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Thread: How powerful would a radio signal have to be to feel it as vibrations on the skin?

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    Default How powerful would a radio signal have to be to feel it as vibrations on the skin?

    Hi,

    How powerful would a radio signal have to be to feel it as vibrations on the skin?

    Is there a way to measure the presence of any radio signals in a given area i.e. the room of a house?


  2. #2
    Super Moderator 5B4AJB's Avatar
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    Quote Originally Posted by Health&Footwear View Post
    How powerful would a radio signal have to be to feel it as vibrations on the skin?
    It really depends on the frequency - it'd have to be pretty high, say, microwave and also pulsed to feel like vibrations.

    Quote Originally Posted by Health&Footwear View Post
    Is there a way to measure the presence of any radio signals in a given area i.e. the room of a house?
    Yes, it's called a field strength meter, an incredibly simple circuit you can make for next to nothing...
    Last edited by 5B4AJB; Tue 6th Feb 2018 at 20:48.

  3. #3

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    I agree a field strength meter would do it.
    Every ham who homebrews ought to have one, that in conjunction with an antenna analyzer is essential to really know what your antenna is doing. IMO

  4. #4

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    I'm assuming you are asking because you believe you can feel it, and suspect it might be high in your room, maybe because of a local source?

    Radio waves will either pass through you, or be absorbed. If they are absorbed the energy has to go somewhere and it gets converted to heat - this is how your microwave works. 700W of radio energy gets squirted into your oven, and that's what cooks the food. If you were stupid enough to punch a hole in the door, it would escape, but it disappears quickly - If it measured as 10 units a foot away from the oven, if you move the meter to 2 feet, it would be 2.5, and then at 4 ft it's down to .625, and at 8ft it less than .2 - so it runs out of steam very quickly.

    Radio waves less than 600MHz or so are not considered capable of heating unless they are VERY strong, like standing next to the antennas of a Radio 2 transmitter. Above 600MHz you would feel it heating you - so standing in front of a 10MEGA Watt radar would be toasty very quickly, but living across the road from the Radio 2 transmitter would be hard to measure.

    RF will burn if very strong, which obviously hurts but you do not feel pulsing, or tingling - or at least, I never have when working with it. It's essentially electrical AND magnetic energy - so metallic objects can be affected. Humans are mostly water, so we are pretty good at stopping radio waves passing through us. Certain parts of your body can be damaged by microwave , or close to microwave energy - your eyes, in particular, but people who work with this kind of thing use distance as their first line of defence - but its standard to power transmitters down when working ion aerial systems unless they are low power. Low power in this context is linked to frequency. 400W from a radio hams HF radio wouldn't bother me too much, although some of the antenna parts can be quite high voltage, and the chances of a shock are certainly possible. 400W from a microwave oven with the hole in the door would have me avoiding being in the room. The high power signals from cellphone towers is not something to be happy with climbing up a ladder, but across the rd? No problem.

    What's the background to your question - sounds interesting?

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    K7KBN's Avatar
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    To feel it "as vibrations on the skin", you wouldn't have to go much above a few kilohertz. Even then, it wouldn't be a "radio" signal but an audio frequency generator source. Unless I'm completely misunderstanding what you want.

    Do you want to be able to feel the individual "vibrations"?
    73
    Pat K7KBN
    Semper ubi sub ubi.

  6. #6

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    I'm thinking he feels vibrations on the skin and wishes to link this to the possibility of radio waves causing it - which of course is something quite different.

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