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THE AM BULLETIN BOARD => Technical Forum => Topic started by: aa5wg on October 30, 2012, 09:31:04 PM



Title: Open Wire Spreader
Post by: aa5wg on October 30, 2012, 09:31:04 PM
Who has great home made open wire speader that works without glue, extra twisted wires, UV protective
and is mechanically sound?

At present I am leaning towards a single cable tie passing through the center of a 1/4 inch UV black pvc pipe that will hold the two wires tight by zipping the tie tight with a pair of pliers.  

Thus far the head of the cable tie dose not bend easily to conform to the wire O.D.  I have a different type of cable tie on order to test.

I am not sure this will work any better.

Looking forward to hear and see pictures of your better ideas.

Chuck


Title: Re: Open Wire Spreader
Post by: K3YA on October 30, 2012, 10:08:49 PM
Who has great home made open wire speader that works without glue, extra twisted wires, UV protective
and is mechanically sound?

I can't meet all your requirements.  However the best spreaders that I ever came up with I made over 25 years ago and are still going strong.  Just survived a hurricane.

They are 1/2 hardwood dowel rod boiled in paraffin.  They need the twisted wires that you don't want.  The wood dowel is available in any hardware store.  The paraffin is wax toilet seals melted on a hot plate.  Melt the wax outside in case it catches fire!  Solder a small loop of wire to hold it in place. 

It may be more work then you want to make but it will last forever and is very light weight.  Sorry about the blurry photo.

(http://imageshack.us/a/img32/9610/picture023or.jpg)


Title: Re: Open Wire Spreader
Post by: aa5wg on October 31, 2012, 08:51:51 AM
K3YA:

Thanks for the information on your spreader.  At one time I used spreaders like these.
However, I am looking for something that can eliminate the extra twisted wire that holds
the spreader in place. 

73,
Chuck


Title: Re: Open Wire Spreader
Post by: W7TFO on October 31, 2012, 11:09:02 AM
One problem with pipe or hollow spreaders is they get to fill up with conductive gunk and dirt over time.

73DG


Title: Re: Open Wire Spreader
Post by: aa5wg on October 31, 2012, 12:34:31 PM
DG:

Good point.

Chuck


Title: Re: Open Wire Spreader
Post by: W3GMS on October 31, 2012, 01:52:46 PM
I use 3/8 Lucite solid rod stock cut in 6" lengths.  Been up for 30 years without a problem.  Does use the tie wires like Charlies, K3YA spreaders.  I used 14 gauge solid copper magnet wire for the feeders which are 125' in length.  Feeds a 260' center fed up 60'.
 
Joe, W3GMS


Title: Re: Open Wire Spreader
Post by: aa5wg on October 31, 2012, 02:22:09 PM
HI Joe:

Thanks for your input.  Sounds like you have a nice antenna.

Chuck


Title: Re: Open Wire Spreader
Post by: W7TFO on October 31, 2012, 02:24:03 PM
I've seen plastic rod, cut to length, with the wire captured by heating it (the wire) up and 'melting' it into the ends of the rod.

73DG


Title: Re: Open Wire Spreader
Post by: W1AEX on October 31, 2012, 04:45:50 PM
A number of people up here in the Northeast are using Fi-Shock electric fence insulators. I used a hot glue gun to fasten the feedline wires but someone more clever than me came up with a simpler method. The insulators are hollow, so they slide a long zip tie (11 inch zip tie works fine) through the center and then capture one of the feedline wires and double the zip tie back through the insulator. They then capture the other feedline wire and pull the zip tie tight with pliers. It's very secure, lightweight, offers little wind resistance, doesn't require re-tuning when wet, and it's UV resistant as long as you use UV resistant tie wraps. The Fi-Shock insulators are about 20 bucks per box of 200 at Tractor Supply outlets or when ordered online.

Rob W1AEX


Title: Re: Open Wire Spreader
Post by: W3GMS on October 31, 2012, 05:01:18 PM
A number of people up here in the Northeast are using Fi-Shock electric fence insulators. I used a hot glue gun to fasten the feedline wires but someone more clever than me came up with a simpler method. The insulators are hollow, so they slide a long zip tie through the center and then capture one of the feedline wires and double the zip tie back through the insulator. They then capture the other feedline wire and pull the zip tie tight with pliers. It's very secure, lightweight, offers little wind resistance, doesn't require re-tuning when wet, and it's UV resistant as long as you use UV resistant tie wraps. The Fi-Shock insulators are about 20 bucks per box of 200 at Tractor Supply outlets or when ordered online.

