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Author Topic: Making old buzzard ladder line?  (Read 3744 times)
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K1ZJH
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« on: July 04, 2010, 09:01:18 AM »

I'd like to use some 14 gauge thnn electrical wire I have on hand for my ladder line, along with 6" ceramic WL spacers.  Problem is fixing the ceramic insulators to the insulated 14 gauge stranded wire?

I was thinking of using some black UV resistant tyraps as temporary locks, and then applying a liberal amount of silicone caulking over the tyraps and into the wire pass through hole in each end of the spacers.  Is there a better way to do this?  I have the spacers and wire, and would like to use them. Grin

Pete
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« Reply #1 on: July 04, 2010, 09:31:50 AM »

The old ceramic spreaders were originally designed to be attached to the feeders with short pieces of small gauge wire. Pass the small wire thru each hole in the end of the speader and then wrap each end around the feeder wire.  I have done this and constructed open wire with THHN feeders and it works fine.  The ty wraps might also work fine, if you can pull them tight enough to keep the spreaders from slipping up and down on the feeders.  I have also used 6" lengths of small PVC pipe/tubing for spreaders as well as plastic hair curlers  Shocked and lengths of fiberglass rod that are sold for driveway markers.  

I just ordered some of those snap on plastic spreaders mentioned in another thread.  They are designed to be used on #14 THHN and look really great....we will see.  They aren't cheap, but might work out nicely for a neat installation.
  
http://www.dtsohio.com/73cnc/laddersnap.html

The problem with the ceramic spreaders is weight.  They are pretty heavy and a long length of transmission line will weight down the antenna a bit.

73,  Jack, W9GT
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« Reply #2 on: July 04, 2010, 01:22:00 PM »

The old ceramic spreaders were originally designed to be attached to the feeders with short pieces of small gauge wire. Pass the small wire thru each hole in the end of the speader and then wrap each end around the feeder wire.  I have done this and constructed open wire with THHN feeders and it works fine.

The problem with the ceramic spreaders is weight.

73,  Jack, W9GT

Jack is correct about the ceramic spreaders.  The feeder wire rests in the groove at the end and is held in place with short lenghts of wire which is first put through the hole and then wrapped around the feeder on each side of the groove.  Two or three turns should work fine.

I have hundreds of foot long ceramic spreaders.  Probably end up with an impedance of about 1000 or more ohms (haven't really calculated it yet).  The only reason I have not yet made up the feeder line is I still don't have the crane one would need to get the feeders and antenna off the ground Grin

Fred, KA2DZT
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k4kyv
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Don
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« Reply #3 on: July 04, 2010, 02:43:41 PM »

Just make sure the wire used to tie the feeders to the insulator is made of the same metal as that of the feeders.  I made the mistake years ago of using steel wire, which was apparently zinc or otherwise plated.  The line worked fine, until after the first rain.  Then I wiped out every TV within a quarter-mile radius.  Turns out that the plating on the wire had migrated onto the main feeders and corroded with the  rain, and every tie point became a diode rectifier.  I took down the line and replaced the steel wire with copper, and the problem went away and never returned.

I have used 18 gauge copperweld (the real stuff, not copper plated electric fence wire) without a problem.  But some copperweld might be too springy, and impossible to make a tight wrap because it springs back a little and loosens up after you make the wrap.  Plain old copper magnet wire would probably be the best choice.
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Don, K4KYV                                       AMI#5
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Steve - WB3HUZ
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« Reply #4 on: July 04, 2010, 02:57:14 PM »

That should work. I used epoxy for some line I made years ago. Worked FB.


I'd like to use some 14 gauge thnn electrical wire I have on hand for my ladder line, along with 6" ceramic WL spacers.  Problem is fixing the ceramic insulators to the insulated 14 gauge stranded wire?

I was thinking of using some black UV resistant tyraps as temporary locks, and then applying a liberal amount of silicone caulking over the tyraps and into the wire pass through hole in each end of the spacers.  Is there a better way to do this?  I have the spacers and wire, and would like to use them. Grin

Pete
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« Reply #5 on: July 04, 2010, 10:42:27 PM »

Hot glue gun? 

