RadioBanter - View Single Post

October 9th 04, 08:28 AM

On 09 Oct 2004 06:37:43 GMT, ospam
(Theplanters95) wrote:

With the power company feedline coming in at the front (away from feed point.
would a "U" shape (that is a loop with a gap around the power line) work. I
think that I just realized the answer. It would or could cause an unbalanced
situation which could lead to all sorts of problems like RFI, unable to tune,
etc....

Hi Randy,

All of this is actually a long shot - very unlikely. If it DID happen
you have a scapegoat, but RF is not that delicate a flower rent by the
hurricane of speculation. In other words, try it to see if you have
a problem. You will spend far less trying compared to the time
worrying about the possibility.

I am also thinking of running the loop along the backside of the house and
then instead of continuing to run along the side of the house, run the wire to
an old unused billboard (about 20 or 30 feet high) and then from the billboard
back along the front of the house, and then instead of along the side, run it
to a tree (the only one on my property) and then back along the side of the
house. The feedpoint would be on the backside about 1/4 or 1/3 from the tree
side.

Now you are cooking with gas. Imagination is kicking into high gear
and invention is working with real possibilities.

An idea, if, I use the 2 of the pipes as additional supports placed at the top
of the side eaves , I could run a wire from the tree over the roof to the
billboard, sort of an inverted V or a droopy end dipole with a slight bend on
one side. And if the pipes are placed just right, then I would not be running
a wire under a power feed line, like the loop on the eaves. It would be random
length, and feed about 1/3 or so from the tree end, unless I got more
ladderline. Total length about 60 or 80 feet at about 20 or 30 foot sloping
down to about 10 or 15 feet at the tree. Let's see, a random length dipole in
the clear (by a few feet), should out perform a loop under the eaves? Easier
matching, antenna in the clear, less RFI, better for NVIS and DX. Maybe a
better antenna?

Whoops! Backsliding to that familiar nemesis of "a solution in search
of a problem." You are trying too hard to put those tubes to work -
use the abandoned sign. Dare I say it is a "sign?" The metaphor is
certainly not lost on you is it? ;-)

Can an OCF dipole be feed with ladderline?

It typically is and it typically is fed with coax too - howabout that
for political answer - sorry, watching too many debates. We taped the
soap opera when we went out to listen to Mort Sahl here in town. Mort
is getting on in age (wish I could have caught his act at the Hungry I
in Frisco) but he is as sharp as a tack still... and then we got back
for the punch and judy show as a retread. I wanted to throw the
remote at those two monkeys. Politics is a sure argument against
Darwin (evolution caught in a time warp).

OCF guarantees Common Mode for any feed. It is up to you to force a
new balance.

What is the best way to run ladder line over asphalt shingles?

The asphalt isn't a problem, it's the water and crud that comes with
the rain that bridges the wire. Use coax for short runs because you
would need standoffs (like they used to use for TV twin line back in
the old days) but you are back to loss due to water and crud that
comes with the rain that bridges the wire (get the idea?).

Or just simply ignore the loss of the water and crud that bridges the
wire (or ignore the loss of coax) and get on with the fact that no one
can tell the difference with WHAT you use (come what may, rain OR
shine).

One of the supreme ironies is that most folks achieve their greatest
improvements with very little work, and then they have to struggle to
double that performance gain - and then they have to quadruple that
heroic effort to double it again. Ever hear about the problems of
Sisyphus?

73's
Richard Clark, KB7QHC