Rob W1AEX

I like the zip tie approach Rob.  Very clever with that method of holding the wire to the spreader.  I had never seen that one before.

Joe, GMS


Title: Re: Open Wire Spreader
Post by: W1AEX on October 31, 2012, 05:08:24 PM
Hi Joe,

Yes, I wish I could take credit for it!  :)

I think Bob K1KBW or Blaine N1GTU came up with that one. If I ever have to re-do my feedline I will definitely do it that way.

73,

Rob W1AEX



Title: Re: Open Wire Spreader
Post by: aa5wg on November 01, 2012, 10:03:13 AM
Hi Rob and all:

I was going to do exactly the same thing you did with the Fi-Shock except use small O.D. schedule  80 black UV pipe (.540 inches O.D. and .282 inches I.D.) that is rigid.

How rigid are those Fi-Shock 4 inch insulators?  Do they flex or bend?  Dose Fi-Shock make a non-ribbed smooth version?

Thank you.

Chuck


Title: Re: Open Wire Spreader
Post by: Detroit47 on November 01, 2012, 11:13:53 AM
I like these I saw them at Dayton. http://www.73cnc.com/product_p/ls100.htm

John N8QPC


Title: Re: Open Wire Spreader
Post by: aa5wg on November 01, 2012, 12:02:20 PM
John:

Have you used the Ladder Snap speaders?  Their add states used with #14 wire.  Do you know if they can be used with larger diameter wire, i.e. #12 and #10?

Chuck


Title: Re: Open Wire Spreader
Post by: K6IC on November 01, 2012, 12:55:29 PM
AEX Rob,  your feedline looks very sporty!

Chuck,  OWL has very low loss,  as you know.  Why would you want to use larger guage wire than #14 AWG?   Is that just for durability?  Unless the antenna you are attaching the OWL to is center-supported,  #12 or #10  would be HEAVY.  Just opinions,   GL Vic


Title: Re: Open Wire Spreader
Post by: aa5wg on November 01, 2012, 01:21:11 PM
Vic:

I agree, any of these gauges would work.  Yes, the larger gauges are heavy.  Over the years I tried some heavier wire and it worked well at my station.  It seems I read an article talking about advantages of #10 for high power.

In the shed I have a pile of #10 and #8.  The #8 is VERY heavy but I have it.  I hate the idea of buying more wire at today prices.  Why not use the stuff I have laying around.  That is why I was asking about larger wire.

Chuck



Title: Re: Open Wire Spreader
Post by: W1AEX on November 01, 2012, 06:59:12 PM
How rigid are those Fi-Shock 4 inch insulators?  Do they flex or bend?  Dose Fi-Shock make a non-ribbed smooth version?

Chuck - I would describe the insulators as "stiff" but not rigid. If you pick one up you can flex it slightly but the ribs keep them straight. That being said, it's possible to bend one back onto itself with a little effort. With the same effort, you can then bend it back straight and it will re-assume it's straightness. The force required to bend them is far more than one of these would ever encounter in use as an open wire spreader. My feedline has been up in the air for close to 2 years and none of the spreaders show any signs of stress or deformation. I don't believe that Fi-Shock makes a non-ribbed version of the tubular insulators.

Vic - When my daughter-in-law first noticed the open wire line heading up into the sky she politely asked me, "What's the hamster ladder for?" I told her that there were lots of elderly squirrels in the woods and that it helped them to get up and down the trees. She giggled and hasn't asked any more questions about it but I can tell she thinks it's sporty too.

Rob W1AEX


Title: Re: Open Wire Spreader
Post by: aa5wg on November 01, 2012, 10:22:40 PM
Rob and all:

I went down to Tractor Supply and found the 4 inch ribbed tube insulators.  The salesman said Fi-Shock was sold to by Zareba.  I bought the last box of 200.  The box is now yellow and black with Zareba on it in stead of Fi-Shock.  The price was $12.99 plus sales tax.   

