On Wed, 1 Feb 2006 07:00:50 -0600, "hasan schiers"
wrote:

Hi Richard,

Of course, when the inverted L was fed with both shield and center conductor
shorted, that is a short. But I also tried feeding just its center
conductor..and it was poor, as it should have been. I'm not saying that the
CW-80 center conductor only, brute force tuned was a great antenna, just way
better than I had any right to expect. It's not like 160 is like 10m, where,
when the band is up, nearly anything works. 160 is notorious for exposing
poor antennas.

Hi Hasan,

Maybe I just cannot visualize this. The inverted L is fed at the
bottom (at ground level) of a vertical rising wire that at some
distance up meets a horizontally running wire (or the same wire just
takes a horizontal bend out). It is fed with a coax whose shield
connects to a radial field (this is how I am interpreting your
antenna's description that I read, perhaps this is in error).

You also have an OCF Dipole that you have played with, but both
descriptions are woven so tightly together I will try to sort out the
jumble of descriptions.

All former connections remain as they were, but what I read next is
that

1) at the feed point you short the coax center conductor to shield,

OR

2) you short the coax center conductor to shield in the shack.

If (1), then that is simply a dead short which is confirmed by your
report "I got no band noise and very poor signals"

If (2), then you have a lot of RF being pumped directly into the
ground as per your description " My coax runs underground" and you
have left unsaid what you use for ground in the shack.

You also have an OCF Dipole fed with another coax (another
presumption). You feed this:

1) in the conventional way, as a dipole;

2) just with the center conductor (against shack ground?);

3) both the center conductor and shield (against shack ground?).

(1) results in no particular performance to write home about;

(2) or (3) presents far more DX opportunities and clearly more signal
than (1).

In any case, without a legitimate reference antenna, I am limited to "how
well do I get answered and at what distance" analysis and that's what I
tried to provide.

Try using a buddy who monitors you and the DX stations.

A test I would like to do sometime is to get a KW-80 trap, put it on the end
of the 80m L and extend the wire out for 160m resonance.

Reasonable plan.

Then I would have a
2 band inverted L and that would be a reasonable reference antenna. What has
kept me from this is I had a hard time finding the KW-80 traps...they were
out of stock. My other concern is since the 80m inverted L works so well, I
don't want to do anything to ruin its performance.

By your description, you already have a solution. There is unlikely
to be a better one than:

I was trying to get "something" for nothing with the CW-80 trick, and
succeeded beyond my wildest expectations. Nothing about my situtation could
allow anyone to duplicate what is happening here.

Strictly speaking, yes. However, the general solution you stumbled
across is fairly typical advice here - if we are speaking of the OCF
Dipole being fed with its elements shorted (or otherwise one half of
it as you seem to see it).

The only improvement I would see is to break the OCF Dipole's coax at
ground level and feed THAT shorted together with the coax coming from
the shack (the newly broken end). Attach the short to the center
conductor, and the shield of the coax from the shack going to the
ground field. When you want to use the OCF Dipole in the conventional
way, open the short, remove the ground and connect in the conventional
way. This could be reduced to a couple of switches at ground level.

Otherwise, what I see in the (2) - (3) OCF Dipole feed situation
above, is that you are also feeding a massive, lossy capacitor
(ground) along the way to the OCF Dipole. The (2) - (3) OCF Dipole
feed situation is simply a top loaded vertical which may enjoy some
harmonious relation with the tower in proximity.

Another possibility arises from the tower. If it is guyed, insulate
the guys about 1/3 their length down from the top, but make sure they
are connected at the top (Top Hat). Feed with a gamma match against
your ground field. The gamma wire will probably trace the same path
as your OCF Dipole line (2 to 5 feet out from the tower) and you will
need a few hundred picofarads to tune.

73's
Richard Clark, KB7QHC