| Author |
Message |
    
Killer
Junior Member
Username: Killer
Post Number: 13
Registered: 1-2007
| | Posted on Wednesday, April 25, 2007 - 6:57 pm: | 
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Can someone point me in the right direction for a chart or something to tell how far apart my guy wires need to be.My tower will be 65 feet tall from the hinge plate to the nipple.I need to know how many sets of wires,how far apart they will be on the tower and how far they need to be away from the base of the tower.Around a year ago i found a chart on Rohn towers that gave all the info i needed but know i cant seam to find it on the internet anywhere.
Not sure if it matters but my tower is a little different than most I've seen.Not sure who made it but its a different size than any of the Rohn 25 towers I've put up.Its 15 1/2" wide where the Rohn 25 was 12" wide.Also the tubing wall is thicker and the Z braces are bigger in diameter.All this makes for a stronger but heaver section vs a Rohn 25 section.Not really sure how this would affect the guy wires.Less because it stronger?More because it heaver?Or the same amount? |
Tech833
Moderator
Username: Tech833
Post Number: 1673
Registered: 8-2002
| | Posted on Thursday, April 26, 2007 - 1:39 am: |
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It goes by scope. The higher the winds or antenna windload, the broader (lower) the scope needed. a 40 degree scope is a normal minimum for most installations. You can go 45 or up to about 60 degrees from vertical without a lot of extra vertical loading. Anything over 60 causes a lot of unnecessary tower load. |
Wildrat
Senior Member
Username: Wildrat
Post Number: 1279
Registered: 12-2003
| | Posted on Friday, April 27, 2007 - 11:40 am: |
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You may want to consider Kevlar rope also. I use it on mine mainly because the salt eats the cables up in no time. The rope is stronger than the wire, and is also UV safe. I have always did my guy wires/ropes by sight. I did read about guying years ago and I do remember getting the tape and calculator out. The problem is most times you can't get the ideal setup at home due to the house, pool, boat, garden, trees, wife. Anything is better than nothing. I need more on mine, but I will have to lay the tower down to put more ropes on. The other thing is to remember when it's laying on the ground it does not look as tall as it does when standing.
WILDRAT
Mark
27.285MHZ
CEF674
CVC029
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Bullseye
Intermediate Member
Username: Bullseye
Post Number: 315
Registered: 1-2002
| | Posted on Friday, April 27, 2007 - 4:13 pm: |
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The general rule of thumb I've always heard is the guy anchors should be 60% of the total tower heighth away from the base of the tower but in reality,like Wildrat pointed out,is thats not always feasible but I would try to get as close as possible to that measurement. As for where to put them I'd go at 30 and 60 ft. you can use one set anchors for both sets of guys because the set at 30 ft. is mainly to keep the tower from flexing in the middle. Steel wire will work but ,again agreeing with Wildrat, synthetics like kevlar or Phillystrand last longer and are stronger.
Bullseye/CEF#110/Mem. Since 1/18/2002
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Killer
Junior Member
Username: Killer
Post Number: 14
Registered: 1-2007
| | Posted on Friday, April 27, 2007 - 5:59 pm: |
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Thanks for the help.I'll be using steel cable since i already have it.Got lucky and got it free. :-) |
Tech237
Moderator
Username: Tech237
Post Number: 751
Registered: 4-2004
| | Posted on Saturday, April 28, 2007 - 8:39 am: |
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Killer,
Do something really sneaky. INsulate the wires from the tower about 3 inches from the top and again at 9feet down and have yourself a switchable dipole array as well.
Simon
Tech237
KD7IEB
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Killer
Junior Member
Username: Killer
Post Number: 15
Registered: 1-2007
| | Posted on Sunday, April 29, 2007 - 6:15 pm: |
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Funny you should mention that.I just help take down a 100 foot tower today and the guy had ceramic insulators near the top and middle of all the guy wires.He no longer lives there to ask.I wounder if he had done something like that. |
Tech237
Moderator
Username: Tech237
Post Number: 758
Registered: 4-2004
| | Posted on Monday, April 30, 2007 - 9:03 am: |
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Most likely he had just broken the guys into non-resonant lengths as is recommended, but you never know.
Simon
Tech237
KD7IEB
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Tech833
Moderator
Username: Tech833
Post Number: 1674
Registered: 8-2002
| | Posted on Monday, April 30, 2007 - 11:12 am: |
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If the tower had a horizontal polarized beam on it, the guy wire insulators were probably to help keep them from distorting the pattern. At 27 MHz., not too big of a deal, but on the lower ham bands, it is a big deal. |
Killer
Junior Member
Username: Killer
Post Number: 16
Registered: 1-2007
| | Posted on Monday, April 30, 2007 - 6:38 pm: |
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Yeah the guy was defiantly a ham operator.The tower had 4 antennas on it and another one stuck in the ground about 60 foot from the tower.He had a Maco 4 element horizontal on the top at 100 feet,a scanner antenna mounted at 80 feet,a Antron 99 sticking off the side at mounted to a brace at 40 feet.And on the other side of the tower at 40 feet he had some kind of smaller 7 element beam mounted to a brace sticking off the side.And i don't have a clue what the antenna mounted in the yard was for but it was made of aluminum and tall with 2 small radial kits on it with a stinger sticking out the top. |
