Question:
: You are, however, right to say that anything : said here about X-rays applies to : RF also. I’d disagree about there being a debate : amongst scientists over this : though – the position I’ve described above : would be generally accepted amongst : physicists. Sorry, but this is incorrect. There is a sharp distinction between both the properties and health hazards assosiated with ionizing and non-ionizing electromagnetic radiation. There is a clear, not vague, distinction between these two major classifations of electromagnetic radiation. Ionizing radiation begins at the short-wavelength ultra violet, and extends as wavelength decreases (and quanta energy correspondingly increases) through the region of the X-ray and gamma ray spectrum. Ionizing radiation is clearly capable of not only atomic ionization, but molecular disruption, with a disruptive effect proportional to dosage on any biological organism unfortunate enough to receive it. (This is why short wavelength ultra-violet kill germs, and why x-rays and gamma rays at high doses can cause radiation poisoning and cancer.) Longer wavelength (lower quanta energy) electromagnetic radiation (power line radiation, radio waves, microwaves) totally lack ionization producing capability, with their only known effect on biological organisms being the production of localized heating effects. Lumping the two categories together is equavalent to saying that vinegar and concentrated sulfuric acid have the same effects, since they’re both acids! Harry C.
Response:
> You are, however, right to say that anything said here about X-rays applies to >RF also. I’d disagree about there being a debate amongst scientists over this >though – the position I’ve described above would be generally accepted amongst >physicists.
There is one important difference between rf and x-rays. That is that x-rays have sufficient energy to knock electrons out of atoms and break chemical bonds. THis is why they are called "ionising radiation". This process is very damaging to living organisms and is the reason why x-rays can induce various types of cancer (in sufficient dose). Radio frequency radiation does not have enough energy to break bonds and the only convincingly demonstrated damage mechanism is through heating. John Walliker
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: Now xrays are really particles, so : they’re not directly relevant, however, the higher in frequency you go, the : higher energy the resulting field (or whatever) has. Actually, energy of ALL wavelenghts exhibits properties of BOTH waves and particles. As the wavelength decreases, the particle theory is a better way to explain its properties. : The higher the energy, : the more likely you’ll begin to see cancer, chromosome damage, etc. regardless : of whether water resonates at a given frequency. Correct.
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- Hide quoted text — Show quoted text -> Also, apparently the wife of the inventor of modern x-ray > photography died early from cancer since she was her husband’s primary guinea > pig for his photography experiments. Now xrays are really particles, so > Whoa whoa!, stop the bus! X-rays are particles? I thought X-rays are RF > energy at a given frequency. So if X-rays are particles, is light a > particle, and microwaves, and radio waves? Yes there is debate amoug > scientists on wether RF radiation is a wave propagating through space or > particles moving through space, but you seem to have taken both positions. > So what is light, particle or wave?
Off-topic, but the answer is "both" or "neither". "Particle" and "wave" are mathematical concepts we use to describe the world around us. Each is a set of attributes. Now, it turns out that some of the observed properties of X-rays (and rf photons, electrons, protons, etc) appear consistent with the behaviour of this abstract concept we call a "particle", others with the other abstract concept we call a "wave". To that extent you can say that an X-ray (or any other photon) "is" a "particle" or a "wave". It doesn’t mean much to argue about which it *really* is though, ‘cos the answer is it’s neither – "wave" and "particle" are just concepts we use to describe it in different contexts. Insisting that it must be one or the other is insisting that ideas we use to describe the world on a human scale (approx. 1m) must be capable of providing, without modification, a complete description of the world on a sub-atomic scale (<10^-10m) – not somthing I’m accusing you of, but there will be someone out there who takes this position. You are, however, right to say that anything said here about X-rays applies to RF also. I’d disagree about there being a debate amongst scientists over this though – the position I’ve described above would be generally accepted amongst physicists. None of this, of course, has any relevance to the subject of this thread! Alan
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I had to respond to this, since there are so many good things to pick on… > I missed the beginning of this thread…. There seem to be two issues: > 1) someone’s pager doesn’t work in close proximity to a transmitter site > 2) someone is concerned about the health issues of being near a transmitter > site. >> The improper operation can be caused by a number of factors…. >> It is also possible (and probably more likely) that your pager cannot >> reject unwanted signals well enough.
-snip- – Hide quoted text — Show quoted text -> AS for safety near a transmitter. There are several points that should be > considered in a rational discussion. Points that have not been made, yet. > 1) Radiated power, dissipates in proportion to the square of the distance. ie, > if you move twice as far away, you get one fourth the power. 10 times farther, > 100 times less power, etc. I’d rather be 50 feet from a 200 watt transmitter > than 2 inches from a 2 watt transmitter any day. > 2) Grounded metal plates completely block RF energy. Most transmitter antennas > are monopoles. This means that they require a ground plane beneath them to > work efficiently (like your car cellular antenna… it works best if mounted > in the CENTER of your metal roof). Underneath the metal plate, there is > essentially NO RF field except to the extent that the metal plate isn’t ‘good’ > enough for the frequency/power of the transmitter.
