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LazMan
Premium
join:2003-03-26
canada
reply to DonLibes

Re: how close can a cell tower be to a house?

I'm going to say it's not a micro-cell site; and is more likley a DAS for smart meters, public transport, or some other use...

There's no microwave uplink visable (usually a small "drum" 12-20" across) to link the site to a larger network... Cell repeaters can't operate uplinks across the same antenna sectors used for cell service; nor is it common to feed fibre to a micro-cell site.

As for the safety - I'm a firefighter, a telephone/cellular tech, and have wrenched on and painted race cars for years. I'm getting cancer at some point - there will be no way for me to tell which of my potentially risky exposures, if any, will be responsible... I don't believe there's any great risk from Wifi or cell exposure; but we'll only know for sure in the future, after the technology has been around for 30-40 years...



whizkid3
Premium,MVM
join:2002-02-21
Queens, NY
kudos:9

2 recommendations

said by LazMan:

we'll only know for sure in the future, after the technology has been around for 30-40 years...

People have been using microwaves routinely since WWII, some 70 years. Electromagnetic waves, which includes microwaves, have been around since...hmmm...the big bang.

Unfortunately, the average tin foil hat wearer easily gets electromagnetic waves confused with ionizing radiation - the stuff from nuclear weapons - and panics; not realizing their walls are full of wires giving off electromagnetic waves that are much stronger when they fall upon the body than tiny antennas placed 30 feet high on a pole.


Sell Tower

@151.190.0.x

A laptop with WiFi is a bigger health hazard -- especially if it's sitting on your lap!



pende_tim
Premium
join:2004-01-04
Andover, NJ
kudos:1
Reviews:
·Comcast
reply to LazMan

It is very hard to tell from the picture with all the lower level trees but it does look like there is a fiber run to the pole that does not continue past the pole.

It could be CATV, but the inline can looks suspiciously like a fiber amplifier.
--
The difference between genius and stupidity is that genius has its limits.


cooldude9919

join:2000-05-29
kudos:5

said by pende_tim:

It is very hard to tell from the picture with all the lower level trees but it does look like there is a fiber run to the pole that does not continue past the pole.

It could be CATV, but the inline can looks suspiciously like a fiber amplifier.

Fiber amp?? Pretty sure it is a splice box/container, so yes it is fiber, but not an amp.


LazMan
Premium
join:2003-03-26
canada

1 recommendation

reply to whizkid3

said by whizkid3:

People have been using microwaves routinely since WWII, some 70 years. Electromagnetic waves, which includes microwaves, have been around since...hmmm...the big bang.

True enough - although the plethora of devices has increased dramatically in the last 5 years (WiFi and Cell) - I agree that EM waves are EM waves, and we recieve more from the sun then man-made sources; but only time will tell if we're right - or if we should have busted out the tin-foil hats, too....

Just remember - living is 100% fatal... No one gets out alive... :P


LazMan
Premium
join:2003-03-26
canada
reply to cooldude9919

said by cooldude9919:

said by pende_tim:

It is very hard to tell from the picture with all the lower level trees but it does look like there is a fiber run to the pole that does not continue past the pole.

It could be CATV, but the inline can looks suspiciously like a fiber amplifier.

Fiber amp?? Pretty sure it is a splice box/container, so yes it is fiber, but not an amp.

True, there is a lashback there (and a pretty sloppy one at that) with a splice can, but from this angle, it's impossible to say if it's connected to equipment at the pole, or if it's just coincidental...

cooldude9919

join:2000-05-29
kudos:5

said by LazMan:

said by cooldude9919:

said by pende_tim:

It is very hard to tell from the picture with all the lower level trees but it does look like there is a fiber run to the pole that does not continue past the pole.

It could be CATV, but the inline can looks suspiciously like a fiber amplifier.

Fiber amp?? Pretty sure it is a splice box/container, so yes it is fiber, but not an amp.

True, there is a lashback there (and a pretty sloppy one at that) with a splice can, but from this angle, it's impossible to say if it's connected to equipment at the pole, or if it's just coincidental...

True, it looks like all the cables go up the pole on the back side that we cant see. IMHO with it appearing to be the last pole with nothing past it, unless they have FTTH there, i wouldnt see them running fiber and stopping in a residential area like that for a different reason?


LazMan
Premium
join:2003-03-26
canada

Nothing says it isn't a "dip" - that the aerial structures go underground at that point... Again, no real way to tell from the OP's picture.

