radar and health ?
 

Hi,

I received this message from a colleague but I cannot answer him. I d
not know these systems.
Could you help me ?

My company has installed a Radar Tower for Port survaillence. The tower
is about 50 meter height on top of the of a 3 stories building roof and
my office building just below the tower on the same level, 20 meter away
from the tower. At the same time, the surrounding is my working area (
Jetty Terminal for ships loading and unloading activities ). I can say
that I'll be around that area 12 hours a day for another 20 years.

My question:

Is it safe to work in that area????

Thanks in advance
Thierry
http://www.astrosurf.org/lombry


--
Posted via Mailgate.ORG Server - http://www.Mailgate.ORG

radar and health ?
 

On Sat, 7 Jan 2006 15:47:01 +0000 (UTC), "Thierry"
wrote:
My company has installed a Radar Tower for Port survaillence. The tower
is about 50 meter height on top of the of a 3 stories building roof and
my office building just below the tower on the same level, 20 meter away
from the tower.

When I was a lad in Electronics School
They tied my ass to a students stool.
A radar was operating just 20 feet away;
And with each turn it pointed our way.

We thought it was just to test the running gear.
Certainly we never considered it with fear;
But when the TV in the corner sizzled with each pass,
We counted revolutions to the end of class.

At the same time, the surrounding is my working area (
Jetty Terminal for ships loading and unloading activities ).

In light of the fear, here's a piece of impudence:

I can say that I'll be around that area 12 hours a day for another 20 years.

My question:

Is it safe to work in that area????

No, the industrial sound level will undoubtedly lead to hearing issues
later in life (if you survive the radiation).

73's
Richard Clark, KB7QHC

Apologies to Gilbert and Sullivan and "The Monarch of the Sea"

radar and health ?
 

Hi Thierry

I dont have the answers on hand. There are however exposure limits set
by legislation in various countries. You will often find websites that
help you determining what the conditions are at your location. Amateur
radio stations for example meed to be concerned about EMR levels when
the radiated power gets high.

If you cant find anything on your countries radiocomm authorities site
have a look at the US's FCC or Australia's ACMA sites. The exposure
limits tend to be a fairly universal thing. I would suggest too that to
license such a radar structure a EMR study would have to be done as a
matter of course. This is a important part of spectrum and safety
planning that is certainly the norm in Australia.

I would suspect too that being used for ships at short range the output
power would not be nowhere near what is used at longer distances. If
perchance it is used for longer range as well, then the antenna system
would be designed in such a way that most of the radiated power is
horizontal and as such only a small component would be aimed down at
your office/work location. This is the same logic as placing a cellphone
antenna up very high so that nearby EMR is not an issue.

My gut feel is that it is safe. You havent of course provided power and
antenna pattern figures for the installation.

Cheers Bob W5/VK2YQA

Thierry wrote:


My question:

Is it safe to work in that area????

radar and health ?
 

Thierry wrote:

Hi,

I received this message from a colleague but I cannot answer him. I d
not know these systems.
Could you help me ?

My company has installed a Radar Tower for Port survaillence. The tower
is about 50 meter height on top of the of a 3 stories building roof and
my office building just below the tower on the same level, 20 meter away
from the tower. At the same time, the surrounding is my working area (
Jetty Terminal for ships loading and unloading activities ). I can say
that I'll be around that area 12 hours a day for another 20 years.

My question:

Is it safe to work in that area????

Thanks in advance
Thierry
http://www.astrosurf.org/lombry

--
Posted via Mailgate.ORG Server - http://www.Mailgate.ORG

I have spent most of my working life around various RADARs starting in my
late teens at the Royal Radar Research Establishment; which was flooded with
RF from numerous operating systems on a large variety of frequencies -
throughout much of the establishment a neon bulb would often light just from
the RF environment.

The last 25years or so before retirement were in a building with numerous
installations, including a long range L band ATC primary and secondary
installation which provided some entertainment in idle hours as I computed
the radiation pattern - with a surprising degree of accuracy - from the
noise emanating from my office radio as the beam swept by.

Across the hall was a lunchroom with a large health and safety warning sign
on the door that a microwave oven was in the room. Looking out the window
one was staring down the throat of an operating marine RADAR less than 30
feet away!!

To the best of my knowledge no one who worked there has developed any
strange illness that even rumour has related to the RADARs. I retired 10
years ago and have no significant illness.

