2.4GHz WDSL antenna radiation hazard

[Mark Harris]

Please excuse me if this is not exactly the right group to inquire
about this, but it seems like there is alot of experience here.

My boss recently installed a WDSL antenna on the roof above my
workstation. It is the 2.4GHz frequency hoping spread spectrum (FHSS)
type. Since the repeater is about 4KM away, line-of-sight, I assume
the output is less than a watt.

It has a rectangular open lattice reflector (parabolic), about a half
metre square, with the transmitter bulb protruding out from the
center. It is on top of a 6' vertical steel pole, placing it about
8-9' above my head.

I am seated just below it, but several metres behind the
line-of-sight, under a corrugated steel roof.

I understand it is probably highly directional. However, I am still
concerned about ongoing exposure, and have read conflicting opinions
about dosages at this level. Apparently, 2.4GHz has bioactive
properties.

Would I be receiving any appreciable amount of microwave radaition
from this antenna?

Does the metal roof serve as a protective shield to any degree?

Could someone venture an estimate as to the dosage given a 1W output?

Thank you very much for any assistance.

Mark Harris

 

[Mac]

On Sat, 11 Jun 2005 13:55:49 +0930, Mark Harris wrote:

Please excuse me if this is not exactly the right group to inquire
about this, but it seems like there is alot of experience here.

My boss recently installed a WDSL antenna on the roof above my
workstation. It is the 2.4GHz frequency hoping spread spectrum (FHSS)
type. Since the repeater is about 4KM away, line-of-sight, I assume
the output is less than a watt.

It has a rectangular open lattice reflector (parabolic), about a half
metre square, with the transmitter bulb protruding out from the
center. It is on top of a 6' vertical steel pole, placing it about
8-9' above my head.

I am seated just below it, but several metres behind the
line-of-sight, under a corrugated steel roof.

I understand it is probably highly directional. However, I am still
concerned about ongoing exposure, and have read conflicting opinions
about dosages at this level. Apparently, 2.4GHz has bioactive
properties.

Would I be receiving any appreciable amount of microwave radaition
from this antenna?

Does the metal roof serve as a protective shield to any degree?

Yes. Big time. It reflects the radiation away.

Could someone venture an estimate as to the dosage given a 1W output?

Thank you very much for any assistance.

Mark Harris

If the metal roof is between you and the antenna, and the radiated
power is only 1 Watt, and you are several meters away from the radiator,
and the parabolic dish is directing the radiation AWAY from you I would
almost say don't worry about it. Between the parabolic reflector and
the roof, the vast majority of the radiated power will be directed away
from you.

--Mac

 

[rex]

On Sat, 11 Jun 2005 13:55:49 +0930, Mark Harris
<markharris@counterkey.com> wrote:

Please excuse me if this is not exactly the right group to inquire
about this, but it seems like there is alot of experience here.

My boss recently installed a WDSL antenna on the roof above my
workstation. It is the 2.4GHz frequency hoping spread spectrum (FHSS)
type. Since the repeater is about 4KM away, line-of-sight, I assume
the output is less than a watt.

It has a rectangular open lattice reflector (parabolic), about a half
metre square, with the transmitter bulb protruding out from the
center. It is on top of a 6' vertical steel pole, placing it about
8-9' above my head.

I am seated just below it, but several metres behind the
line-of-sight, under a corrugated steel roof.

I understand it is probably highly directional. However, I am still
concerned about ongoing exposure, and have read conflicting opinions
about dosages at this level. Apparently, 2.4GHz has bioactive
properties.

Would I be receiving any appreciable amount of microwave radaition
from this antenna?

Very unlikely.

Does the metal roof serve as a protective shield to any degree?

Yes. Probably a very large degree. Way better than a tin-foil hat.

Could someone venture an estimate as to the dosage given a 1W output?

You said earlier, "I assume the output is less than a watt." But I would
venture that through a steel roof off the edge of the dish, either way
-- I wouldn't worry.

Thank you very much for any assistance.

If you live in the United States, what your boss is doing is probably
illegal. You could try narc'ing him/her to the FCC. Whether they would
care enough to even get involved is another question. If they did, it
would not be because you are getting irradiated, but rather because this
would exceed ERP broadcast power for an unlicensed station.

Mark Harris

 

[Roger Lascelles]

"Mark Harris" <markharris@counterkey.com> wrote in message
news:fvoka1dko0gpl59s29v3hkrui7dmu9hg1j@4ax.com...

Please excuse me if this is not exactly the right group to inquire
about this, but it seems like there is alot of experience here.

My boss recently installed a WDSL antenna on the roof above my
workstation. It is the 2.4GHz frequency hoping spread spectrum (FHSS)
type. Since the repeater is about 4KM away, line-of-sight, I assume
the output is less than a watt.