Or, the fibre could terminate there, and be feeding that radio equipment... Dunno...


peterboro
Avatars are for posers
Premium
join:2006-11-03
Peterborough, ON
reply to LazMan

said by LazMan:

As for the safety - I'm a firefighter, a telephone/cellular tech, and have wrenched on and painted race cars for years. I'm getting cancer at some point - there will be no way for me to tell which of my potentially risky exposures, if any, will be responsible... I don't believe there's any great risk from Wifi or cell exposure; but we'll only know for sure in the future, after the technology has been around for 30-40 years...

You and I chose to do this stuff over the years but kids in school and living near these towers didn't. My son worked cell towers out west until recently and thankfully decided to go back to school.


LazMan
Premium
join:2003-03-26
canada

said by peterboro:

said by LazMan:

As for the safety - I'm a firefighter, a telephone/cellular tech, and have wrenched on and painted race cars for years. I'm getting cancer at some point

You and I chose to do this stuff over the years but kids in school and living near these towers didn't. My son worked cell towers out west until recently and thankfully decided to go back to school.

I can't argue for, or against, with any great conviction... We (in generally) are getting exposed to more and more of this type of radiation. There's studies that say it's harmless, there's studies that say it's harmful... As I said before, the only true test, will be time.

Studies are generally useless, I hate to say, because it's rare one doesn't start with an end in mind. Data can be manipulated, "events" excluded or included, to fit the overall end goal.

peterboro
Avatars are for posers
Premium
join:2006-11-03
Peterborough, ON

said by LazMan:

I can't argue for, or against, with any great conviction... We (in generally) are getting exposed to more and more of this type of radiation. There's studies that say it's harmless, there's studies that say it's harmful... As I said before, the only true test, will be time.

You and I may not be around to find out. But as long as there is "big money" and a large segment of the population who just have to have all their ridiculous little gadgets connected everywhere the truth will be suppressed as long as possible if history is any indicator.


49528867
Premium
join:2010-04-16
Fort Lauderdale, FL
kudos:3

1 recommendation

reply to whizkid3

said by whizkid3:

Unfortunately, the average tin foil hat wearer easily gets electromagnetic waves confused with ionizing radiation - the stuff from nuclear weapons - and panics;

I would have to respectfully disagree that non-ionizing cannot cause health hazards, I personally, as do many others, including a group within the National Association of Broadcasters, who feel there is a direct connection between certain forms of cancer and long term exposure to RF. This effect is compounded by both the power level of the exposure and the frequency of the RF one is being exposed to, in other words the higher the power levels and or the higher the frequency, the greater the dangers of cellular mutation.

Now the conventional wisdom is RF only causes localized cellular heating, and the effects of any heating reverses itself once the exposure to the RF is eliminated, personally I believe there is more to it but it either has not been scientifically quantified or…

Personally I have known too many broadcast engineers who have had their retirement cut short by leukemia to dismiss it as a coincidence, and while I do not consider myself as a member of the tin-foil hat club, I do everything possible to limit my exposure to RF such as minimizing cell phone use and using the speakerphone feature whenever possible to maximize the distance between me and the handset.

Wayne
--
"It is sobering to reflect that one of the best ways to get yourself a reputation as a dangerous citizen these days is to go about repeating the very phrases which our founding fathers used in the struggle for independence." - Charles A. Beard


cowboyro
Premium
join:2000-10-11
Shelton, CT

said by 49528867:

I would have to respectfully disagree that non-ionizing cannot cause health hazards, I personally, as do many others, including a group within the National Association of Broadcasters, who feel there is a direct connection between certain forms of cancer and long term exposure to RF. This effect is compounded by both the power level of the exposure and the frequency of the RF one is being exposed to, in other words the higher the power levels and or the higher the frequency, the greater the dangers of cellular mutation.

I agree.
Some claim that electrical wires from a house also radiate. True, but there is no comparison to RF. None whatsoever. In fact at any distance significantly higher than the one between the AC conductors (say 1ft), the net field is 0 for all practical purposes as the fields generated by the carrying conductors cancel each other.
There is research made which shows without doubt that living organisms are affected by exposure to RF. Sure no links between cellphones and cancer have been made yet, but cellphones have only been used extensively for some 10 years. Asbestos doesn't give cancer instantly either, it may take 20-40 years...


AVD
Respice, Adspice, Prospice
Premium
join:2003-02-06
Onion, NJ
kudos:1

said by cowboyro:

I agree.
Some claim that electrical wires from a house also radiate. True, but there is no comparison to RF.