But let's do some thinking about the weight thing.  It being summer it's easy to overlook a few things.  the ceramic spreader line is going to be heavy as it is, but think about it with some ice on it and a 30 mph wind.   I'd use it on the ground between ground supports but for the drop from the dipole feedpoint down to ground level I'd use some other lighter weight spreader, especially if the feedpoint isn't supported by anything. 
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K1ZJH
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« Reply #6 on: July 05, 2010, 06:32:05 AM »

With six inches between the conductors, I was figuring on a sparcity of spacers, maybe one every 7 feet to keep the weight down? Or will that be a problem?

Those plastic clip on spacers also look interesting.
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« Reply #7 on: July 05, 2010, 12:11:29 PM »

I think that might be a problem. I have found that my open-wire feedline gets tossed around quite a bit when the wind comes up. At times it will flip over on itself and twist. If there are not enough spacers present, you could end up with a shorted feedline if this happens, and it will tack weld itself very nicely when power is applied. I ended up with spacers every 12 inches to prevent this. Probably overkill, but it has not failed yet, even with extreme weather and wind.


* feedline.jpg (4.86 KB, 159x300 - viewed 199 times.)
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k4kyv
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« Reply #8 on: July 05, 2010, 12:59:41 PM »

I think that might be a problem. I have found that my open-wire feedline gets tossed around quite a bit when the wind comes up. At times it will flip over on itself and twist. If there are not enough spacers present, you could end up with a shorted feedline if this happens, and it will tack weld itself very nicely when power is applied. I ended up with spacers every 12 inches to prevent this. Probably overkill, but it has not failed yet, even with extreme weather and wind.

The best solution, if practicable is to have the antenna attached to a rigid structure like a pole or tower, right at the feed point.  Then you can put tension on the line and reduce the number of insulators because the stretched wire will not flop about.  Mine is almost 120' long, with 2-inch spacing, and I  have one spreader every 10 feet.

One word of caution, though.  Don't stretch the line too near its breaking limit during warm weather.  The length of the wire contracts with cold temperatures.  I had mine too tight (adjusted the turnbuckles in mid-summer), and during a severe cold snap, one of the insulators pulled apart.  Fortunately, it was one at the bottom end, not the top, so I didn't have to climb the tower in mid-winter to replace it. The broken insulator was a dog-bone ceramic type, and my "temporary" repair, made about 8 years ago, was with a scrap piece of Phyllistran.  I just wrapped 2 or 3 turns through the loop left in the wire, and back up through the bottom anchor, and fixed the whole thing in place with a piece of black plastic tie-wrap.  One of these days I'll fix it with a real insulator, but so far my JS has worked as well as the insulator did before it broke.  See photo below.

I have used open wire suspended from the middle of a wire dipole strung between trees. I once used standard 6" EF Johnson ceramic spreaders, but as the wire tossed about in the wind, spreaders would break. I replaced them with homebrew ones made of 1/2" solid plexiglass rods, and never had the problem again, plus the plastic rods were lighter in weight.






* 100_0964.JPG (1151.52 KB, 2576x1716 - viewed 234 times.)
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Don, K4KYV                                       AMI#5
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Ed/KB1HYS
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« Reply #9 on: July 05, 2010, 05:03:03 PM »

You can also guy the feed line to prevent whipping about in winds and such.  I've put spacers eer 18-24 inches  with no problems.   

I'll be making another batch to replace the 300ohm twin lead currently in use, so I can go QRO.
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73 de Ed/KB1HYS
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 "I've spent three quarters of my life trying to figure out how to do a $50 job for $.50, the rest I spent trying to come up with the $0.50" - D. Gingery
WA1GFZ
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« Reply #10 on: July 05, 2010, 06:44:59 PM »

I use about 10 inches of #14 as a support wire on my #10 feeders spaced 4 inches. They are spaced every 30 inches. You want about 5 wraps on each side to keep the spreader from sliding on the feeders. Don't make it too tight or the ceramic will crack. My 1983 feeders are showing their age but still work fine.
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KB2WIG
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« Reply #11 on: July 05, 2010, 07:14:49 PM »