I see what you mean by being a bit pliable but fairly strong. 

When the cable ties show up from UPS I will give this a try.

Thank you.
Chuck


Title: Re: Open Wire Spreader
Post by: K1JJ on November 01, 2012, 10:34:53 PM
About 5 years ago I built 300' of 3/4" spaced open wire for 6M use.  It needed to be very low loss and close spaced to keep radiation to a minimum. It was intended to feed a fixed stack of 2el 6M Yagis.

To make the OWL, I bought about ten feet of white 1/4" Teflon rod. I cut it into 1" lengths and drilled holes in the ends. I slipped them thru #10 solid enameled wire. I used #16 wire to tie the teflon rods to the #10 openwire.

Worked like a charm on 6M.  Pretty lightweight too.  I shud take some pics of it and post here.

I finally ended up going with hardline and coax to feed the 6M Yagis, so have this FB openwire sitting around. Shud use it for something...

T


Title: Re: Open Wire Spreader
Post by: Detroit47 on November 02, 2012, 10:35:01 AM
I checked out the samples at Dayton. And I liked them so I bought a bag that was labeled for 100 feet. I haven't used them yet. I currently am using True Laddder line with no regrets. http://www.trueladderline.com/ So I don't know about using a diffrent wire size, Send them an Email and ask them.


Title: Re: Open Wire Spreader
Post by: ke7trp on November 02, 2012, 12:42:58 PM
16 AWG stranded wire is plenty for any BC rig on OWL line.  GOing larger is not going to do anything but increase weight.  It runs ICE cold

Lots of neat ideas. 

C


Title: Re: Open Wire Spreader
Post by: W2VW on November 02, 2012, 12:56:51 PM
16 AWG stranded wire is plenty for any BC rig on OWL line.  GOing larger is not going to do anything but increase weight.  It runs ICE cold

Lots of neat ideas. 

C

A number of us do not have room for a half wave doublet. Wire gauge can become an issue when feeding low radiation resistances.


Title: Re: Open Wire Spreader
Post by: ke7trp on November 02, 2012, 01:00:20 PM
Good point!

C


Title: Re: Open Wire Spreader
Post by: W4NEQ on November 02, 2012, 04:11:39 PM
Although we might be getting into the area of diminishing returns, larger gauge certainly has lower loss, particularly at low impedances or with high circulating currents - not uncommon when operating the line well off its Zo.  I use #10 with 2 inch ceramic spreaders for a line impedance of about 440 ohms.

This well known graph shows loss for #12:

http://w4neq.com/img/arrl_loss_graph.jpg



Chris



Title: Re: Open Wire Spreader
Post by: ke7trp on November 02, 2012, 07:58:29 PM
If the antenna is not very short for the frequency, there will be no gain in going over 16 awg. The current is low, There is no heating of the line.  I can see where going past that might help on a very short line on 160 or 80.

Thousands of people including me use the available 600 ohm open wire line and that uses 16AWG.

C


Title: Re: Open Wire Spreader
Post by: aa5wg on November 02, 2012, 09:07:24 PM
Tom and all:

Today UPS delivered a batch of cable ties.  I tried these cable ties with the Fi-Shock insulator, mentioned above, and I must admit it looks like a good spreader.  I'll have to try these in the winter to see how snow and ice work out.

There are other materials that are more rigid and smoother (round) than the Fi-Shock insulator.

However, for mechanical simplicity and investment the cable tie/Fi-Shock system may be top dog for home brew ladder line.

Chuck

 





Title: Re: Open Wire Spreader
Post by: W2PFY on November 02, 2012, 09:19:32 PM
I think this subject was up once before and I recall someone I think from Africa who may be a member here that was manufacturing spreaders at a very reasonable price. Anyone else out there remember who that might have been?

well I answered my own question. Here is the link

http://www.instantladderline.co.za/home.html (http://www.instantladderline.co.za/home.html)


Title: Re: Open Wire Spreader
Post by: aa5wg on November 03, 2012, 09:27:28 AM
These look good.  Do you know if the wire slips during high winds?

Chuck


Title: Re: Open Wire Spreader
Post by: W2PFY on November 03, 2012, 09:50:27 AM
These look good.  Do you know if the wire slips during high winds?

