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Do radio transmitters have the capability of electrocuting copper thieves?

I found that question while perusing my search engine statistics today.  The short answer in theory is yes.  If you are a copper thief, it will most likely look like this:

That being the case, however, it is much more likely that an RF burn will result if one comes in contact with an energized antenna or transmission line.  Even small RF burns are painful, large ones can be nasty things.  RF burns occur because of the skin effect, that is to say, the higher the frequency of the AC waveform, the closer to the surface of any given conductor the current will flow.  It is the reason why five watt STL transmitters on 950 MHz use 7/8 or 1 5/8 inch cable to reduce losses.

When a human body part comes in contact with an energized RF antenna, the body part becomes part of the circuit, thus it follows the same principals.  The extremity that is making contact will have its skin burned off.  It also smells bad.

Getting an RF burn is a painful lesson on what not to come in contact with around a transmitter site.  But, that is not all.  Simply being in close proximity to radiating elements of antennas will induce body tissue heating, just like a microwave oven.  This can lead to all sorts of short term and long term damage to organs and other problems.

Therefore, the best thing is to avoid radio and cellular towers if you do not know what you are doing.   Stay out of fenced in areas around tower bases.  No matter how tempting that copper may look, you could be seriously injured or killed if you cut the wrong thing.

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3 comments to Do radio transmitters have the capability of electrocuting copper thieves?

  • Dewey Jacks

    I don’t even want to try it,but I am thinking if I were to touch the 450 ohm ladder line coming into my house from my G5RV antenna and hit the transmit(PTT)button on my Yaesu FT-950 putting out 100 watts barefoot,I could still likely suffer an RF burn,maybe?I can imagine how bad it would be coming close to a radio tower with a transmitter putting out 50K watts,…that would be enough to kill someone,if not give them a really serious RF burn!

  • Paul Thurst

    Dewey, It all depends on the antenna impedance at the frequency you are using. If the antenna impedance is low, the RF will take the path of least resistance, e.g. the antenna. If it is high, you will become an unintentional radiator. Dry skin resistance is about 300 ohms, to give you an idea of current flow: I = square root of P/R, thus 100 watt/300 ohms = 0.33333. sqrt of .3333 = 0.577 amps, which you would feel, although that might not be enough to create a burn. That would be the worst case scenario, e.g. all the current flowing through you versus the antenna. Chance are that only some of that would flow through you, thus the current would be less. I can tell you from experience, even 60 mA will cause some pain, and you probably do not want to do any experimentation with this.

  • Dewey Jacks

    Oh wow! In any case,keep in mind that if I came in contact with it by accident,…not on purpose,…I was just wondering what kind of an effect it would have. I should have mentioned if I had touched it by accident,and after reading my post,I see I failed to mention that. I definitely would not want to experiment with it as you suggest. I operate on 40 meter band alot,…around 7.238 to 7.274 mhz! I use an external antenna tuner and keep SWR flat at 50 ohms,…or no more than 1.5:1 SWR,…if that means anything or would have any effect in causing an RF burn,…I don’t care to find out,either!

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