It has a rectangular open lattice reflector (parabolic), about a half
metre square, with the transmitter bulb protruding out from the
center. It is on top of a 6' vertical steel pole, placing it about
8-9' above my head.

I am seated just below it, but several metres behind the
line-of-sight, under a corrugated steel roof.

I understand it is probably highly directional. However, I am still
concerned about ongoing exposure, and have read conflicting opinions
about dosages at this level. Apparently, 2.4GHz has bioactive
properties.

Would I be receiving any appreciable amount of microwave radaition
from this antenna?

Does the metal roof serve as a protective shield to any degree?

Could someone venture an estimate as to the dosage given a 1W output?

Thank you very much for any assistance.

Mark Harris

If the metal roof is completely blocking the path between you and the
antenna, and there is no other metal object which can reflect the beam onto
you by some other path, then you really are extremely safe. I would gues
that your body receives a fantastically minute amount of the total radiated
power. I would be happy to work under the same conditions, and I am a very
careful person.

I have worked with microwaves, and I noticed that at 10GHz, even 0.01 watt
continuously radiated from a horn antenna 4 metres away is enough to give a
"microwave headache". You can actually feel it on your hand if you put your
hand in front of a horn antenna at 0.01 watt.

Roger

 

[Frank Bemelman]

"Mark Harris" <markharris@counterkey.com> schreef in bericht
news:fvoka1dko0gpl59s29v3hkrui7dmu9hg1j@4ax.com...

[snip]

Now that smoking is practically banned, complainers have
found a new target -> radiation.

--
Thanks, Frank.
(remove 'q' and 'invalid' when replying by email)

 

Mark Harris <markharris@counterkey.com> wrote:

Please excuse me if this is not exactly the right group to inquire
about this, but it seems like there is alot of experience here.

My boss recently installed a WDSL antenna on the roof above my
workstation. It is the 2.4GHz frequency hoping spread spectrum (FHSS)
type. Since the repeater is about 4KM away, line-of-sight, I assume
the output is less than a watt.

It has a rectangular open lattice reflector (parabolic), about a half
metre square, with the transmitter bulb protruding out from the
center. It is on top of a 6' vertical steel pole, placing it about
8-9' above my head.

I am seated just below it, but several metres behind the
line-of-sight, under a corrugated steel roof.

I understand it is probably highly directional. However, I am still
concerned about ongoing exposure, and have read conflicting opinions
about dosages at this level. Apparently, 2.4GHz has bioactive
properties.

Would I be receiving any appreciable amount of microwave radaition
from this antenna?

With the corrugated roof, maybe you should worry more about any possible
antenna directed towards you. (esp the one at 4 km?)

There are ofcourse magnetic fields involved too, but those are likely to be
infinite small.

 

[doug dwyer]

The threshold for danger will be if you can hear the clicking in your
head due to the instantaneous microwave heating of your brain.and the
resultant fluid shock wave reaching the innear ear.

In message <1118476256.eca52c38f0a9861f899039c2d491a286@teranews>, Roger
Lascelles <despam_rklasl@aanet.com.au> writes

"Mark Harris" <markharris@counterkey.com> wrote in message
news:fvoka1dko0gpl59s29v3hkrui7dmu9hg1j@4ax.com...
Please excuse me if this is not exactly the right group to inquire
about this, but it seems like there is alot of experience here.

My boss recently installed a WDSL antenna on the roof above my
workstation. It is the 2.4GHz frequency hoping spread spectrum (FHSS)
type. Since the repeater is about 4KM away, line-of-sight, I assume
the output is less than a watt.

It has a rectangular open lattice reflector (parabolic), about a half
metre square, with the transmitter bulb protruding out from the
center. It is on top of a 6' vertical steel pole, placing it about
8-9' above my head.

I am seated just below it, but several metres behind the
line-of-sight, under a corrugated steel roof.

I understand it is probably highly directional. However, I am still
concerned about ongoing exposure, and have read conflicting opinions
about dosages at this level. Apparently, 2.4GHz has bioactive
properties.

Would I be receiving any appreciable amount of microwave radaition
from this antenna?

Does the metal roof serve as a protective shield to any degree?

Could someone venture an estimate as to the dosage given a 1W output?

Thank you very much for any assistance.

Mark Harris

If the metal roof is completely blocking the path between you and the
antenna, and there is no other metal object which can reflect the beam onto
you by some other path, then you really are extremely safe. I would gues
that your body receives a fantastically minute amount of the total radiated
power. I would be happy to work under the same conditions, and I am a very
careful person.

