Installing Antennas in Software

Paint PDF417 in Software Installing Antennas

most communications sites will render cheap radios unusable) to coordinate efforts beyond shouting distance Last but not least what goes up must come down and eventually does The following picture (Figure 164) is the aftermath of a fallen tower, one I have climbed and worked on (No, the damage is not my fault) Standing about 15 years or more, this tower gave in to 60+ MPH winds during a late winter storm in Northern California This tower looked and was safe for the most part and was not suspected of suffering damage in the winds it is normally exposed to

Figure 164 High winds broke this communications tower in half The structure at the right is a temporary tower erected to maintain communications until repairs to or replacement of the existing tower could be done

Aside from age or rust, the contributing factor to the demise of such towers, normally able to withstand 120 MPH or higher winds for short periods of time, is the amount of stuff mounted above critical structural points The tower itself presents a wind load factor that means stress applied laterally to the structure by wind pushing on brackets, pipes, cross-braces, etc Anything added to a tower presents more wind load Most cylindrical and exposed dipole antennas

16

add relatively little wind load by themselves, but several of them begin to add up Panel antennas and dishes add 2 to 10 times the amount of wind load of other conventional antennas Tower site owners and installers must be very careful to balance wind load factors versus antenna placement Of course everyone wants their antenna at the top of the tower, but that may not be safe, prudent, or reasonable, due to wind load or physical mounting issues Common sense must rule in the absence of anything else Look around Listen carefully Be aware Pay attention Think about every action and potential reaction If something looks, feels, or sounds like it might break loose and fall, it probably will Stay away from trouble spots and be safe!

The number two concern about antennas is doing it right Why bother if it is not going to work and last longer than a day, a week, or a month A good friend provided an excellent motto for this and other projects: The price of quality only hurts once Potato chip can antennas do not survive in the rain and winds Anything left outdoors for any period of time is going to be vulnerable to and suffer from the elements wind, rain, dust, sunlight, salty air, perhaps even snow and ice Few of us can afford the money to replace and the time to reinstall damaged antennas or feedline Face it, an antenna is not like your keyboard, mouse, monitor, computer, or router Once an antenna is installed, it is often forgotten as it should be, if you used the right materials and installed it all properly Select the best material you can find for the job at hand, and for as long as you expect it to last In some cases, select even better materials to give yourself a margin of safety and longevity Think about what an antenna system is and what it must endure throughout its expected lifetime An antenna system is made up of several pieces of hardware bits of metal, plastic, cable, nuts, bolts, cable ties, tape, and connectors Most of these pieces are left outdoors to the whim of the elements The hardware itself is not considered visually appealing or suitable to most people Any visual appeal or tolerance diminishes quickly

because of the elements, as may the performance, strength, or safety of what you have installed Corrosion and wind are your antenna system s two worst enemies Corrosion plus wind makes for an unsafe system