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    Flashaholic* LowBat's Avatar
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    Question How do I detect and measure RF/EM radiation?

    I maybe moving next to a rather large communications tower. I'm wondering what sort of radiation sould I be concerned about and how do I measure it? I'm guessing radio frequency energy and perhaps electro-magnetic radiation are what I need to be looking for. As I know very little about this stuff, I thought I'd see if we had some expects on board who could enlighten me. I'm also guessing a geiger counter isn't the right measuring device for this type of radiation.

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    Flashaholic* carbine15's Avatar
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    Default Re: How do I detect and measure RF/EM radiation?



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    Flashaholic* London Lad's Avatar
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    Default Re: How do I detect and measure RF/EM radiation?

    Might be cheaper to move !


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    Flashaholic* LowBat's Avatar
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    Default Re: How do I detect and measure RF/EM radiation?

    That looks expensive and complicated. I'd venture to say the manual would probably resemble a phone book. Anything a little simpler for a novice like myself?

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    Flashaholic* Lasernerd's Avatar
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    Default Re: How do I detect and measure RF/EM radiation?

    AM radio hooked to Spectrum labs software
    http://oathkeepers.org/oath/join/
    Which LEO' here agree with this??

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    Flashaholic* Steve K's Avatar
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    Default Re: How do I detect and measure RF/EM radiation?

    It depends on what sort of concerns you have.

    If you are worried about violations of FCC regulations, just verify that your radio, TV, cell phone, cordless phone, etc. still work okay. If there's no degradation in their performance, then you are fine.

    If you are worried about health issues, then I'm not sure what to tell you. Are there any standards? I'm betting that there are some standards regarding how much RF a microwave oven can emit, and I think there are some affordable instruments to measure this emission. Other than this, you may be left with more empirical sorts of experiments. For instance, if you can take a hot dog out of the fridge, set it on a plate on the counter, and it cooks just sitting there, then you probably have a problem with microwave emissions. :-)

    Those are all of the low-cost options that I can think of. The proper way to measure RF levels is indeed to use a spectrum analyzer, and that's not cheap. There are places that rent this sort of equipment, if you are interested. And then there's the question of what level of RF is acceptable. I know the specs for the industry that I work in, but I'm sure that the requirements for (intentional) broadcasting is different.

    good luck,
    Steve K

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    Default Re: How do I detect and measure RF/EM radiation?

    Hi Lobat Go to www.trifield.com and check out the "trifield meter". At $ 145.00 these work very well and have been around for years. Not a Lab Standard but will do what you want quite well.

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    Flashaholic* carbine15's Avatar
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    Default Re: How do I detect and measure RF/EM radiation?

    i read of some studies that showed a correlation between increased beta radiation and healthier offspring, longer lives and fewer diseases. If there's no annoying buzzing sound you should be fine. That buzzing sound is your brain frying, plus it's really annoying.
    Last edited by carbine15; 12-06-2006 at 04:53 PM.


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    Flashaholic* LowBat's Avatar
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    Default Re: How do I detect and measure RF/EM radiation?

    I just want to get a general idea of exposure levels. It sounds like that trifield meter is about what I'm looking for.

    Thanks everyone!

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    *Flashaholic* PhotonWrangler's Avatar
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    Default Re: How do I detect and measure RF/EM radiation?

    Quote Originally Posted by LowBat View Post
    I just want to get a general idea of exposure levels. It sounds like that trifield meter is about what I'm looking for.

    Thanks everyone!
    I've had a TriField meter for years and I like it. While it's not going to be anywhere nearly as sensitive as the labratory grade instruments, it will tell you if there's an unusually large amount of RFI or EMI in the immediate area.

    Having said that, RF energy falls off in intensity with the inverse-square law. In other words, as soon as it leaves the antenna, the field strength goes way, way down.

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    Flashaholic* hopkins's Avatar
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    Default Re: How do I detect and measure RF/EM radiation?