Any wire that carries AC current creates RF. Shielded cable might shield it, but all conductors with an electric current that changes emit EM radiation.
--
--Standard disclaimers apply.--
google this "(sqrt(cos(x))*cos(200*x)+sqrt(abs(x))-0.7)*(4-x*x)^0.01, sqrt(9-x^2), -sqrt(9-x^2)"


cowboyro
Premium
join:2000-10-11
Shelton, CT

said by AVD:

Any wire that carries AC current creates RF. Shielded cable might shield it, but all conductors with an electric current that changes emit EM radiation.

Only the amount is insignificant since:
1 - the length of the circuit is insignificant compared to the wavelength
2 - there are 2 conductors carrying current in opposing directions effectively canceling the field.

For all practical purposes the field generated is 0.


AVD
Respice, Adspice, Prospice
Premium
join:2003-02-06
Onion, NJ
kudos:1

said by cowboyro:

[
2 - there are 2 conductors carrying current in opposing directions effectively canceling the field.

I don't think it works like that.
--
--Standard disclaimers apply.--
google this "(sqrt(cos(x))*cos(200*x)+sqrt(abs(x))-0.7)*(4-x*x)^0.01, sqrt(9-x^2), -sqrt(9-x^2)"


fifty nine

join:2002-09-25
Sussex, NJ
kudos:2
reply to cowboyro

said by cowboyro:

said by AVD:

Any wire that carries AC current creates RF. Shielded cable might shield it, but all conductors with an electric current that changes emit EM radiation.

Only the amount is insignificant since:
1 - the length of the circuit is insignificant compared to the wavelength
2 - there are 2 conductors carrying current in opposing directions effectively canceling the field.

For all practical purposes the field generated is 0.

Take the input to any audio amplifier, and attach a small piece of wire or even your finger and touch it.

The 'hummmmmmm' you hear is radiation from the AC powerline.


cowboyro
Premium
join:2000-10-11
Shelton, CT
reply to AVD

said by AVD:

said by cowboyro:

[
2 - there are 2 conductors carrying current in opposing directions effectively canceling the field.

I don't think it works like that.

What you "think" doesn't matter as it's wrong.


cowboyro
Premium
join:2000-10-11
Shelton, CT
reply to fifty nine

said by fifty nine:

Take the input to any audio amplifier, and attach a small piece of wire or even your finger and touch it.

The 'hummmmmmm' you hear is radiation from the AC powerline.

It's capacitive coupling. Not to be confused with electromagnetic radiation.
If you unplug all loads from a house the measured active power is pretty much the amount of power radiated. Zero.
If any significant amount of energy would be radiated then a GFI would trip instantly.


49528867
Premium
join:2010-04-16
Fort Lauderdale, FL
kudos:3
reply to AVD

said by AVD:

said by cowboyro:

[2 - there are 2 conductors carrying current in opposing directions effectively canceling the field.

I don't think it works like that.

You might not think it does, but the reality of it is, cowboyro is quite correct.

The primary factor required in order to generate a decent amount of a radiated signal, canceling excluded, is one needs a radiator tuned to the to the frequency to be radiated, which for a 60Hz quarter wave antenna is roughly 4 million feet, and unless you are dealing with a rather large structure I am willing to bet that is probably not going to be found in a straight run.

Wayne
--
"It is sobering to reflect that one of the best ways to get yourself a reputation as a dangerous citizen these days is to go about repeating the very phrases which our founding fathers used in the struggle for independence." - Charles A. Beard


AVD
Respice, Adspice, Prospice
Premium
join:2003-02-06
Onion, NJ
kudos:1

I'm talking about how a circuit cancels each other out.

and yet my AM radio picks up 60hz hums all the time.



aannoonn

@optonline.net
reply to AVD

said by AVD:

said by cowboyro:

Some claim that electrical wires from a house also radiate. True, but there is no comparison to RF.

Any wire that carries AC current creates RF. Shielded cable might shield it, but all conductors with an electric current that changes emit EM radiation.

You don't get "RF" from a 60 Hz wire. 60 Hz is not RF. RF is defined as starting at 3 kHz.

For any frequency (even DC), the electric field is proportional to the voltage. The magnetic field is proportional to the current. So you get an electric field from house wiring even if everything is unplugged and there is no current flowing.


cowboyro
Premium
join:2000-10-11
Shelton, CT
reply to AVD

said by AVD:

I'm talking about how a circuit cancels each other out.

and yet my AM radio picks up 60hz hums all the time.

