So "Swarming" is really the term for that? I could use that.
Sometimes that phenomenon is real comedy material. I can just
see Laurel and Hardy putting up a short wave antenna......

"swarming" hmmmmm, like you disturbed a hornets nest eh?

Now that I think of it, the actual physics behind "swarming"
would be pretty darn sophisticated stuff.....


Bill (aka Zeno, aka, etc...)


'Doc wrote:

Zeno,
"Swarming" means that because of the 'memory' of the wire
used to make the 'twin lead', when it's turned loose from
whatever you fixed it to to build it, it tries to assume it's
former shape. Usually results in a 'rat's nest' of wire in
a not so compact ball, LOL! Not really something to waste a
lot of worry on, just be aware that it can happen.
'Doc

Doc,

Would this be a good reason to use solid core copper wire?

After tying one end of my ladder line to a short (PVC) pole at
the house roof peak (this is to keep it high and away from some
other lines), I need to carefully arch (arc) it around and into
the side of the house (or into a modified "window" that
ventillates the attic space up there. I might use a "stick" or
something to make sure the ladder line stays where I want it
here. The ladder line at this point has to go through a space
between a cable tv and a telephone line. If the ladder line is
kept in place, it will be 2-3 feet away from the other lines
which are perpendicular (and thus only in proximity at a one
point).


It is because of these other lines that I perhaps might have to
consider other alternatives, but I thought I would first try the
idea of running the ladder line all the way into the station in
the house. If there is a problem with interference, then I might
have to consider the system, I have seen mentioned, where you
run double coax lines into the house for the last section with
the shields tied together (anyone actually tried that, does that
work well, any problems, etc.?)



My point being that solid core wire is easier to "mold" into
shape. My only concern is that sometimes solid core could break
if there is a repetitive friction type bending stress along the
way (wind, or who knows).

Zeno



'Doc wrote:

Zeno,
"Swarming" means that because of the 'memory' of the wire
used to make the 'twin lead', when it's turned loose from
whatever you fixed it to to build it, it tries to assume it's
former shape. Usually results in a 'rat's nest' of wire in
a not so compact ball, LOL! Not really something to waste a
lot of worry on, just be aware that it can happen.
'Doc

Any reason not to feed each wire through the wall using those old
time ceramic insulators with the hole down the middle, you know,
those 4 or 5" long while tubes that were used in the knob&tube era
of electrical wiring. Since I would be making my own feed line
here, I could rejoing the pair on the other side of the wall and
continue with my spacers until I reached the ceiling, and then to
the process again, eg. putting each wire thru its own tube and then
continuing with the spacers on the other side.

It is either this or using that idea of double coax feed with the
coax grounds connected to each other at one end and grounded to the
tuner (?), anyone have sucess with this method of coming into the
shack via balanced lines?

Zeno

'Doc wrote:

Larry,
Boy, are you gonna have fun! As Cecil said, spacing isn't
all that critical. Use whatever you can find enough of, to make
the 'spreaders', as long as it's not conductive it should work.
The simplest way to feed ladder line through a window is to
make a 'spacer' board to fit in the window. Drill a couple of
holes in the board, the correct distance apart, feed the line
through the holes, 'hot glue' in place (or however you can get
it to stay put. Have to remove the screen...
'Doc

PS - The real 'trick' is to keep the line from 'swarming' on
you when you finish.

Zeno,
No reason why it wouldn't work, just use the normal care
in selecting a 'spot' in the wall that doesn't hold any
other wiring, etc. Using feed-throughs like that is sort of
'permanent', can't remove it without repairing the holes.
The board in the window thingy isn't 'permanent', just take
it out of the window and replace the screen (if any). The
choice is your's and your 'significant other's (probably more
her's, than your's, right?)...
'Doc

I tried practicing making some diy ladder line with a couple of
spacers and a variety of wi stranded #12, and solid #12, and
then solid #14 (all insulated).

I think I am going to pass on this process. The only way I can see
this homebrew ladder line holding its shape (spacing configuration)
is to keep it under quite a bit of tension, a situation which may
not actually be appropriate to my specific installation parameters
here.

I am now thinking: how bad could those commercially manufactured
window lines be?

Any recommendations on a specific type of commercially made window
(ladder) line? I see that it comes in a variety of configurations
and slight differences in Z.