Oh yes, and my kids seem to be relatively normal. (Maybe because I wore
aluminum underwear?)

Dave

radar and health ?
 

In article
lgate.org,
"Thierry" wrote:

Hi,

I received this message from a colleague but I cannot answer him. I d
not know these systems.
Could you help me ?

My company has installed a Radar Tower for Port survaillence. The tower
is about 50 meter height on top of the of a 3 stories building roof and
my office building just below the tower on the same level, 20 meter away
from the tower. At the same time, the surrounding is my working area (
Jetty Terminal for ships loading and unloading activities ). I can say
that I'll be around that area 12 hours a day for another 20 years.

My question:

Is it safe to work in that area????

Thanks in advance
Thierry
http://www.astrosurf.org/lombry

Oh yea, you gonnies are going to shrink up, and you winkie is going to
fall off......for sure.....

you

radar and health ?
 

On Sat, 07 Jan 2006 11:16:13 -0600, Bob Bob wrote:

I would suspect too that being used for ships at short range the output
power would not be nowhere near what is used at longer distances.

Hi Bob,

Probably only about 100KW peak, perhaps half a million.

73's
Richard Clark, KB7QHC

radar and health ?
 

If the radar antenna is 50m above your friend's level he'll be well
below the main beam.

While radars do typically have very high peak power outputs they only
transmit for a very brief fraction of time then shut off while they
listen for the echoes coming back from the
ships/planes/trains/automobiles/some clod walking his dog/what have
you. This drops the effective power output to a low level. As the
only demonstrated effect of radio waves is thermal (that is to say
they'll heat you up). the end effect isn't much diferent than what
you'd get from somebody shining a flash light at you from some
distance away. If your friend is worried about cancer lots of people
have tried to prove radio waves can do this but it hasn't been
reproducibly shown yet. If there is a link I'd think the research
would have conclusivly proven it by now. Have a look here-

http://www.mcw.edu/gcrc/cop/cell-pho...Q/toc.html#23B

This is really aimed at cellphone installations but the same general
ideas apply.

H.




On Sat, 7 Jan 2006 15:47:01 +0000 (UTC), "Thierry"
wrote:

Hi,

I received this message from a colleague but I cannot answer him. I d
not know these systems.
Could you help me ?

My company has installed a Radar Tower for Port survaillence. The tower
is about 50 meter height on top of the of a 3 stories building roof and
my office building just below the tower on the same level, 20 meter away
from the tower. At the same time, the surrounding is my working area (
Jetty Terminal for ships loading and unloading activities ). I can say
that I'll be around that area 12 hours a day for another 20 years.

My question:

Is it safe to work in that area????

Thanks in advance
Thierry
http://www.astrosurf.org/lombry

radar and health ?
 

OK Thanks Howard and the others.
I have well an article on my website about EMR and health but I hadn't
data about radar.

Still thanks
Thierry

radar and health ?
 

I don't understand being "on the same level" AND being "20 feet below".

73, Steve, K,9.D;C'I

I've been working in RF and transmitters for many years and I can say that
there are absolutely no side eff eff eff effects.
*(:-)


"Thierry" wrote in message
oups.com...
OK Thanks Howard and the others.
I have well an article on my website about EMR and health but I hadn't
data about radar.

Still thanks
Thierry

radar and health ?
 

In article ,
"Steve Nosko" wrote:

I don't understand being "on the same level" AND being "20 feet below".

73, Steve, K,9.D;C'I

Seems that you don't understand the Antenna Beamwidths in the Horozontal
and Vertical Planes, on Modern Marine Radar Systems.

Me

radar and health ?
 

Thierry wrote:

Hi,

I received this message from a colleague but I cannot answer him. I d
not know these systems.
Could you help me ?

My company has installed a Radar Tower for Port survaillence. The tower
is about 50 meter height on top of the of a 3 stories building roof and
my office building just below the tower on the same level, 20 meter away
from the tower. At the same time, the surrounding is my working area (
Jetty Terminal for ships loading and unloading activities ). I can say
that I'll be around that area 12 hours a day for another 20 years.

My question:

Is it safe to work in that area????

Thanks in advance
Thierry
http://www.astrosurf.org/lombry




So, what about Radar then...

First, There are two "kind" of RF radiation, non-ionizing and ionizing and
effects emanating from very high voltage nearby different materials.

Normally, non-ionising is to be more or less compared to sun light.
An overdose of non-ionising radiation gives the same effects than sun stroke
gives you, you heat up your body and the same symptoms occur if overheated.