The AM radio is capable of picking up signals well below 1uV/m
An AM radio is also capable of picking a noise from a common electronic wrist watch.


whizkid3
Premium,MVM
join:2002-02-21
Queens, NY
kudos:9

4 recommendations

reply to 49528867

said by 49528867:

I would have to respectfully disagree that non-ionizing cannot cause health hazards...

I didn't say EMF (electro-magnetic fields) doesn't cause health hazards. Obviously standing in front of a radar antenna or putting your hand in a running microwave oven is sure to mess one up. However, there have been countless studies; and decades and decades of statistical data that has been reviewed, with the collective conclusion that aside from being burnt from over-exposure to strong fields; EMF is not hazardous to our health. There have been some studies that have possibly shown a slightly higher incidence; etc. In all of those cases the studies turned out to be biased, or improper conclusions drawn. (This is not me ad-libbing. This is the general conclusion from the medical research community. Obviously, those whose research was concluded to be fault or biased, may disagree.)

said by 49528867:

I [and a group in the NAB] personally feel there is a direct connection between certain forms of cancer and long term exposure to RF.

I respect your feelings. And those of some people in the NAB. And anyone else's feelings. However, collectively, this adds up to absolutely zero level of scientific evidence.

said by 49528867:

[I believe] This effect is compounded by both the power level of the exposure and the frequency of the RF one is being exposed to, in other words the higher the power levels and or the higher the frequency, the greater the dangers of cellular mutation. Personally I believe there is more to it.

More feelings and personal beliefs - not facts. Cellular [genetic] mutation has never been demonstrated from EMF well up beyond milli-meter wave frequencies. Ever. That's why its called non-ionizing radiation. X-rays? Yes. Gamma rays? Yes. Hiroshima? Yes. But that's not what we're talking about.

said by 49528867:

Now the conventional wisdom is RF only causes localized cellular heating, and the effects of any heating reverses itself once the exposure to the RF is eliminated...

Well, for the record then; lets be clear here. At the molecular level, RF doesn't cause heat. It adds energy to the electrons in atoms; similarly to the photo-electric effect. The electrons bounce around; hit each other; and the result is that the energy dissipates as heat. This is why one's Swanson's dinner is still cooking after it comes out of the microwave oven. For genetic mutation to occur; the atoms themselves have to actually change. This does not happen by adding energy (or even losing & gaining) electrons (all of which occurs normally all of the time in the human body - electric currents.) This is borne out both by the laws of physics; and countless studies. There would be reams of evidence of statistical data available, if EMF actually caused mutations.

Think about cell-phone penetration. There have been no tremendous increases in diseases from genetic mutation - cancers - that is in any way attributable to an increase in cell phone use; certainly not more than what can be attributed to statistical aberation in isolated circumstances. No one has been able to show any correlation at all; which would be necessary well before cause and effect could be established. If indeed, EMF was responsible for leukemia, brain cancer, big-toe cancer, etc. - it would have long ago been clearly discerned. And it would not have needed a scientific study. The incidence of these cancers would be skyrocketing around the world.

Likewise, there haven't been any incidence of going in for an MRI, where one's body is subjected to tremendously strong electro-magnetic fields; of people developing cancer from this. Actually, the MRI has turned out to be a cancer saving miracle.

said by 49528867:

Personally I have known too many broadcast engineers who have had their retirement cut short by leukemia to dismiss it as a coincidence.

Thanks, Wayne. I do appreciate your points. Bear in mind, however, when it comes to science & statistics, the level of people you are talking about don't even rise to anything other than a miniscule isolated sampling pool that doesn't arise to any blip on the radar. Sorry to hear about it. In 2000, approximately 256,000 children and adults around the world developed some form of leukemia, and 209,000 died from it. (Source - Wikipedia) That is 6.4 thousandths of a percent. Certainly, if EMF were responsible, common sense alone would say those numbers have to be higher.

There have been a huge swath of studies in the interest of seeing if there is any link between leukemia and any form of EMF going back over 30 years. The only statistical evidence that even came close to correlating to something worth looking into very deeply, was a possible relationship between Extremely Low-Frequency (ELF) Electro-magnetic fields and incidences of childhood leukemia. The conclusions, after 30 years of study, are as follows:

International Agency for Research on Cancer:
»monographs.iarc.fr/ENG/Monograph···ndex.php

quote:
There is limited evidence that high levels of ELF magnetic (but not electric) fields might cause childhood leukemia. Exposure to significant ELF magnetic fields might result in twofold excess risk for leukemia for children exposed to these high levels of magnetic fields. However, the report also says that methodological weaknesses and biases in these studies have likely caused the risk to be overstated. No evidence for a relationship to leukemia or another form of malignancy in adults has been demonstrated.
Note that when the IARC says "possibly carcinogenic to humans"; this classification is used to denote an agent for which there is limited evidence of carcinogenicity in humans and less than sufficient evidence for carcinogenicity in experimental animals (other examples that are "possibly carcinogenic to humans include drinking coffee and welding fumes. There are countless others. Maybe the IAB guys just drank a lot of coffee?