 How does one wrap the insulated wire to secure the ceramic spacers? Wrapping bare wire across the conductor, through the hole and wrapping the other side to secure a bare conductor to the end of the spacer  - this  I understand.  Doya use uv resistant wire ties, 4 per spacer to secure a spacer; bare #14 to secure the insulated wire, hot glue, carona dope??  I can see a problem with insulation compression by bare wire allowing the spacers to become loose or to intermittently rub the conductor the wrong way.

klc
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Ed/KB1HYS
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« Reply #12 on: July 05, 2010, 08:41:26 PM »

with insulated wire, I doubt it much matters as long as you don't damage the insulation.  I used 1/4 inch fiberglass rods (driveway markers) and 14 gauge THHN wire and wrapped a 2 inch piece of galvanzed steel wire (like fence wire) about the ends of the spacers to hold.  Worked FB.   Lasted until a branch took out the dipole it was on which tore up the whole she-bang.
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73 de Ed/KB1HYS
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 "I've spent three quarters of my life trying to figure out how to do a $50 job for $.50, the rest I spent trying to come up with the $0.50" - D. Gingery
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« Reply #13 on: July 06, 2010, 11:13:49 AM »

I built my open wire line about 30 years ago and to this day it has never failed.  Its about 125' long and feeds the center of my 160M Inverted Vee.  For spreaders I used 3/8" Lexan clear rod stock.  I cut the spreader to be approximately 5.5" long.  I used a band saw to cut to slits on each end.  Then in from the slit I drilled a small hole.  The feeder wire rides in the slit and its held in place with a short small gauge wire which goes through the small hole and then wraps around the feeder wire.  This is the same concept as the old fashon spreaders.  I have a spreader ever 12".  My feeder wire is 14 Ga magnet wire and the short wrapping wire is maybe 20 Ga or so.  Its not heavy at all and has worked flawless for at least 30 years. 
Regards,
Joe, W3GMS         
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« Reply #14 on: July 06, 2010, 07:05:10 PM »



That "superhet66" guy - KC2YOI put the ladder line in the pix below together and I snapped the shot!

I'm not sure but it might be a training thing for squirrel olympics, not sure...   Roll Eyes


* YOI-Ladder.jpg (284.51 KB, 768x1024 - viewed 208 times.)
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Ed/KB1HYS
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« Reply #15 on: July 07, 2010, 09:14:27 AM »

The best solution, if practicable is to have the antenna attached to a rigid structure like a pole or tower, right at the feed point.  Then you can put tension on the line and reduce the number of insulators because the stretched wire will not flop about.  Mine is almost 120' long, with 2-inch spacing, and I  have one spreader every 10 feet.

One word of caution, though.  Don't stretch the line too near its breaking limit during warm weather.  The length of the wire contracts with cold temperatures.  I had mine too tight (adjusted the turnbuckles in mid-summer), and during a severe cold snap, one of the insulators pulled apart.  Fortunately, it was one at the bottom end, not the top, so I didn't have to climb the tower in mid-winter to replace it. The broken insulator was a dog-bone ceramic type, and my "temporary" repair, made about 8 years ago, was with a scrap piece of Phyllistran.  I just wrapped 2 or 3 turns through the loop left in the wire, and back up through the bottom anchor, and fixed the whole thing in place with a piece of black plastic tie-wrap.  One of these days I'll fix it with a real insulator, but so far my JS has worked as well as the insulator did before it broke.  See photo below.
<SNIP>


Also springs can be used to tension the feedline at the end points.  leave a loop and tension the spring at about 25% draw on the hottest days.  IIRC but I think I've seen this on some photos of older installations that did this.  Between guys and tension the feedline should be very stable.
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73 de Ed/KB1HYS
Happiness is Hot Tubes, Cold 807's, and warm room filling AM Sound.
 "I've spent three quarters of my life trying to figure out how to do a $50 job for $.50, the rest I spent trying to come up with the $0.50" - D. Gingery
WA1GFZ
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« Reply #16 on: July 09, 2010, 07:52:46 PM »

I also use all magnet wire. insulated is very heavy and doesn't serve any purpose.
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K1ZJH
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« Reply #17 on: November 17, 2011, 02:58:56 PM »

I ended ordering the LadderSnaps mentioned in another thread.

I used them with 14 gauge electricians THHN wire as suggested by
the manufacturer.