As long as you are not overheating, there should be no harmful effects on
you. The problem are always to determine a narrow angle beam, radiating
towards sensitive parts of the body, like brain and eyes. The long term
effects of a heated brain are probably still debated. However, it's
probably not good for you. A narrow angle beam does not give the same full
body heating that "switches" your body reaction as it's only a part of you
that gets overheated, not the whole body!
If you are stupid enough to look into a wavegiude with full power on, be my
guest!

Now then to the nasty part, the ionising radiation. This radiation creates
residual effects even after the emitted radiation is switched off.
Typically radiation like Gamma radiation etc. This kind of radiation could
also create secondare types of radiation from materials in the environment.

Treat the ionising radiation like plague or cholera, avoid avoid avoid.


Now, radar radiation is only non-ionising RF radiation, let be with high
intermittent power and sometimes with stupidly high power.
Looking into an active waveguide will probably burn off your eye nerve or
something very bad for you.

If you are standing near a RF radiating radar station, the average energy is
what heats you up and the peaks are so short that even if they are Mega
Watts, the average energy transfer to your body is low.

Going up in frequency more or less moves the RF towards light, still with
the same effects.

OK, so it's not that bad is it? No? Wrong! Some frequencies are really bad
for us because different parts of our bodies absorbs different amount of
energy on different frequencies.

Let's take a party example... Many key fobs, alarm buttons for car locks
etc, operates on 418MHz. It happens to be approximately where a normal head
are resonating... Try walking just about out of range for your alarm/lock
button for your car, point the key fob against your head and press the
unlock key, voila, in most cases, you increase the range of the key fob.

So what? Just be aware and take a look in the health and safet chapter of
the ARRL handbook. It's all there and also how much more dangerous it is
with different frequencies.

The safest place are almost always under an antenna so don't fret over the
mobile phone mast on the roof of the school! I would be more concerned if
it was on a neighbouring house...


Cheers


Dan / M0DFI

radar and health ? digressing to keyless remotes...
 

Some thoughts inserted in Dan's comments...***


"Dan Andersson" wrote in message
...
Thierry wrote:
...
My company has installed a Radar Tower for Port survaillence. The tower
is about 50 meter height on top of the of a 3 stories building roof and
my office building just below the tower on the same level, 20 meter away
from the tower. At the same time, the surrounding is my working area (
Jetty Terminal for ships loading and unloading activities ). I can say
that I'll be around that area 12 hours a day for another 20 years.
My question:
Is it safe to work in that area????
Thanks in advance
Thierry

So, what about Radar then...

First, There are two "kind" of RF radiation, non-ionizing and ionizing and
effects emanating from very high voltage nearby different materials.

*** Perhaps a typo, but the ionizing type is not a kind of RF
radiation. Ionizing radiation is nuclear radiation. This radiation is able
to strip electrons (and other particles) from atoms. RF does not do this as
we use it. It is unfortunate that we use the term "radiation" for both
things. In any case, it is not part of the original question.


Normally, non-ionising is to be more or less compared to sun light....

*** RF, Light is Electromagnetic radiation and produces, as far as we
know and can be proved, Heat.



As long as you are not overheating, there should be no harmful effects on
you. ...

*** Widely agreed, yet feared by many.


Now, radar radiation ...sometimes with stupidly high power....

** Not to the people USING it.



If you are standing near a RF radiating radar station, the average energy
is
what heats you up ...

*** Regardless of where/how you receive RF power, it produces a heating
effect. Standing in an open field, you are picking up RF from EVERY
transmitter within ear-shot (so to speak) and you have RF currents in your
body, but of course, the heat generated is infinitesimal. Tests have been
done to measure the low, yet measurable actual heating of things such as the
human face in the RF field of hand-held radio like power.


Some frequencies are really bad
for us because different parts of our bodies absorbs different amount of
energy on different frequencies.

*** The effect is that of heating and the most prominant effect is the
heating of the water content in things - us included. Water (H20) absorbs
RF best around 900 MHz and again around 2500 MHz. There may be more
frequencies, but these are the two used in microwave ovens (900 earlier and
2400 now - I believe). When it does absorbe it ( as opposed to reflecting
it, which it may do depending on how good the impedance match is) the water
heats. The old (possibly urban myth) story is of the radar techs up at the
old Dew Line Early warning radars would stand in fornt of the High power
radar antennas to warm up when working outside. The standard joke is that
they had small families after that...