World Health Organization:
»www.who.int/mediacentre/factshee···dex.html

The WHO concluded, that even if ELF exposure were later discovered to actually cause childhood leukemia, it would account for just 100 to 2400 cases worldwide each year, representing 0.2 to 4.9% of the total incidence of childhood leukemia for that year (about 0.03 to 0.9% of all leukemias). Note that taking the worst case, those numbers would account for an incidence rate of less than one-millionth of one percent. That's a long shot in comparison of one's odds of getting struck by lightning or dying in an airplane crash. Certainly, we have much, much more to live in fear about.

Note that the FCC, and IEEE, requirements, limit exposure to RF EMF by virtue of the distance that such radiators must be placed from buildings (for example). The fields from the antennas in the photo are well below any strength even rising to concern. Rumors, old-brodcaster's tales, etc - it just has not been borne out by any type of scientific facts. A lot of this started in the 1970s, when big bad three-mile island released some gawd awful radiation that decimated the population. Since then, anything to do with the word 'radiation', has become a magic enemy to be avoided. Whether consciously or subconsciously, many people harbor concerns regarding EMF from this period. Fortunately, there is nothing to be concerned about except being over-fearful. That same goes for all those people dying from sitting too close to the television; or all those people dying from having microwave ovens in their homes. No facts to back it up. None.



fifty nine

join:2002-09-25
Sussex, NJ
kudos:2

1 recommendation

reply to cowboyro

said by cowboyro:

It's capacitive coupling. Not to be confused with electromagnetic radiation.

Wait, what?

It's the same thing.


aurgathor

join:2002-12-01
Lynnwood, WA
kudos:1

said by fifty nine:

said by cowboyro:

It's capacitive coupling. Not to be confused with electromagnetic radiation.

Wait, what?

It's the same thing.

Nope. Capacitive coupling and RF pickup are 2 very different things. Capaqcitive coupling works only over relatively short distances while RF pickup, as long you have a powerful enough transmitter and a sensitive enough receiver, can work over very-very long distances.
--
Wacky Races 2012!
Expand your moderator at work


whizkid3
Premium,MVM
join:2002-02-21
Queens, NY
kudos:9

2 recommendations

reply to aurgathor

Re: how close can a cell tower be to a house?

said by aurgathor:

said by fifty nine:

said by cowboyro:

It's capacitive coupling. Not to be confused with electromagnetic radiation.

Wait, what? It's the same thing.

Nope. Capacitive coupling and RF pickup are 2 very different things.

The actions of any capacitor work because of an electromagnetic field. Nothing more, nothing less. Radio waves are also due to electromagnetic fields.
See: Electromagnetic fields, Maxwell's equations.
The only difference between the two is that at a capacitor the near-field equations apply & the 'electric' portion of the field is stronger. It is still an EMF based on moving electric charges and does indeed radiate. Unless its part of resonant circuit, its not very useful as a transmitter.
quote:
In the past, electrically charged objects were thought to produce two different, unrelated types of field associated with their charge property. An electric field is produced when the charge is stationary with respect to an observer measuring the properties of the charge, and a magnetic field (as well as an electric field) is produced when the charge moves (creating an electric current) with respect to this observer. Over time, it was realized that the electric and magnetic fields are better thought of as two parts of a greater whole — the electromagnetic field.

if either the electric or magnetic field has a time-dependence, then both fields must be considered together as a coupled electromagnetic field using Maxwell's equations. A changing electromagnetic field which is physically close to currents and charges (see near and far field for a definition of “close”) will have a dipole characteristic that is dominated by either a changing electric dipole, or a changing magnetic dipole. This type of dipole field near sources is called an electromagnetic near-field.


cowboyro
Premium
join:2000-10-11
Shelton, CT

said by whizkid3:

It is still an EMF based on moving electric charges and does indeed radiate. Unless its part of resonant circuit, its not very useful as a transmitter.

Which in turn means that the amount of energy radiated is negligible.