This feed line will be for a full wave 160m loop.

I am not all that convinced that the effects of weather on this
commercially available balanced line would be that much more
negative than what it would be with any homebrew line I could
construct.

I am under the impression that homebrewed ladder line should strive
to have as few spacers as possible, eg. 3' for straight runs, 1-2'
for curves. Using these guidelines it seems like what I would come
up with would not maintain a precise spacing and the temptation
would be to use a spacer at every foot. Wouldn't it be undesireable
to use so many spacers?

Somebody out there must like commercial window ladder line?

Bill

'Doc wrote:

Larry,
Boy, are you gonna have fun! As Cecil said, spacing isn't
all that critical. Use whatever you can find enough of, to make
the 'spreaders', as long as it's not conductive it should work.
The simplest way to feed ladder line through a window is to
make a 'spacer' board to fit in the window. Drill a couple of
holes in the board, the correct distance apart, feed the line
through the holes, 'hot glue' in place (or however you can get
it to stay put. Have to remove the screen...
'Doc

PS - The real 'trick' is to keep the line from 'swarming' on
you when you finish.

How close do the spacers need to be placed in reality?

http://www.w7fg.com/ant.htm

How close do these spacers appear to be.

Bill

zeno wrote:

I tried practicing making some diy ladder line with a couple of
spacers and a variety of wi stranded #12, and solid #12, and
then solid #14 (all insulated).

I think I am going to pass on this process. The only way I can see
this homebrew ladder line holding its shape (spacing configuration)
is to keep it under quite a bit of tension, a situation which may
not actually be appropriate to my specific installation parameters
here.

I am now thinking: how bad could those commercially manufactured
window lines be?

Any recommendations on a specific type of commercially made window
(ladder) line? I see that it comes in a variety of configurations
and slight differences in Z.

This feed line will be for a full wave 160m loop.

I am not all that convinced that the effects of weather on this
commercially available balanced line would be that much more
negative than what it would be with any homebrew line I could
construct.

I am under the impression that homebrewed ladder line should strive
to have as few spacers as possible, eg. 3' for straight runs, 1-2'
for curves. Using these guidelines it seems like what I would come
up with would not maintain a precise spacing and the temptation
would be to use a spacer at every foot. Wouldn't it be undesireable
to use so many spacers?

Somebody out there must like commercial window ladder line?

Bill

'Doc wrote:

Larry,
Boy, are you gonna have fun! As Cecil said, spacing isn't
all that critical. Use whatever you can find enough of, to make
the 'spreaders', as long as it's not conductive it should work.
The simplest way to feed ladder line through a window is to
make a 'spacer' board to fit in the window. Drill a couple of
holes in the board, the correct distance apart, feed the line
through the holes, 'hot glue' in place (or however you can get
it to stay put. Have to remove the screen...
'Doc

PS - The real 'trick' is to keep the line from 'swarming' on
you when you finish.

zeno wrote:
http://www.w7fg.com/ant.htm

How close do these spacers appear to be.

Using a tape measure, they appear to be 21 inches apart.
--
73, Cecil http://www.qsl.net/w5dxp



-----= Posted via Newsfeeds.Com, Uncensored Usenet News =-----
http://www.newsfeeds.com - The #1 Newsgroup Service in the World!
-----== Over 100,000 Newsgroups - 19 Different Servers! =-----

On Tue, 20 Apr 2004 06:23:13 GMT, zeno wrote:

Any recommendations on a specific type of commercially made window
(ladder) line? I see that it comes in a variety of configurations
and slight differences in Z.

This feed line will be for a full wave 160m loop.

Hi Bill,

You repeatedly characterize this as 160M and given the size and height
- Why do you think you need ladder line when it will in all
probability fit quite nicely into a coax?

In free space, it may show as much as 140 Ohms R; however, within the
cold embrace of earth only 50 feet away, you will barely muster 35
Ohms at resonance.

73's
Richard Clark, KB7QHC

Hi Richard,

My beginner's understanding is that I would have a better multi-band
antenna utilizing a balanced feedline than with coax. I had seen a couple
of recommendations by doing internet searches. Several operators spoke
highly of the ~540' loop with balanced feed. I have a nice old 250W
Johnson matchbox on hand. Again, my beginner's understanding, the more
wire=the better, so I figured this long loop would be a good antenna for
"all" bands.