Let's take a party example... Many key fobs, alarm buttons for car locks
etc, operates on 418MHz. It happens to be approximately where a normal
head
are resonating... Try walking just about out of range for your alarm/lock
button for your car, point the key fob against your head and press the
unlock key, voila, in most cases, you increase the range of the key
fob....
Dan / M0DFI

*** Mine is around 320 MHz. I seriously doubt that the head resonates
there, or has much of a resonance to speak of at any frequency. This
"range extending of the keyless remote" is easily duplicated by various
placements of your other hand, arm and other parts of the body, near the
remote. I play with it often walking across the parking lot to the car. It
can be best explained considering that being conductive, the body can pick
up RF from the fob and be an added part of the antenna in a
quasi-parasitic-element manner. The "antenna" in the fob is, at best, an
extremely poor one (not being anywhere near 1/4 or 1/2 a wavelength, nor
being a loaded antenna that is matched to the transmitter) and any help it
gets will frequently be observed as positive. This effect is very dependant
on things like polarization of the auto's receive antenna (if there is one
with a recognizable polarization), polarization of "you as an antenna",
direction (as the transmit pattern will most certainly be directional as
well as the receive pattern), and probably innumerable other complexities of
the RF environment you happened to be immersed in.

Any kind of a conductor can be brought close to the fob and have a similar
effect. I've done it with long screwdrivers and pieces of wire. Careful
placement of a half wave wire can achieve astounding range....comparatively
(to me, anyway, but then, there are those that say I am easily amused).
Nerd that I am, it's fun to see how much range you actually can get...just
for the bleep of it. I should get a life at times. (:-) Please no
agreement.

73, Steve, K,9.D'C;I

Oh yea...the origainsl Radar near the office question. Do a search on
something like the Russian radar illumination of the American Embassy. I
believe there are those that claim the Americans which the Russians were
radiating with Radar got irritable or some such symptom(s).

73

radar and health ? digressing to keyless remotes...
 

Steve,

Your assertion is simply not correct. You may be thinking of particle
radiation, such as electron (beta), neutron, proton, alpha, cosmic,
etc., but pure photon radiation can certainly be "ionizing". A
well-known example is ordinary medical x-rays. Ionizing photons would
not typically be called "RF", but there is no difference other than the
energy levels.

(I spent so much time in the early stages of my career dealing with
intense sources of ionizing radiation (photons) that I still glow in the
dark.)

Back to the original question, ordinary radar is clearly not "ionizing".
Not a good idea to be too close, due to possible thermal effects, but
otherwise no big deal.

73,
Gene
W4SZ

Steve Nosko wrote:
Some thoughts inserted in Dan's comments...***


"Dan Andersson" wrote in message
...


First, There are two "kind" of RF radiation, non-ionizing and ionizing and
effects emanating from very high voltage nearby different materials.


*** Perhaps a typo, but the ionizing type is not a kind of RF
radiation. Ionizing radiation is nuclear radiation. This radiation is able
to strip electrons (and other particles) from atoms. RF does not do this as
we use it. It is unfortunate that we use the term "radiation" for both
things. In any case, it is not part of the original question.

radar and health ? digressing to keyless remotes...
 

Gene Fuller wrote:
..., but pure photon radiation can certainly be "ionizing".

My ITT "Reference Data for Radio Engineers" says gamma rays
are EM waves which are certainly "ionizing".
--
73, Cecil http://www.qsl.net/w5dxp

radar and health ?
 

I think if it is too strong it will affect your eyes first, ears then
nerves/brain last. There are lots of safety precautions for wx radar on
aircraft and they are generally are under 10kw for small planes, x band
radar. Large jets, c band. Then there are fighter aircraft whose
targeting radar has been know to kill small animals around the runways.
But those are out of favour now, low power is in.



Thierry wrote:
Hi,

I received this message from a colleague but I cannot answer him. I d
not know these systems.
Could you help me ?

My company has installed a Radar Tower for Port survaillence. The tower
is about 50 meter height on top of the of a 3 stories building roof and
my office building just below the tower on the same level, 20 meter away
from the tower. At the same time, the surrounding is my working area (
Jetty Terminal for ships loading and unloading activities ). I can say
that I'll be around that area 12 hours a day for another 20 years.

My question:

Is it safe to work in that area????