The antenna and feedline withstood the Nor'easter in October, despite the
antenna and line taking a few hits from falling branches. The electrical plastic
conduit supporting the line away from the shed was destroyed, but the
spreaders held their grip.

http://www.73cnc.com/


Pete
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k4kyv
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« Reply #18 on: November 17, 2011, 03:52:05 PM »

A week or so ago I threw together about a dozen feet of open wire line to run between my prototype tuners and the big 450-ohm dummy load, using the small 2" EF Johnson ceramic spreaders.  Normally for OWL I use bare solid wire, but all I had on hand was some insulated #12 stranded single-conductor.  I used that, and tied on the insulators with short pieces of #14 bare solid.  I found some scrap 14-2 w/g Romex and stripped off the insulation to use the #14 conductors for tie wire.

I attached  the spreaders the conventional way, laying the conductors in the grooves at the ends of the spreaders, running  the tie wires through the holes, and wrapping a few turns of tie wire at each end over the  conductors.  With bare wire, the insulators tend to slide up and  down the conductors unless the tie wires are wound very tightly and maybe even crimped with pliers. OTOH, I found that with plastic-insulated wire, even when the tie wires are wound loosely, it is practically impossible to move the insulator up or down the conductor without loosening the tie wire to the point that it is almost unwrapped.  I had to do that a few times when a spreader would end up cocked at an angle and one end had to be re-positioned.

I'd consider that another reason why insulated conductors might be advantageous for fabricating OWL.
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Don, K4KYV                                       AMI#5
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« Reply #19 on: November 17, 2011, 04:42:13 PM »

The storm took down my 160 meter ant. My 1983 #10 with #14 tie wires required me to replace 1 broken spreader and 3 #14 tie wires. I use about 7 inch #14 tie wire on johnson 4 inch spreaders spaced 30 inches. It is starting to show its age but only on the conductor surfaces. Insulated owl is quite heavy I like bare solid conductors.
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« Reply #20 on: November 17, 2011, 09:57:39 PM »

Ed has a good idea, use a spring at the end of the line.  I have used garage door opener springs.   These are heavy duty springs that help open your garage door in you home.  Garage door installers throw these away or you may buy new at the hardware store.  They have good stretch and contraction for this application.  Don't use the ceramic insulators.  Instead use a source of hollow plastic tubing, i.e. grey PVC, ink pens, etc.  

Look at this YouTube clip and see how to use wire ties.  This seems to be a good way to go.  Ceramic insulators require two small (i.e 3 inch length or so) wires to secure each side of the line to the insulator.  Like Don said if the two wires (line and tie wire) are not of the same kind of metal then there is going to be RFI trouble.  Even if they are of the same type of metal there is still a possibility of trouble.

If you have time you may search for UV resistant engineering plastics.

 http://www.youtube.com/watch?v=qzFKGB6qkXs

Chuck
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« Reply #21 on: November 18, 2011, 06:44:18 AM »

The YouTube link is about the simplest and very strong.

I bought the "True Ladder Line" product and he uses PVC that has slits on each end. The wire barely fits in the slit and I have never had any trouble of flipping or breaking in the worst of Western Pa. WX.,,,,,going into the third year.
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WA1GFZ
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« Reply #22 on: November 18, 2011, 10:53:02 AM »

I'm at 28 years
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« Reply #23 on: November 18, 2011, 11:44:28 AM »

If someone is making "Old Buzzard" ladder line, they should consider real old time spacers.  Wooden dowel rod boiled in wax.  On the advice of an old ham I made up a feedline with wood spacers about 25 years ago.  The dowels came from the hardware store, were cut into 6 inch lengths and I drilled holes near each end for the tie wires.  The wax was toilet drain seals heated outside the house in a pot on a hot plate.  The boiling wax is super flammable so be careful. 

No problems in all these years of use.

Charlie
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« Reply #24 on: November 18, 2011, 12:57:55 PM »

This is a question more than a reply:

When designing my own parallel-line feedlines, I've avoided using tie wires at the ends of spacers.  I've worried that all the extra little sharp edges, corners, and points, of those tie wires, allow high voltage-gradients at the sharp edges and corners, and thus increase the likelihood of received noise.

Isn't that why there's generally a li'l round ball at the end of a whip antenna?

If my thinking is incorrect, please let me know.

-al hart, w8vr

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