I am just now setting up a station for the first time. I need to think I
know what I am doing long enough to simply put something into action for
fear I will spend forever in a complex endless decision making matrix. I
enjoy trips to the hardware store and the junkyard, I haven't even been
on the air yet......(or at least since 1953....).

I figure antenna concerns are first, a good ground, then I need to think
about some serious equipment. This can be a bit overwhelming. Ihis next
Sat. I will be going to a local hamfest (my first one), hopefully to meet
some locals and make friends (mentor's, Elmers, etc.), also to track down
the guy with the bow and arrow who can get a line up my Eucalyptus tree
(165'+) for another possible antenna in an alternate shack on the
property......

actually, now that I think of it, my whole involvement in ham radio at
this moment (besides the fun of studying for the exams last month) is
dreaming of antenna farm.

just the other night while listening to some local maniacs on 3840, now I
realize I need to get my Extra if I want to be able to chime in at that
frequency.....those guys last night almost shattered my naive expectation
that hams are always gentlmen, a pursuit of integrity I personaly fully
intend to promote in my own operating demeanor. Apparently there is some
"famous" AM talk show host involved with that little late night net.....
shame on them....

Great, now I have a shopping mission.....go out and buy the Extra exam
book.....I do actually enjoy studying and learning.....

Now....a trip to the junk yard to find an old fashion DPDT Knife switch
I can mount on the wall so I can switch my incoming balanced line from
the Johnson to the Kenwood tuner....


help!.....


73

Bill (KG6UHM)



Richard Clark wrote:

On Tue, 20 Apr 2004 06:23:13 GMT, zeno wrote:

Any recommendations on a specific type of commercially made window
(ladder) line? I see that it comes in a variety of configurations
and slight differences in Z.

This feed line will be for a full wave 160m loop.

Hi Bill,

You repeatedly characterize this as 160M and given the size and height
- Why do you think you need ladder line when it will in all
probability fit quite nicely into a coax?

In free space, it may show as much as 140 Ohms R; however, within the
cold embrace of earth only 50 feet away, you will barely muster 35
Ohms at resonance.

73's
Richard Clark, KB7QHC

Hi Richard,

You remind me that I do not understand something. Let's say the
characteristic impedance of this 540' loop is in the neighborhood of 140
ohms in free space, or even as you say closer to even 35 ohms in reality.
Your point was, if I understand correctly, that this is in the ballpark
of 50ohm coax and you suggest it can just as easily be fed into the coax.

But I thought that coax is unbalanced and the point was to go with a
balanced feed line?


I guess I am not understanding the relevant differences between balanced
vs. unbalanced feedlines, and getting the impedance of the the
transmission line close to the impedance of the antenna.

I thought the point of my striving to use balanced ladder line was to
somehow gain something that would be compromised by using coax. I thought
that the the ladder line which might be 488 ohms say is still going to be
a better feedline than using the 50ohm coax. The coax would still then
require a balun, correct? (a 1:1 banlun?).


It is sites like this: http://www.cebik.com/par.html that tend to get
one thinking about this whole diy approach.

My reading and gleaning of websites has me of the opinion (at this point)
that the balanced line with this long loop is better (multi band) than to
feed it with coax.

I believe Cecil has already explained this in terms of the wide range of
actual resistance that may be encountered multi band. (hey, I am just now
learning to talk this lingo....just barely know what I am talking
about....operating intuitively, and with the kindness of strangers.......



Zeno (aka Bill) KG6UHM for the moment.....



Richard Clark wrote:

On Tue, 20 Apr 2004 06:23:13 GMT, zeno wrote:

Any recommendations on a specific type of commercially made window
(ladder) line? I see that it comes in a variety of configurations
and slight differences in Z.

This feed line will be for a full wave 160m loop.

Hi Bill,

You repeatedly characterize this as 160M and given the size and height
- Why do you think you need ladder line when it will in all
probability fit quite nicely into a coax?

In free space, it may show as much as 140 Ohms R; however, within the
cold embrace of earth only 50 feet away, you will barely muster 35
Ohms at resonance.

73's
Richard Clark, KB7QHC