HF antenna and Power line ?
 

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

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

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

"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

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

"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

"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