Tail pieces 'pigtails' of EHS at the groud end of the Philly are highly recommended. The total cost difference was not significant in my small tower installation (70' Rohn 25) so I went with the Phillystran. I just didn't have the time to do all the measuring, cutting, and assembly and get the tower up before contest season. In my case, I compared the total cost of the Philly to the EHS with insulators, clamps, thimbles, and estimated my time in assembling all of that. (The cost of your installation in Phillystran must be compared to the total cost in the EHS installation, not only in hardware, but in your time as well. I am thinking in terms of tool buckets, climbing belts and the like bouncing off Philly as a potential source of problem, if you bump into EHS who cares! Phillystran can be terminated with a special preformed grip made by Preformed Products.Īlthough it entails two more guy ends and hence, ups the cost per guy, it seems like the EHS pigtail at both ends of a Phillystrand guy is a nice inexpensive comfort margin. It is a commercial product and its PVC jacket gives abrasion and UV resistance so that its service life is probably 20 years or longer. You need to use factory pre-formed guy grips for the bigger sizes but for boom trusses using the smallest size, cable clamps are okay. After 23 years in this worst case scenario, it still retains 75% of its rated tensile strength.īottom line? It'll last a long time and is a worthwhile investment particularly if you're planning on having a populated tower/antenna system and want to minimize any potential interaction problems. In places the jacket has disappeared and the core is out in the Florida sun. Some of the oldest Phillystran (with the old jacket material) is still being used in southern Florida. may have an impact on how long it retains its characteristics. The service life may also be related to the region and environment the more UV, heat, wind, etc. No one knows how long it'll last past that because it hasn't been around long enough. Phillystran has only been manufactured since 1974 so thus far the longest service life of the product has been 23 years. The purpose of the jacket is: 1) protect the cable from abrasion during installation, 2) prevent moisture from wicking into the core and 3) most importantly, protect the core from UV damage. Phillystran consists of a Kevlar fiber core and a PVC jacket. It appears Texas Towers may be the only Phillystran supplier in the ham market. It comes in different diameters and strengths. Phillystran is a non-conducting guy wire material made out of aramid fiber and is like Kevlar - strong and lightweight. 3/16 EHS is rated at 3990 pound strength. Yes, the whole process is tedious but just think how well you'll sleep nights knowing you did everything correctly.ġ/4" EHS guy cable is rated at 6700#. Check with your local suppliers there are also thimbles that are U-shaped with enough clearance in the mouth that you should have a minimum of fuss installing them. Many are teardrop-shaped these are the ones that you'll have to open up when installing them. Moving along, you'll need to use thimbles when using the guy assemblies but they are smaller diameter than the legs and you shouldn't have as much trouble getting the thimbles over them. Since 25G is 1.25 inch OD, it does give an acceptable seat diameter for installing the preform grip directly on the leg. BTW, the 'seat diameter' (which is the distance/radius required) for a 3/16" preform is one inch minimum. 3/16" preform grip takes a 7/16 to 3/8 inch thimble. There is a specified size of thimble for each part of the guy wire system i.e. This is the function of the guy assemblies to add torque resistance. Although the tower leg gives you a nice convenient radius for the preforms, this technique does nothing for the wind induced torque that will try to twist your tower down. Old type cable clamps are cheaper but tend to loosen with age as the joint forms itself to the cable after tightening. Preforms, or ?dead ends? are the most reliable and easiest way to terminate the guys. The following was gathered from posts to the TowerTalk mail reflector by Mark K1LOģ/16" type EHS galvanized wire works well.
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