may never be heard. Propagation will be a cruel arbiter.
Guarantees won't be honored. This is pretty much the same fate in the
Ham bands, and out of band frequency doesn't alter this reality very
much.

Decide to build a farm efficiently. Select ranges of frequency
suitable to octaves, not decades. Point immovable antennas towards
your expected traffic. Or if you are filling in a network's uncovered
areas, point them in those directions (that is what a network is for,
isn't it?).

I taught HF/VHF/UHF comm systems in the Navy and served as senior
Petty Officer in CIC. There is no such thing as a single solution.

73's
Richard Clark, KB7QHC