Thanks in advance
Thierry
http://www.astrosurf.org/lombry

radar and health ?
 

Steve Nosko wrote:

I don't understand being "on the same level" AND being "20 feet below".

Yes confusing, but I am sure there are intense lobes to look out for.

radar and health ?
 

In article ,
Jules wrote:

I think if it is too strong it will affect your eyes first, ears then
nerves/brain last. There are lots of safety precautions for wx radar on
aircraft and they are generally are under 10kw for small planes, x band
radar. Large jets, c band. Then there are fighter aircraft whose
targeting radar has been know to kill small animals around the runways.
But those are out of favour now, low power is in.



Thierry wrote:
Hi,

I received this message from a colleague but I cannot answer him. I d
not know these systems.
Could you help me ?

My company has installed a Radar Tower for Port survaillence. The tower
is about 50 meter height on top of the of a 3 stories building roof and
my office building just below the tower on the same level, 20 meter away
from the tower. At the same time, the surrounding is my working area (
Jetty Terminal for ships loading and unloading activities ). I can say
that I'll be around that area 12 hours a day for another 20 years.

My question:

Is it safe to work in that area????

Thanks in advance
Thierry
http://www.astrosurf.org/lombry




The basic facts a Any commercial civilian Xband Radar will NOT even
come close to approching FCC RF Radiation Biologic Health Maximum
Radiation Power Densities even if you are right next to the antenna.
You are more likely to get hurt by the rotating antenna hiting you
in the head than from the RF Energy coming out of the antenna.
Wx Radar on Commecrcial Aircraft usually are left in Standby Mode
untill the aircraft has taxied onto the tarmac beside the active runway.
Eve if they were activated, most xBand versions still don't have the
Power Density one foot in front of the antenna to approch the FCC RF
Radiation Biologic Health Maximum.
Military Radars are a totally different beast altogether, and there are
very strict operational rules for when they can be operated inside US
Water and Airspace.

Me

radar and health ?
 

Me wrote:

The basic facts a Any commercial civilian Xband Radar will NOT even
come close to approching FCC RF Radiation Biologic Health Maximum
Radiation Power Densities even if you are right next to the antenna.
You are more likely to get hurt by the rotating antenna hiting you
in the head than from the RF Energy coming out of the antenna.
Wx Radar on Commecrcial Aircraft usually are left in Standby Mode
untill the aircraft has taxied onto the tarmac beside the active runway.
runway
Eve if they were activated, most xBand versions still don't have the
Power Density one foot in front of the antenna to approch the FCC RF
Radiation Biologic Health Maximum.
Military Radars are a totally different beast altogether, and there are
very strict operational rules for when they can be operated inside US
Water and Airspace.

On my plane the radar is 7.6 kw (xband). The manual says not to use it
on the ground especially around people. Also they have been know to
cause some sort of sparking on metal so fuel trucks are to be avoided.
Shop people are cautioned to make sure it is not emitting if in stby
mode, some do. The display will say STBY, the antenna not panning, but
it is emitting. Go figure. Small airplanes have xband not because it is
wimpy but because of antenna size constraints. These are 10 ro 12 inch
diameter "flat dish" antennas. Lots of waveguide-like openings on it.
Extreemly directional. And this is a small 6 seater plane.

Large weather radars, ground based are sband. Big antennas.

In the late 80's many radars dropped down to under 10 watts. Most under
one watt. Mainly due to improved signal processing. Even on large jets
with large dishes. With the lower power came more managable attenuation
affects in rain too.

You do not want your head one foot away from my radar when it is on. And
I wouln't let you try it, even if you asked.

radar and health ?
 

In article ,
Jules wrote:

Me wrote:

The basic facts a Any commercial civilian Xband Radar will NOT even
come close to approching FCC RF Radiation Biologic Health Maximum
Radiation Power Densities even if you are right next to the antenna.
You are more likely to get hurt by the rotating antenna hiting you
in the head than from the RF Energy coming out of the antenna.
Wx Radar on Commecrcial Aircraft usually are left in Standby Mode
untill the aircraft has taxied onto the tarmac beside the active runway.
runway
Eve if they were activated, most xBand versions still don't have the
Power Density one foot in front of the antenna to approch the FCC RF
Radiation Biologic Health Maximum.
Military Radars are a totally different beast altogether, and there are
very strict operational rules for when they can be operated inside US
Water and Airspace.

