Use of lattice line to feed dipole
 

Mike Coslo wrote:

So is the lesson that Ladder line sucks, or is it that we shouldn't
wash our ladder line with soap and water? 8^)

Although I discovered it long ago, I keep getting surprised at how many
people require a binary answer to any question -- is it good or bad,
sucks or doesn't suck, good or evil. Sure makes it easy for our would-be
politicians and their 15 second sound bite solutions to complex issues.
Hopefully at least some readers will consider what Owen said, that the
knowledge we've gained by this can hopefully help in the intelligent use
of the line. Those needing a binary answer should look elsewhere; there
are plenty of gurus who are more than happy to categorically state
positive but simple answers to just about any question. I use a coin,
myself, but each to his own.

Wes' and my measurements, and Danny's observations, can't be directly
applied to other situations. What they're meant to, and do, illustrate,
is that significant loss *can* occur under some circumstances, and
people who assume that twinlead or window line loss will always be low
can be very much mistaken.


Has anyone run tests on what "real" (open) ladder line does when you
spray it with wetting agent and water?

I don't think any result would be very meaningful, except to show,
again, that significant loss could occur under some conditions (which
I'm confident is the case). Those lines are often run with a very high
SWR. The effect of conductivity and/or loss across the insulators would
depend very heavily on the position and size of the standing waves. For
example, if the SWR is high and the insulators happen to be at or near
the voltage peaks, even a small amount of loss would have a major
impact. But on a slightly different frequency, the antenna's impedance
will change and the standing wave will move. If most insulators are near
voltage minima, you wouldn't likely notice even quite a bit of loss.
This effect would be most pronounced at higher frequencies where the
spacing between insulators might become a sizable fraction of a
wavelength, and not so pronounced at lower frequencies or with more
insulators. But the magnitude of the SWR would still make a major
difference.

Roy Lewallen, W7EL

Use of lattice line to feed dipole
 

Owen Duffy wrote:
... and aluminium wire braid can be a
disadvantage for solder-ability. (Cecil will correct the spelling if
you don't know what I mean!)

Owen, I can't pull Reg's leg about his spelling anymore
so now I'll have to pull yours.
--
73, Cecil http://www.w5dxp.com

Use of lattice line to feed dipole
 

Mike Coslo wrote:
And after a little discourse, we find out that Daniel sprayed
silicon spray of some sort on the line. That starts to make some sense
of why he had a problem with the line.

Maybe the moss liked it? Oh no! I just sprayed mine.
--
73, Cecil http://www.w5dxp.com

Use of lattice line to feed dipole
 

Danny Richardson wrote:
Well Mike, along my experience with ladder line there is also Roy's
and Wes's measurements. Based upon that, for me, I'm off the stuff.

Here in East Texas it rains much less than 1% of the
time. Rain is more often than not accompanied by lightning
during which my antenna is unplugged. Wet ladder-line is
just not a problem at my QTH especially since the only
horizontal portion of the run is under the eaves of my house
sheltered from the rain. The only portion exposed to the rain
is vertical and is usually being whipped dry by the wind.

But what about the water collected on the antenna wire itself?
--
73, Cecil http://www.w5dxp.com

Use of lattice line to feed dipole
 

On Sat, 23 Sep 2006 15:23:07 -0400, Mike Coslo
wrote:

Has anyone run tests on what "real" (open) ladder line does when you
spray it with wetting agent and water?

If you look at Wes' paper http://k6mhe.com/n7ws/Ladder_Line.pdf (table
1 on page 6) you'll see he did measure wet open line and reported "No
Change".

Danny, K6MHE

Use of lattice line to feed dipole
 

On Sat, 23 Sep 2006 21:29:39 -0400, Mike Coslo
wrote:

[snip]

Not trying to insult anyone here, Wes. Just trying to figure out what
is going on.

Uh huh.

My last comments on this are at the bottom of note 11 (except that I
won't be revisiting the subject) he

http://www.k6mhe.com/n7ws/

Use of lattice line to feed dipole
 

Danny Richardson wrote:
On Sat, 23 Sep 2006 20:58:12 -0400, Mike Coslo
wrote:


Aha! I was troubled with how you got mold or moss or anything to stick
to PE. I believe you are correct in your suspicions. One of PE's main
draws is it's inertness, and it is a real bear trying to get anything to
adhere to it. There is some possibility that the spray may have
contributed to what appears to be pitting on the line.

