Subject: Is this part of Sutro??? (Bowling)(Schuyler)(Philips).. Date: Sat, 27 Nov 1999 125625 -0600 (CST) From: "Roy L. Beavers"To: emfguru -------------------------------------------------- ---------- Forwarded message ---------- Date: Sat, 27 Nov 1999 19:02:52 From: Alasdair Philips To: "Roy L. Beavers" Subject: Re: Is this part of Sutro??? (Bowling)(Schuyler).. A point of info from the UK: We have some 500 kW long-wave AM transmitters and quite a lot of 200 kW Medium waveband AM transmitters. I would be surprised if other countries didn't also have such high powered AM transmitters. 50 kW on Short-Wave band may be about maximum. The 500 and 200 kW transmitters ARE mainly near centres of population. Cheers Alasdair >Jim Schuyler of STAC replied: > >It is very common for a "clear channel" radio station such as KGO to be >received all over the continent and further (at night), due to the way >low frequency AM radio signals propagate. Same is true of many >commercial stations in the midwest, and the east. I think that 50kw is >about as high a power as is permitted for AM broadcast...and probably all >that's actually needed to reach most of the nation at night. During the >day you wouldn't be able to receive KGO, of course, unless the signal >goes thru a ``repeater,'' which is common for FM and for TV. > >Amateur radio operators, who are increasingly aware of potential EMR >problems, communicate around the world on 100 watts radiated power (at >higher frequencies than commercial AM). When I was first licensed (I'm a >part of the civilian emergency response teams here in SF and that's the >only time I use it) I remember old ``hams'' holding a 60 watt bulb in >their hands (not plugged in), near a transmission line (going to an >antenna) and watching the bulb light up. Reminds one of the Curies >x-raying their hands. That would not be common practice today - hams are >very aware that there might be a hazard here and keep to the lowest >operating power necessary to achieve the desired result - in fact that's >the way the regulations read. > >[.......guru says: It is largely because of the efforts of Dr. Sam >Milham, of this list, that the "regulations" regarding the operation of >HAM radios have been tightened......] > >It is primarily FM and TV coming off of Sutro that causes problems for >locals, and the range of pure EMF interference with garage door openers, >car alarms, TVs, radios, phone, is probably around a half mile. >Bio-interactions, of course, unknown. > >----------------------------------------------------------- >Sutro Tower Action Committee >An action group providing information regarding Sutro Tower >expansion, safety, and community issues. >http://www.sutro.org/ EMail to: stac@sutro.org > > ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Alasdair Philips, BSc(Eng), DAgE, MIAgE Director, UK Powerwatch, (aphilips@gn.apc.org) EMC Engineer and EMF-bioeffects researcher ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Archive provided courtesy of WaveGuide, http://www.wave-guide.org Reprinted with permission of Roy Beavers, http://www.emfguru.com