On my plane the radar is 7.6 kw (xband). The manual says not to use it
on the ground especially around people. Also they have been know to
cause some sort of sparking on metal so fuel trucks are to be avoided.
Shop people are cautioned to make sure it is not emitting if in stby
mode, some do. The display will say STBY, the antenna not panning, but
it is emitting. Go figure. Small airplanes have xband not because it is
wimpy but because of antenna size constraints. These are 10 ro 12 inch
diameter "flat dish" antennas. Lots of waveguide-like openings on it.
Extreemly directional. And this is a small 6 seater plane.

Large weather radars, ground based are sband. Big antennas.

In the late 80's many radars dropped down to under 10 watts. Most under
one watt. Mainly due to improved signal processing. Even on large jets
with large dishes. With the lower power came more managable attenuation
affects in rain too.

You do not want your head one foot away from my radar when it is on. And
I wouln't let you try it, even if you asked.




Jules, you really need to go back to Radar School and try and understand
the technology that your using. 7.6Kw Pulsed Xband Radars have an AVERAGE
Power of less than 20 watts. It isn't the Peak Pulse Power that fries
you, or causes the sparks, it is the AVERAGE Power, and less than 20
watts one foot in front of ANY antenna is considerably less than that,
due to RF Radiation being subject to the Inverse Square Law. Most of
the old Decca 20Kw Commercial Marine Radars in xBand had Average Powers
less that 35 watts, and were well below maximum Radiation Power
Densities directly in from of the 6ft Slotline Antennas.
Your socalled Flat Dish antennas at nothing more than a tuned Phase
Array, and again, one foot out in front, Power Densities are well
below maximum permissable Power Densities.

Third Generation Commercial xBand Radar Technology, that came in the
80's, introduced Solid State LNA's, Ring Circulating Isolators, and
Logrythemic IF ampilfiers, which improved the receivers Noise Figures,
and Dynamic Gain by an Order of Magnitude. This is all in the RF Path,
and had nothing to do with signal processing of baseband signals which
didn't come into play untill DSP Processors were intoduced in the mid
90's and the Fourth Generation of Commercial Radars.

Manuals are written by folks who understand the technology, about as
much as the lawyers, that approve them before they are published. Yes,
there are safety concerns with radar operations around FBO Fueling
Operations, but the incidents of actual causal problems, are rare to the
extreme.

Again, all the above is TRUE only for commercial radars, and may, or may
not be TRUE, and likely NOT TRUE for Military Radars, as these are more
often than not CW operating, and, or doppler type radars that are NOT
Pulsed.

Me

radar and health ?
 

Me wrote:
7.6Kw Pulsed Xband Radars have an AVERAGE
Power of less than 20 watts.

I know it works in pulses and it is the pulse you should look out for.
Like a microwave oven , it can induce voltages in pieces of metal, high
enough to cause sparks. What would that do to a person with a pacemaker?

I only know the power rating.
I am not sure arcing incidents are that rare as I have met a couple of
people who claim to have seen it happen.

If a hammer drops on your foot and then rests there for 20 minutes, is
it the pulse or the average force to look out for.

My radar...

Peak Power Output: 7.5 KW nominal, 6.0 KW minimum

Output Frequency: 9375 Mhz (X-Band)

I think it does 160 pulses per second.



You would be willing to take the full brunt of that one foot away? I
will be back at the airport this afternoon and ask for someone to hold
thier head up to the radome. I never went to radar school.

I'll take your word for it, but I won't volunteer!

radar and health ?
 

As an ex-RAF radar technician, during WW2 I have stood in the radar
beam, on many occasions, on the airfield runway and in the maintenance
workshop, just a few feet from the parabolic dish, of a 50 KW, 3
Gigahertz, airborne radar.

It was the radar which guided death-dealing machines to their targets,
the many incinerated German cities culminating in the innocent city of
Dresden - entirely destroyed just to educate the Russians whose tanks
were only a few hours away.

I was not warned of the possible dangers of such exposure. The powers
that be were not aware of them either in those days.

I am now in my 81st year. Still alive. I have fathered 5 healthy
children and have grandchildren. Draw your own conclusions about the
real dangers of electromagnetic radiation.
----
Reg.

radar and health ?
 

"Dot" wrote in message
...
On Sat, 4 Mar 2006 19:31:01 +0000 (UTC), "Reg Edwards"
wrote:

I am now in my 81st year. Still alive. I have fathered 5 healthy
children and have grandchildren. Draw your own conclusions about
the
real dangers of electromagnetic radiation.