Certainly something troubles me with the idea that we can test
something under conditions where we apply chemistry to alter a
fundamental property of the material. (I'm referring to the wetting
agent tests) I believe that the tests do show adequately how ladder line
performs when covered with wetting agent and water. And that we don't
want to do that! ;^)

- 73 de mike KB3EIA -


Well Mike, along my experience with ladder line there is also Roy's
and Wes's measurements. Based upon that, for me, I'm off the stuff.

No problem Danny, although I'm not going to accept argument upon
authority. I give some extra weight to Roy and Wes's arguments, but
won't accept the arguments just because they say it's so. Should I?

My present open line setup is appears to be working fine. No
detectable moss, mildew or anything else that I can detect.

And I'll bet you didn't put anything on it?


One can go on forever trying to justify one way or the other, but thus
far, wet ladder or ribbon line has shown not to be the best route to
go - from three different sources. If you have something to the
contrary I certainly would be interested in hearing about it.

You coated your line with something it shouldn't have had on it. The
other line was coated with wetting agent, which some of us might think
was an artificial substance to be coating it with.

We can draw lessons from all this.


To each his own.

Indeed!

- 73 de Mike KB3EIA -

Use of lattice line to feed dipole
 

Roy Lewallen wrote:
Mike Coslo wrote:


So is the lesson that Ladder line sucks, or is it that we
shouldn't wash our ladder line with soap and water? 8^)


Although I discovered it long ago, I keep getting surprised at how many
people require a binary answer to any question -- is it good or bad,
sucks or doesn't suck, good or evil. Sure makes it easy for our would-be
politicians and their 15 second sound bite solutions to complex issues.

Hi Roy. I must have used the incorrect wording here. I'm pretty well
convinced that PE coated ladder line doesn't suck. Just one of those
email things I guess... 8^)


Hopefully at least some readers will consider what Owen said, that the
knowledge we've gained by this can hopefully help in the intelligent use
of the line. Those needing a binary answer should look elsewhere; there
are plenty of gurus who are more than happy to categorically state
positive but simple answers to just about any question. I use a coin,
myself, but each to his own.

I ask the questions that I do to find out what might be going on. I've
learned a few things here. one is that if you coat PE with some
substances, it will alter it's properties.

Another is that there is a measurable difference in loss when a PE line
is coated with a wetting agent, which is needed to evenly (read wet)
coat PE with water. Some portion of this could be applicable to
non-wetted PE coated line.


Wes' and my measurements, and Danny's observations, can't be directly
applied to other situations. What they're meant to, and do, illustrate,
is that significant loss *can* occur under some circumstances, and
people who assume that twinlead or window line loss will always be low
can be very much mistaken.

However, some *are* applying them to other circumstances.


Has anyone run tests on what "real" (open) ladder line does when
you spray it with wetting agent and water?


I don't think any result would be very meaningful, except to show,
again, that significant loss could occur under some conditions (which
I'm confident is the case).

Agreed.

Those lines are often run with a very high
SWR. The effect of conductivity and/or loss across the insulators would
depend very heavily on the position and size of the standing waves. For
example, if the SWR is high and the insulators happen to be at or near
the voltage peaks, even a small amount of loss would have a major
impact. But on a slightly different frequency, the antenna's impedance
will change and the standing wave will move.

Good point

If most insulators are near
voltage minima, you wouldn't likely notice even quite a bit of loss.
This effect would be most pronounced at higher frequencies where the
spacing between insulators might become a sizable fraction of a
wavelength, and not so pronounced at lower frequencies or with more
insulators. But the magnitude of the SWR would still make a major
difference.

I would assume then that the big difference is the continuous coating of
the PE then?

Thanks for the feedback, Roy, I'm here more to learn than to argue.
(perhaps Quixotic?)

-73 de Mike KB3EIA -

Use of lattice line to feed dipole
 

Richard Clark wrote:
On Sat, 23 Sep 2006 21:29:39 -0400, Mike Coslo
wrote:


I'd wager his mold, moss, or mildew problem has more to do with his
unapproved use of chemistry on the line.


Hi Mike,

This doesn't explain mold, moss, or mildew that naturally occurs under
very similar circumstances.

Mebbe, Richard. I hate to sound skeptical, but it actually grows on
untreated PE? I mean PE's inert behavior and the difficulty of anything
sticking to it are one of the reasons that companies like Nalgene (okay,
Nalge) use it.

- 73 de Mike KB3EIA -

Use of lattice line to feed dipole
 

Cecil Moore wrote:
Mike Coslo wrote:

And after a little discourse, we find out that Daniel sprayed
silicon spray of some sort on the line. That starts to make some sense
of why he had a problem with the line.


Maybe the moss liked it? Oh no! I just sprayed mine.


Just so it isn't unhealthy for the anoles! 8^)

- 73 de Mike KB3EIA -