I have worked with microwaves, and I noticed that at 10GHz, even 0.01 watt
continuously radiated from a horn antenna 4 metres away is enough to give a
"microwave headache". You can actually feel it on your hand if you put your
hand in front of a horn antenna at 0.01 watt.

Roger

--
dd

 

[Rich Grise]

On Sat, 11 Jun 2005 13:55:49 +0930, Mark Harris wrote:

Please excuse me if this is not exactly the right group to inquire
about this, but it seems like there is alot of experience here.

Probably over a thousand years, cumulatively. Thank you very much.
....

the output is less than a watt.
....
8-9' above my head.
....
I am seated just below it, but several metres behind the
line-of-sight, under a corrugated steel roof.
....
about dosages at this level. Apparently, 2.4GHz has bioactive
properties.
....

Yeah - if you were inside a 600 watt microwave oven, your blood
would boil.

Would I be receiving any appreciable amount of microwave radaition
from this antenna?

Not from _that_ one.

Does the metal roof serve as a protective shield to any degree?

Yes, but it's irrelevant.

Could someone venture an estimate as to the dosage given a 1W output?

Negligible.

Thank you very much for any assistance.

If you're really that paranoid, maybe this link could help:
http://zapatopi.net/afdb.html ;-)

Cheers!
Rich

 

[Rich The Newsgroup Wacko]

On Sat, 11 Jun 2005 17:50:58 +1000, Roger Lascelles wrote:

"Mark Harris" <markharris@counterkey.com> wrote in message
....
Would I be receiving any appreciable amount of microwave radaition
from this antenna?
....
I have worked with microwaves, and I noticed that at 10GHz, even 0.01
watt continuously radiated from a horn antenna 4 metres away is enough
to give a "microwave headache". You can actually feel it on your hand
if you put your hand in front of a horn antenna at 0.01 watt.

Yeah, if you have hypersensitivity disorder.

Geez, when I was in the USAF, working with jammer transmitters, (whose
frequency is, of course, classified information), some guy showed me
how the little blade antennas could light up that NE-2 screwdriver thingie,
but if you didn't have the little NE-2 screwdriver thingie handy, you
could feel it with your hand. It feels warm. This is at mumble-mumble
watts (classified information, but a couple of orders of magnitude, at
least, greater than zero point zero one watts. Sheesh!)

And it hasn't affected my brain at all. No, not even a little bit. Not
at all. NO EFFECT, I TELL YOU!!!!
--
Cheers!
Rich
P.S.: ;-D
------
"The wages of sin are high -- unless you know someone who does it for
nothing."

 

[Richard the Dreaded Liber]

On Sat, 11 Jun 2005 10:25:21 +0200, Frank Bemelman wrote:

"Mark Harris" <markharris@counterkey.com> schreef in bericht
news:fvoka1dko0gpl59s29v3hkrui7dmu9hg1j@4ax.com...
[snip]
Now that smoking is practically banned, complainers have
found a new target -> radiation.

Anybody got a link to that stock footage of that H-bomb test
that shot ocean water five miles high and the battleships look
like ants?

I just saw a rerun of it recently in the opening credits of the
ST:E ep where they were doing the Earth Empire alternate universe.
(I was a little disappointed with the story until the second rerun
where I finally realized, "Oh! _Empress_ _Sato_! [Heh, heh, heh!]")

Thanks,
Rich

 

[Apostrophe Police]

On Sat, 11 Jun 2005 10:19:59 +0000, pbdelete wrote:

There are ofcourse magnetic fields involved too, but those are likely to
be infinite small.
^^^^^^^^

Infinitesimally.
--
Rich Grise, Self-Appointed Chief,
Apostrophe Police
;-P

 

[Jim Thompson]

On Sat, 11 Jun 2005 13:55:49 +0930, Mark Harris
<markharris@counterkey.com> wrote:

[snip]

My boss recently installed a WDSL antenna on the roof above my
workstation. It is the 2.4GHz frequency hoping spread spectrum (FHSS)
type. Since the repeater is about 4KM away, line-of-sight, I assume
the output is less than a watt.

[snip]

Would I be receiving any appreciable amount of microwave radaition
from this antenna?

[snip]

If you wish to sire children I'd recommend a lead jock strap.

And maybe a hard hat as well.

...Jim Thompson
--
| James E.Thompson, P.E. | mens |
| Analog Innovations, Inc. | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| Phoenix, Arizona Voice480)460-2350 | |
| E-mail Address at Website Fax480)460-2142 | Brass Rat |
| http://www.analog-innovations.com | 1962 |

I love to cook with wine. Sometimes I even put it in the food.

 

[Pete]

Jim Thompson wrote:

And maybe a hard hat as well.

I *hate* to add to these things, but wouldn't a head-piece fashioned
from aluminium foil work better?