In the interests of caution and safety... I would congratulate you
on
becoming an octogenarian, having a fine brood of kids and grandkids,
and I'd
wish to be so lucky... but then I'd remind you just how darned lucky
you
are.
========================================

I'm not lucky. I'm just an ordinary person. My genetic history
remains unaffected by high-power electromagnetic radiation. On the
contrary, it seems to have done me good!

But if I should eventually die with a brain tumour no doubt my
electromagnetic history will unjustly be blamed. ;o)
----
Reg.

radar and health ?
 

Incidentally, in 1945, I was an unsuspecting guinea pig sent to the
radioactive aftermath of Hiroshima for a week or so.

Again, my genetic history appears to have remained unaffected.
Perhaps, as you say, I am lucky.

I am just another very minor statistic, like everybody else, in the
field of statistics and probability. See the widespread works of Sir
Ronald Arthur Fisher, the greatest statistician of all time who died
in the 1960's. Just imagine what he could have done with just a
modern pocket calculator, never mind a personal computer.
----
Reg.

radar and health ?
 

In article ,
The Visitor wrote:

Me wrote:
7.6Kw Pulsed Xband Radars have an AVERAGE
Power of less than 20 watts.

I know it works in pulses and it is the pulse you should look out for.
Like a microwave oven , it can induce voltages in pieces of metal, high
enough to cause sparks. What would that do to a person with a pacemaker?

No, absolutly NOT, Microwave Ovens are NOT pusled, they are CW, and
continious. It is AVERAGE Power that fries you, not Peak Pulse Power.
See, this is what you seem not to understand, about the technology that
is being discussed. You don't seem to have a grasp of how the technolgy
works.


I only know the power rating.
I am not sure arcing incidents are that rare as I have met a couple of
people who claim to have seen it happen.

and I have meet a lot of people that claim to have seen and been
kidnapped by aliens, too......

If a hammer drops on your foot and then rests there for 20 minutes, is
it the pulse or the average force to look out for.

not analogous, at all, and just shows that yoiu don't undertand the
technology that you talking about.


My radar...

Peak Power Output: 7.5 KW nominal, 6.0 KW minimum

Output Frequency: 9375 Mhz (X-Band)

Most likely using a 2J42 Magnitron or equivilent....


I think it does 160 pulses per second.

that seems a bit low, should be in the 500 to 750 range, but ok..

and the Pulse Width, which you don't cite, is the determining factor
in calculating the Average Power of the RF Energy emitted from the
device. Typical Pulse Widths would be in the .1 to 1 microsecond range
for this type of radar. So lets take 1 microsecond.
1 * 160 = 160 microseconds total ON time out of 1000000 microsends/second
160.0/1000000 *7500 Watts Peak Pulse Power = 1.2 Watts Average Power

Now understand that RF Energy is nonIonizing radiation and therefore
interacts with biologics as HEAT. Now just how much heat will be
transfered to you from a 1.2 Watt light bulb held in your hand,
assuming that you get 100% capture of that power into your hand,
and considering that if your standing out in front of the antenna
even at one foot, the Inverse Square Law still applies?




You would be willing to take the full brunt of that one foot away? I
will be back at the airport this afternoon and ask for someone to hold
thier head up to the radome. I never went to radar school.

that is obvious....


I'll take your word for it, but I won't volunteer!

Me

radar and health ?
 

Anyone that was involved with the Nike Hercules missile system in the
late Fifties and through the early Seventies was around high powered
pulse radar. It was deployed around major metropolitan areas in the
States and other places around the globe.

All the tracking stuff was short pulse "X" band and maybe a couple
hundred watts average.

But the big stuff was the acquistion or search radar that was "L" band.
The one I worked with in Korea was maybe 5 or 6 megawatts peak and 4 or
5 kw average on the "L" band.

Some Stateside sites had the big G.E. "L" band job that was fairly long
pulse and put out 10 megawatts peak and 18-20 kw average. I was real
pleased that it had a rack mounted Bird wattmeter and I was impressed
to see a solid 18-20 kw average power running through the waveguide to
the antenna.

The range radar was Ku band (15-17 kmc) (TRR to you Nike guys) and one
of the old timers I worked with told me that if you directed the
antenna towards an individual, he would feel the heat. And I'm sure
that's true. We're all familiar with microwave cooking.

John