Further to John's comment, with which I wholly agree...
In 1994, the BBC presented a paper to CEPT Project Team SE21, in which they
looked at the field strengths of TV signals in London. The 4 TV channels
provided between 200 to 500 millivolts/metre each channel for over 400,000
people. The resulting peak field strength is therefore over 1 volt/metre, just
from the TV tx's, let alone other BC. The exposure has been for over 30 years.
Even allowing for some big variations, it's very hard to see where any
significant effect would not have become apparent by now.
That's for a frequency close to the cellular bands. Wayne Green in 73 Magazine
at one time was suggesting that the magnetic field radiated by power
transformers could be a problem, so that big amplifiers should be kept well away
from the operator. Now I bet the AC magnetic field around the drivers of
numerous electric trains spread over Europe is high enough and the exposure long
enough, to have shown any dubious effects by now.
The classic case of hysteria on this appeared here a few years ago, where a 9
year old girl was alleged to be hyperactive because of the RF from an antenna on
a water tower. A 'researcher' from a university 'detected radio waves in her
bedroom'. The hyper activity ceased when the antenna was removed. However, there
hadn't been any equipment on the end of the feedline for 3 years.....
73
Peter G3RZP
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