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#1
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Hi,
With a friend we have to install a beam near a HV Power line (we ignore its power) located 300 m from the QTH. Has someone among you a chart or table listing the EM field and Electric field of various HV power lines ? I know that a HV power line (I don't know its power) displays e.g. an EF of 10 kV/m and an EM flux density of 10 microT. and that the field decreases like 1/r^2 and that there is a epidemiological risk from 2 miligauss. I also know that the administation denies any construction in the 50m around such HV line due to the risk for the health But these are all data I have. Not enough to appreciate to risk of this specific installation. My questions are : - Is there a risk that this HV power line disturbs DX QSOs in HF bands (and QSO in VHF, but here I doubt much) - What is the risk for the health at such a distance according to the voltage ? Thanks in advance Thierry, ON4SKY http://www.astrosurf.com/lombry |
#2
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On Wed, 5 Jan 2005 22:14:45 +0100, "Thierry" See LUXORION website
wrote: With a friend we have to install a beam near a HV Power line (we ignore its power) located 300 m from the QTH. Hi Thierry, It never bothered me or my buddies. 73's Richard Clark, KB7QHC |
#3
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Thierry wrote:
Is there a risk that this HV power line disturbs DX QSOs in HF bands .... At my QTH, the power lines render a vertical virtually useless. I suspect it is the vertical ground wire on a pole-mounted capacitor that is the culprit as it is close to 1/4WL on 40m. -- 73, Cecil http://www.qsl.net/w5dxp |
#4
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![]() "Thierry" See LUXORION website wrote in message ... Hi, With a friend we have to install a beam near a HV Power line (we ignore its power) located 300 m from the QTH. Has someone among you a chart or table listing the EM field and Electric field of various HV power lines ? I know that a HV power line (I don't know its power) displays e.g. an EF of 10 kV/m and an EM flux density of 10 microT. and that the field decreases like 1/r^2 and that there is a epidemiological risk from 2 miligauss. I also know that the administation denies any construction in the 50m around such HV line due to the risk for the health But these are all data I have. Not enough to appreciate to risk of this specific installation. My questions are : - Is there a risk that this HV power line disturbs DX QSOs in HF bands (and QSO in VHF, but here I doubt much) - What is the risk for the health at such a distance according to the voltage ? Thanks in advance Thierry, ON4SKY http://www.astrosurf.com/lombry By microT I assume you mean microTesla. One Tesla is 10,000 gauss. So 10 uT is 100 milliGauss, 50 times more than your statement about epidemiological risk. But I can't answer your questions. Sorry. John |
#5
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Hi,
Well, I receive some answers, found others on the Internet, all is now written in my 3 pages (see ref below). The big pictu There is surely no influence of HV power lines at 300m away. And probably no QRM on HF bands at that distance either. But will know more about HF consequences when will be on the air in the field...;-). I retain the idea of Cecil on 40m. No study can confirm the direct relation between some leukemia and HV power lines located to say 100m from houses. There are leukemia observed with radiation equivalent to a exposure to an HV power line 75m away. On the other hand, companies recognize that beneath pylons (25m away) there is a risk for the health (and some electrical devices) due to the strong current and voltages, far higher than the current limits (see end p3 of my text,under guidelines) which are thermselves, already 50 or 100x higher to the values potentially at risk for security reasons. But I don't see how we could contact a leukemia without a durable exposition. It doesn't come eating your familiar food and cookies... or half the population 'd be contaminated. As around the concerned spots studied by IRPA there is no other powerful sources of emission excepted these sad pylons... At last, the risk is not black or white depending on the distance or the radiation level. All this is progressive and hard to define, hence the deep fog envelopping all studies. WHO is currently studying the problem more deeply. More info of my site with many links and some books to read. http://www.astrosurf.com/lombry/qsl-em-radiation.htm, tables p2, ref p3 73 Thierry, ON4SKY |
#6
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![]() "Thierry" - wrote in message ... Hi, Well, I receive some answers, found others on the Internet, all is now written in my 3 pages (see ref below). The big pictu There is surely no influence of HV power lines at 300m away. And probably no QRM on HF bands at that distance either. snip Thierry: Our rule is that any power line which is line-of-sight from the antenna is capable of causing interference on HF. See: http://www.arrl.org/tis/info/HTML/power_line_handbook/ for more information. -- Crazy George Remove N O and S P A M imbedded in return address |
#7
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![]() "Crazy George" wrote in message ... "Thierry" - wrote in message ... Hi, Well, I receive some answers, found others on the Internet, all is now written in my 3 pages (see ref below). The big pictu There is surely no influence of HV power lines at 300m away. And probably no QRM on HF bands at that distance either. snip Thierry: Our rule is that any power line which is line-of-sight from the antenna is capable of causing interference on HF. See: http://www.arrl.org/tis/info/HTML/power_line_handbook/ Many thanks George I was just visiting ARRL's TIS but I did't find this link. Some readings for my evenings ;-) Thierry for more information. -- Crazy George Remove N O and S P A M imbedded in return address |
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