    Hi Tedtheled - There was the scifi novel 'The Terminal Man' about putting
    wires into a guys head to control his violent seizures. No inverse square
    law reduction for that situation.
    Whats seems to true is that people can think themselves sick as well as
    spontaneously cure themselves, ie the placebo effect.
    So lets not worry about low power RF from flashlights.

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    Default Re: How do I detect and measure RF/EM radiation?

    We have to do EMI testing in our products. The product is fired up and a directional antenna is pointed at the object from a set distance. The antenna is attached to a spectrum analyzer where a spectrum sweep is performed. We always pick up a couple of local strong radio stations but they are ruled out because we do an ambient reading first with the unit under test not operating and then subtract the ambient reading when testing with the device on. Let me tell you, it can be a pain in a butt to find and seal the emi leaks in some of the devices.

    Not sure of a home EMI cost effective testing solution.
    I live in a van down by the river

  13. #13

    Default Re: How do I detect and measure RF/EM radiation?

    Geepondy,
    There's an old saying amongst those of us that have to take prototypes and make them EMC compliant, "Ambients are my friend." More than once I've blazed through a certification test because of the ambients "hiding" a few problem frequencies.

    LowBat,
    For the most part RF energy decays as a square root of the distance that you are away from the transmitter (this holds mostly true for unidirectional xmtrs, I believe.) Meaning, if you're 10ft away from the transmitter, then move to 20ft away (a doubling of the distance) the power falls off by the inverse of the square root of the distance you moved away, or 1/sqrt(10). You can see that it doesn't take too long to get really small numbers.
    You're subjected to MUCH greater levels of RF by putting a cell phone right next to your brain!


    Ordin
    ...Everything I know about the light at the end of the tunnel I learned from Wiley E. Coyote...

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    Flashaholic* hopkins's Avatar
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    Default Re: How do I detect and measure RF/EM radiation?

    A simple way to detect RF is with an AM radio. Walk around your home with
    a portable AM radio, turned up loud and hold it near your computer monitor,
    television, fluorescent lights, electric bed blankets, microwave ovens,
    cell phone LCD displays, digital wrist watch, Regulated LED headlamps,
    digital camera, etc.

    Some devices emit RF when turned OFF but plugged in an AC outlet.

    -notice non-regulated LED lights do not emit RF.

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    Default Re: How do I detect and measure RF/EM radiation?

    well for what's it's worth I know when the Navy is on high alert because they increase the radar power which causes tiny interference dots on my DTV screen.. they are tiny little dots, about the size of a period. "." and are distributed in a 'dancing' grid pattern across the screen.. it's ominous when they appear, sometimes at night, you wonder what they're searching for out there..

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    *Flashaholic* James S's Avatar
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    Default Re: How do I detect and measure RF/EM radiation?

    is it just a cell phone tower? Those things are pretty closely regulated and even with a bazillion people using transmitters a few inches from their brain the studies that might show an effect are still so close to the nose level that there is unlikely to be any real effect there. So your exposure by living near a tower where you're a lot further from the transmitters isn't likely to do anything bad to you at all even over the long term. At least according to any of the current data.

    you will want to read the wikipedia article on the Inverse Square Law and understand that your exposure will be very small.

    It's really not worth stressing over. If there were a real effect of living under the thing it would show up quite clearly on the data. Afterall there are a LOT of these things, especially in urban areas where people often live right inside an apartment with the antennas mounted right outside their bedroom windows.
    -James

    E=sqrt((mc^2)^2+(pc)^2)

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    Default Re: How do I detect and measure RF/EM radiation?

    the electrical activity of the brain is so tiny that the most sensitive instruments man has made are needed to measure the magnetic fields they produce outside (!) the brain. see the 'squid' device-- http://www.lanl.gov/quarterly/q_spri...uid_text.shtml

    a little research turns up much to indicate that magnetic fields applied to the brain most definitely affect thought, and even the ability to discern truth from falsehood. I can't help thinking that the immense magnetic fields present in everyday life both man made and cosmic have a profound affect on our brains..
    Last edited by TedTheLed; 11-18-2007 at 09:05 PM.

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