[Antennas] Ladder line use with beams

[Steve L.]

Greetings from the soggy northwest,

I've used commercial 450 Ohm windowed ladder line to
feed HF quads with great success. You do have to
re-tune between wet and dry and little, this is true.
I've connected the feedpoints of three concentric
quads (10/15/20) together and fed them with a single
line, too. (This should bring out the flame trolls,
eh?!)

I cut every other spacer out of the line where it runs
horizontally and rub a high quality automotive paste
wax on it - this greatly reduces the wet-effect and
lasts a long time.

Where the line runs vertically the rain runs off
nicely and I don't cut every other spacer out but I
still wax it. Yes, I look stupid doing it.

Using real air-insulated balanced line virtually
eliminates the wet-effect but you've gotta MAKE 250'
of the stuff, right? Dang. Maybe this is a good
fireside winter thing to do at night.

I've used 1/2" OD CPVC for spacers for 4" spaced
phasing lines (which can't change with water!). Notice
it's 1/2" OD, most PVC dimensions are ID and it's CPVC
used for potable and hot water in mobile homes and
stuff. Pretty lightweight and super easy to work with
- kind of a tan color, not white. Don't cut it with a
hacksaw, use a PVC-cutter hand tool made just for this
- gives a clean cut. I say this because I just learned
it this summer and I still feel stupid.

73, Steve N4SL Machias WA CN88xa

--- Sandy and Kees Talen <windy10605@juno.com> wrote:
> I'd like to ask some opinions on this.....	
> 
> I have a 250ft run to the HF beam and typically
> drive at 
> 150W or less. Since low loss (and low cost) is
> desired,  
> I settled on a long run of 450 ohm ladder line
> through the 
> trees, smooth long radius bends (most through
> radiator 
> hose where it touches something, etc. An antenna
> tuner 
> is used at the Tx/Rx end.
> 
> At the tower, it runs through pieces of PVC spaced
> 12" out 
> from the tower with plastic stock and  20 ft apart
> (55ft tower). 
> At the top it runs through a "loop" of smaller
> heater hose to 
> get around the rotor and is tied directly to the
> beam. Seems 
> to work fine. I was going to use a 9:1 or at least a
> 4:1 balun 
> at the beam end (or at least so I could get around
> the rotor 
> with coax) but figured that the mismatch wouldn't
> affect
> anything because of the low IR loss in the ladder
> line and 
> I could always match to the Tx with the tuner.....so
> I tied it 
> directly to the beam. There may be some substantial
> voltages developed at the beam end (and ?) because
> of the 
> mismatch.  What else do I need to look for ?
> 
> Any ladder line is affected by moisture, I've heard
> that open 
> (4"+ spacing) is not. Any verification of this ?
> What is 
> a good cheap spacer ? ...light, cheap, easy to
> rework, stable, 
> easy to attach, strong, low wind resistance. 250 old
> BIC pens ?
> ...just kidding. I'm not boiling wood sticks in hot
> parafin with 
> PVC available. 
> 
> Comments ?
> 
> 
> 73s  Kees K5BCQ
> - - - 
> 
> Your moderator for this list is:
> Larry Wilson KE1HZ antennas-owner@mailman.qth.net
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