[TowerTalk] Poor man's guy wire tension guage

[Chris Wendling]

Here's another way to measure the tension in you guy wires, and all you  need is a small tape recorder and 3 ft piece of 2 by 4 lumber.
  
  Cut two small blocks off the ends of the 2x4, and nail them to the ends  of the long piece, on the side.  File or saw a "v" notch in the  small blocks, along the long axis, so the guy wires can sit in the  notches. This forms two bridges, so that when the 2x4 is placed agains  the guy wire, it can be "plucked" to produce a vibration.
  
  If you are erecting a Rohn 25 tower, the guys should be set to 400 lbs tension (+- 50 lbs).
  
  Now you need to "calibrate the instrument".  Take a piece of the  same guy wire, hang it from any tree, tower, frame, swingset, anthing  you can find overhead that can support about 300 lbs.  Form a loop  in the guy to put your foot in.
  If you step in the loop and hang you will tension the guy to your  weight. (say about 200 lbs).  While under tension, perhaps from a  friend, place the 2x4 against the wire, and pluck it like a guitar  string.  Record the tone on you tape recorder several times. Hint:  placing the recorder directly on the 2x4 helps capture the tone.
  
  Now, while you tension you tower guys wires, place the 2x4 against the  guys, and pluck them in the same way, listening to the tape recorded  tone. When the tension is the same as your weight, the tones will be  equal. For the CW guys, this is an easy thing to "zero" beat the tone.
  
  If you want to double the tension to twice you weight (say to 400 lbs),  the tone will have to be twice the frequency. There are several ways to  do this. One is to make another bridge from a notched block of wood,  and place it at 1/2 of the original separation distance. Another (if  you have a sound card and microphone) is to use your computer or other  ham test equipment to measure the frequency, and the produce one with  twice that frequency with a tone generator (many are free for the  download). Record that frequency on your tape recorder, and use it in  the field for the 400 lb "note"
  
  So for the cost of a 2x4, and a bit of time, you CAN "measure" the tension in your tower's guy wires!
  
  Chris-AI4MI