Chuck

Why not send him a email and ask and while your at it, find out what he wants for them in the USA?


Title: Re: Open Wire Spreader
Post by: W2NBC on November 03, 2012, 10:20:51 AM
https://www.youtube.com/watch?v=qzFKGB6qkXs&feature=youtube_gdata_player

Survived 97 mph winds here.. using # 12


Title: Re: Open Wire Spreader
Post by: VE7 Kilohertz on November 03, 2012, 10:47:25 AM
Hi guys,

I am about to re-erect my 80M double Ex. Zepp with a new steel end support mast, which I'll post some questions about in a separate thread, but I also want to replace my old Johnson porcelain spreader feed line with new lighter weight spreaders. I am using #14 solid and the Johnson 104 ceramic spreaders and have about 60' of feed line.

Could someone post a closeup pic of the Fi-shock insulator or a part #? I found 6 pages of various insulators on their website, but don't see anything suitable.

Thanks,
Paul
VE7KHz


Title: Re: Open Wire Spreader
Post by: aa5wg on November 03, 2012, 12:21:00 PM
Paul:

I was told that Fi-Shock was bought by Zareba.  Their insulator part number, by Zareba, is HT4FT1200.

Here is a link showing a new picture of the box that contains 200 of the 4 inch insulators.

http://www.hk94.com/B0079GH998.shtml

In Traverse City, Michigan this new Zareba box for 200 insulators was $12.99 plus tax.

W1AEX has a nice web page that shows this same 4 inch insulator.  The blue box on his site is the old       FI-SHOCK box that holds 200 of these insulators.

Here is his link:

http://www.w1aex.com/owl/owl.html

Chuck


Title: Re: Open Wire Spreader
Post by: VE7 Kilohertz on November 03, 2012, 12:33:44 PM
Thanks Chuck.

Now I see what they look like. Lots of farm supply places around here so I should be able to find something today.

73

Paul


Title: Re: Open Wire Spreader
Post by: aa5wg on November 03, 2012, 09:37:06 PM
Hi Paul:

Your welcome.

Chuck


Title: Re: Open Wire Spreader
Post by: VE7 Kilohertz on November 10, 2012, 12:33:11 PM
I've decide to go down a different path. N4LQ posted a Youtube video a while back, which I found in my search for spreaders. He used a cheap pen tube, and zap straps to hold the wires, brilliant idea, but I wanted something a little more robust, and free.  ;D I remembered I had 100's of feet of PEX given to me years ago, in various sizes. I found a coil of white 1/4" and made up this sample. I had a bag of 7.5" UV rated ties. It's amazing how much lighter this is over the ceramic Johnson bars. I am updating my wire as well. It was #16 and I found I had 1000's of feet of new on the spool #14 heavy enameled from my wind turbine prototyping days. So my new feedline will consist of the #14 enameled wire with these 1/4 diameter tube spreaders and the black zap straps. The tube has very little room for any critters to get in. It's pretty tight. Wire spacing will be 3", which is identical to the Johnson spacers. The 7.5" zap straps are JUST long enough. Impedance will be about 540 ohms.

Here are a few pictures of the sample I made up.

Cheers

Paul
VE7KHz


Title: Re: Open Wire Spreader
Post by: wb2jix on November 10, 2012, 01:17:26 PM
http://www.trueladderline.com/ladder/ladder.html (http://www.trueladderline.com/ladder/ladder.html)

Mine has been up for 10 years. No worries. I build a counterweight/pulley arrangement for when the wind blows.
He might sell you just the spreaders or make your own. They are so simple and foolproof. I am happy to take macro closeup photos if you need any. I remember looking at his antennas and saying to myself "heck; I can do that for a lot cheaper!" Good luck. Spend the money; support a guy that is super helpful and get it up in the air.

Brian



Title: Re: Open Wire Spreader
Post by: ke7trp on November 10, 2012, 04:59:39 PM
Out here in AZ the Zip ties wont work.  They end up snapping off in a year. Very brittle.. The heat and sun just take them out.

I have the line that brian just posted.  Its been up for a few years. No trouble. No problem in the wet or in high winds. Using it right now on 40 meters.

C
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