Peter

 

[Mark Zenier]

In article <r9vka1lk6k0gi1mqdnk83msr8b38v8ej39@4ax.com>,
rex <notat@hotmail.invalid> wrote:

If you live in the United States, what your boss is doing is probably
illegal. You could try narc'ing him/her to the FCC. Whether they would
care enough to even get involved is another question. If they did, it
would not be because you are getting irradiated, but rather because this
would exceed ERP broadcast power for an unlicensed station.

No, the ERP limit of a spread spectrum part 15 transmitter (47 CFR 15.247)
is 1 watt.

Mark Zenier mzenier@eskimo.com Washington State resident

 

[doug dwyer]

In message <pan.2005.06.11.15.21.15.571940@example.com>, Rich The
Newsgroup Wacko <wacko@example.com> writes

Geez, when I was in the USAF, working with jammer transmitters, (whose
frequency is, of course, classified information), some guy showed me
how the little blade antennas could light up that NE-2 screwdriver
thingie, but if you didn't have the little NE-2 screwdriver thingie
handy, you could feel it with your hand. It feels warm. This is at
mumble-mumble watts (classified information, but a couple of orders of
magnitude, at least, greater than zero point zero one watts. Sheesh!)

And it hasn't affected my brain at all. No, not even a little bit. Not
at all. NO EFFECT, I TELL YOU!!!!
Age 6 at Farnborough Air Show (any one care to guess when this was?) I

was encouraged to stand infront of a meteor nose cone radar with a
fluorescent . I recall its bright light in daylight.
Initiated my interest in electronics but did not interfere with my
initiation of 4 kids.


--
dd

 

[Ben Bradley]

On Sun, 12 Jun 2005 21:58:26 +1000, Pete <pjetson@yahoo.com> wrote:

Jim Thompson wrote:

And maybe a hard hat as well.

I *hate* to add to these things, but wouldn't a head-piece fashioned
from aluminium foil work better?

I'd go for an aluminum foil codpiece, even though some may find it
offensive or disgusting...

http://sorta.stamen.com/mp3s/GeneSimmonsNPR.mp3

Peter

-----
http://mindspring.com/~benbradley

 

[rex]

On Tue, 14 Jun 2005 04:27:35 GMT, Ben Bradley
<ben_nospam_bradley@frontiernet.net> wrote:

I'd go for an aluminum foil codpiece, even though some may find it
offensive or disgusting...

Is this somehow related to Michael Jackson being aquitted? Seems like
something he might wear.

 

[Anonymous Coward]

Mark Harris wrote:

Please excuse me if this is not exactly the right group to inquire
about this, but it seems like there is alot of experience here.

My boss recently installed a WDSL antenna on the roof above my
workstation. It is the 2.4GHz frequency hoping spread spectrum (FHSS)
type. Since the repeater is about 4KM away, line-of-sight, I assume
the output is less than a watt.

It has a rectangular open lattice reflector (parabolic), about a half
metre square, with the transmitter bulb protruding out from the
center. It is on top of a 6' vertical steel pole, placing it about
8-9' above my head.

I am seated just below it, but several metres behind the
line-of-sight, under a corrugated steel roof.

I understand it is probably highly directional. However, I am still
concerned about ongoing exposure, and have read conflicting opinions
about dosages at this level. Apparently, 2.4GHz has bioactive
properties.

Would I be receiving any appreciable amount of microwave radaition
from this antenna?

Does the metal roof serve as a protective shield to any degree?

Could someone venture an estimate as to the dosage given a 1W output?

Thank you very much for any assistance.

Mark Harris

Mark,
Do you own a cell phone? THAT is what you should be worrying about,
if one were to worry about such things. 1000's and probably millions of times
more intense RF radiation field, even if you consider the occasional use issue.
Worry about the chemicals in the water you drink, how much you drink, as in
alcohol, the crap VOC's coming out of the carpet in your house and at work,
1st or 2nd hand smoke, and buckle your seat belt.

Steve

 

[Adrian Tuddenham]

Anonymous Coward <coward@bitbucket.com> wrote:

Do you own a cell phone? THAT is what you should be worrying about,
if one were to worry about such things. 1000's and probably millions of times
more intense RF radiation field, even if you consider the
occasional use issue.
Worry about the chemicals in the water you drink, how much you drink, as in
alcohol, the crap VOC's coming out of the carpet in your house and at work,
1st or 2nd hand smoke, and buckle your seat belt.

....and the effects of perfume in just about everything you buy ...and
other people inflicting their perfumes on you in public places. (Have
you seen the list of chemicals and what their hazards are?)

--
~ Adrian Tuddenham ~
(Remove the ".invalid"s and add ".co.uk" to reply)
www.poppyrecords.co.uk