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Discussion Starter · #1 ·
When the warning says not to put up the antenna too close to where the power line comes into the house whydo they say that?


Is it because if the antenna is too close the installers can be electrocuted or is it that the mfg are afraid that the installers might drop the antenna & then can get electrocuted? If it is the latter then it's just a matter of being careful, correct?


I know, a rather dumb question :confused:


Robert
 

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All of the above, plus....


You don't want it where it can fall onto a power line (or, a power line fall on it) while it is connected to your expensive equipment. And, of course, not while your fingers are touching that equipment, either!


The funny part is, it needs to be grounded to the same point as the incoming power drop, so it still needs to be close.
 

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The basic answer is yes it can have an effect. It really depends on what is running in the wires. If it is the normal high tension lines running into a pole pig then the effects are minimal. The main effect is actually from the wires themselves causing a disturbance in the uniform field around your antenna. If you are above the wires it is no problem. If you are looking through the wires, it can have an effect.


Very high tension lines like those around substations have high fields and are prone to causing much more interference.

For most applications, you want your antenna high enough that it is not affected by powerlines, buildings trees etc. Installing antennas most always involves some amount of compromise. For TV type signals, the field strengths are high enough that if you do what your neighbors do you are usually in pretty good shape.


..Doyle
 

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DoyleS,

I will have to disagree with most of what you stated. There is NO effect on reception from the electromagnetic radiation from power lines on antennas and properly designed electronics. The only way they would interfere with equipment operating in the VHF and UHF is from noise caused by leaky insulators, bad connects, bad transformers. Most of this interference is the commonly heard static on the AM radio. Most of the noise is caused by sparking and is the form of pulse noise which can reach up to the VHF and UHF realm.
 

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patjoy,


If that was the case, then FM radios would perform faultlessly when you passed under high tension lines and they do not. There is both a shielding effect and an overload effect that couples into the signal lines. High tension insulators are constantly having to be cleaned to eliminate the arcing you describe. The field itself causes much of the buildup. Once that arcing are discharging of any kind takes place, that current flow to supply the arc travels in the wires and causes a tremendous amount of interference that disturbs AM, FM and other signals. The normal lines running into the pole pigs are 12KV lines and these are not the ones that cause the problems. The problems come from the larger lines which are typically on towers. When one talks about interference in the electromagnetic spectrum, you have to include more than 60Hz since there is much more than 60 hz on those lines. The question asked was pretty general and maybe I took off on a different tack from what was asked. Most people do not want antennas near power lines, metal buildings or other objects that can cause signal problems.


..Doyle
 
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