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Author Topic: Bodies and cell towers?  (Read 4234 times)

Don Haines

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Re: Bodies and cell towers?
« Reply #15 on: February 27, 2013, 07:38:13 PM »
Definitely. Everybody (well, almost) knows you shouldn't microwave live animals if you don't want 'em to die - and this is the same sort of radiation. Of course, it is a LOT less radiation, but while your car isn't totalled, that doesn't mean you don't get scratches in the paint.

If bvukich can botch an metaphor, so can I! :P

actualy..... your microwave oven is a lot less power than what is fed into a cell-phone node...
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Re: Bodies and cell towers?
« Reply #15 on: February 27, 2013, 07:38:13 PM »

brianboru

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Re: Bodies and cell towers?
« Reply #16 on: February 27, 2013, 08:25:50 PM »
Wow was it hard to find a reference to the invention of the microwave oven from a reputable source that has the melting chocolate bar story:

http://www.ieeeghn.org/wiki/index.php/Microwave_Ovens

I remember my electro-magnetism prof mentioning as a soldier in WWII standing in front of radar installations to get warm. (He was a bit odd.)
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tpatana

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Re: Bodies and cell towers?
« Reply #17 on: February 27, 2013, 10:10:00 PM »
So much info here that's not really accurate, some good also, but let me clarify a bit.

In general, you can't get too much on your body. If you can, you're doing something you shouldn't, like climbing on the tower, hugging the actual antenna element, or something similar. Especially if you're below the antenna level (more than say 20feet/6 meter), quite often the beam is directed above you, and the signal level is much less compared to same distance from the antenna but at same height than the antenna. That's not always the case, but usually. The antenna beam is formed that way to get maximum distance for the signal, no point beaming it to the ground close to the tower. Makes sense, right.

So #1, you're likely safe. 99% of the time you get more cell signal radiation from the one you hold on your ear, and that's why they have the SAR-test on the phones, with certain maximum limit they have to pass or FCC don't allow them to be sold. New phones are much much better on SAR than late-90 phones. So you're safe with your cell phone too. Unless you use the old POS from 90s, and they didn't kill anyone either.

As for equipment, it's still highly unlikely, but it is possible to get interference or even malfunction. Most electronics are tested towards certain type of radiation, both different frequency and power. On top of my head I can't recall the typical levels they test, but I think they are not that strong. So depending on the equipment, how well it was shielded and such, it might cause something if you are too close to the beam. Again, being below the tower helps compared to being same level with the antennas. Again, in most cases, not always.

I'm trying to think if it could cause permanent damage, but it should try to corrupt the FW in one way or another, and that's one step more difficult. So I'd say you're safe on both accounts, you and your gear, but if you see something odd behavior, turn off the camera and find position with less beam. Most likely you don't get anything.

dbduchene

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Re: Bodies and cell towers?
« Reply #18 on: February 28, 2013, 09:14:45 PM »


actualy..... your microwave oven is a lot less power than what is fed into a cell-phone node...
[/quote]

I do not know how you came up with this but it just is not true. Most Cell transmitters are 70 watts. at 800 Megs or 1.9 gig Microwaves are 800 to 1200 watts and highly focussed at 2.4 gig. (same as your wifi, Blue tooth and many other things) I made my living through most of the 90s climbing cell and other two way towers.

To the OP's question there is no way to answer your questions without knowing a lot of info that you do not have a way to provided us. It may be a bad place to be and it may be OK it just depends on a LOT of things. The chances of it doing something that would kill your camera is very low.

« Last Edit: February 28, 2013, 09:16:30 PM by dbduchene »
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Don Haines

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Re: Bodies and cell towers?
« Reply #19 on: February 28, 2013, 10:52:44 PM »


actualy..... your microwave oven is a lot less power than what is fed into a cell-phone node...

I do not know how you came up with this but it just is not true. Most Cell transmitters are 70 watts. at 800 Megs or 1.9 gig
[/quote]
I was thinking peak and your number sounds about right for average.  I was told that the tower on site is peak power of 1000 watts per cell and the waveform has a peak to average ratio of 8db... That would make an average power during transmission of about 150 watts, and since it does not transmit continuously, and guessing a 50 percent duty cycle, that would be 75, your number being 70
« Last Edit: February 28, 2013, 11:20:33 PM by Don Haines »
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LetTheRightLensIn

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Re: Bodies and cell towers?
« Reply #20 on: March 01, 2013, 05:26:06 PM »
Question to all our physics and engineering experts here: I found an interesting location that is at the top of a building with cell phone transmitters attached to it. I think they're for major US carriers in case the frequencies used make a difference.

The place has the usual warning signs a la "may exceed the usual blahblah". From a medical standpoint I'm certain that it's a no-issue. But what about camera gear? I guess I might not want to use wireless triggers there but anything else at risk?

Thanks

I drove up to Mt. Wilson, they have tons of transmitting towers up there. Got out walked around a bit. Went back to the car and used the clicker to try to unlock it, click, click, click, nothing! Even from 1" away NOTHING! Thank god it wasn't one of those cars that has no physical key mechanism or I would've be shafted. And it did make you wonder what was beaming on you up there. I've never had a key clicker fail to open something from a few feet away never mind still failing at just 1-2" inches away!

« Last Edit: March 01, 2013, 05:32:43 PM by LetTheRightLensIn »

Don Haines

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Re: Bodies and cell towers?
« Reply #21 on: March 01, 2013, 06:08:15 PM »
Question to all our physics and engineering experts here: I found an interesting location that is at the top of a building with cell phone transmitters attached to it. I think they're for major US carriers in case the frequencies used make a difference.

The place has the usual warning signs a la "may exceed the usual blahblah". From a medical standpoint I'm certain that it's a no-issue. But what about camera gear? I guess I might not want to use wireless triggers there but anything else at risk?

Thanks

I drove up to Mt. Wilson, they have tons of transmitting towers up there. Got out walked around a bit. Went back to the car and used the clicker to try to unlock it, click, click, click, nothing! Even from 1" away NOTHING! Thank god it wasn't one of those cars that has no physical key mechanism or I would've be shafted. And it did make you wonder what was beaming on you up there. I've never had a key clicker fail to open something from a few feet away never mind still failing at just 1-2" inches away!
I assume it worked later...

If you are near a powerful source of rf it can overload the front end of the car's receiver, everything gets clipped and nothing gets decoded. I work 19 kilometers away from a transmitter tower which blasts out 30 megawatts of tv, fm radio, and various emergency transmitters. We need to put filters on all of our hf band receivers or all we get is AM 1200, no matter where it is tuned, if the antenna is rotated anywhere near the tower
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Re: Bodies and cell towers?
« Reply #21 on: March 01, 2013, 06:08:15 PM »