On what data do you base this statement on? A ground plane antenna doesn’t need a full metal plate below it. In fact, I have yet to see a ground plane antenna where this has been done intentionally. Ground plane antennas do use ground radials which can be simple pieces of wire at a certain length, but a ground ‘plate’ is not required. In addition, the ground radials in a ground plane antenna don’t provide you, standing under the antenna, any protection. Would it suprise you to know that your car chassis itself is radiating energy too. Also what does your statement have to say about glass mount antennas? That they are inefficient? I don’t think so. > 3) All monopole and dipole antennas (working in their designed frequency band) > have a null directly below and above them. A dipole has a torroidal (ie donut) > shaped RF field. If you stand directly below the antenna (with no near field > reflectors), there is NO RF energy from that antenna.
It sounds like you’ve been looking at the pictures in those antenna books and not reading the text. As an engineer, you’re dangerous. The torroidal radiation pattern shows the line at given power level, not the absolute limit for the radiation. There most certainly is radiation below the antenna. If you were to sit below a paging service transmitter with a scanner, you would probably recieve enough power to cause problems no matter where you tune your scanner. Sure, mathmatically there is a null in radiation at certain nodes, but in reality, there are too many other things affecting where the radiation ends up. > In other words, I’d rather live UNDER a transmitter than next door to one! > (note that horizontal power line VLF fields radiate TO the ground, so that max > field strength is directly underneath them)
Dont forget above and to the sides. – Hide quoted text — Show quoted text -> Finally, electrical engineering folklore says that the developers of the early > radar sets (circa WWII) all died early deaths from cancer. This was largely > due to the fact that they stood in front of the radar dishes during the winter > to warm themselves up. Note: this was inches or feet from megawatt > transmitters at Gigahertz frequencies. They wouldn’t have gotten warm in front > of them if the RF energy didn’t affect their water molecules; but if the water > was resonant at the freq’s they were using, the scientists would probably have > exploded! Also, apparently the wife of the inventor of modern x-ray > photography died early from cancer since she was her husband’s primary guinea > pig for his photography experiments. Now xrays are really particles, so
Whoa whoa!, stop the bus! X-rays are particles? I thought X-rays are RF energy at a given frequency. So if X-rays are particles, is light a particle, and microwaves, and radio waves? Yes there is debate amoug scientists on wether RF radiation is a wave propagating through space or particles moving through space, but you seem to have taken both positions. So what is light, particle or wave? > they’re not directly relevant, however, the higher in frequency you go, the > higher energy the resulting field (or whatever) has. The higher the energy, > the more likely you’ll begin to see cancer, chromosome damage, etc. regardless > of whether water resonates at a given frequency. > Final note: I have a GSM/PCS phone (Sprint Spectrum). It’s 900 MHz, and > although I think it’s "safe", you won’t find me using it more than a couple of > minutes a day. Also, I won’t intentionally put it next to my head while it’s > first connecting/searching (ie transmitting max power). You never know….
You never know what? The phones going to explode in your ear? Why do you think the phone will not operate at full power after you connect your call? Sounds like your attempting to scare people with your paranoid phobia. If you want to have a "rational discussion" on the subject, leave out the comments suggesting answers about things you admitingly don’t know. That only plays on the fear of the ignorant. Many people don’t or can’t understand this whole radio thing, and trust the opinion of someone with the word "Engineer" in thier .sig file. If you want credibility (in my book), base your statements on facts, not beliefs. > / Roger Ishimoto Mind of an Engineer > / Principal Systems Engineer Soul of a Father/Husband/Son > / E-Systems, Falls Church Division Body of Untapped Potential > / 703-560-5000 x4052 Blood of a Samurai
Disclaimer: The above post is the opinion of Bill Paul, not Qualcomm Inc.
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>Check the frequency. 2450 MHz is the frequency used in micro wave >owens, not in wireless communication. 2450 MHz is also the resonant >frequency of the water molecule (IMO, I won’t check this from a >physics book now) – the reason why these owens work. 900 MHz >micro wave owen just would not work.
I don’t think this is true. I have seen no evidence of water molecule resonances anywhere near this frequency in graphs of water absorbtion vs frequency. If anyone knows different – PLEASE quote a reference to the experimental data. John Walliker
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>>Also, there will be a study published in the International Journal >of Radiation Biology by Dr. Narendra Singh and Dr. Henry Lai. These >doctors found single & double breaks in brain cells of rats that >received a continuous dose of RF radiation at 2.45 GHz. The >researchers claim that, "DNA strands could lead to disruption of cell >functions, carcinogenesis and cell death. Cumulative DNA damage >could be a cause of accelerated aging and neurodegenerative >disorders."
What was the purpose of the tests that tried to nuke rats? If it was to test the effect of microwave ovens on rats, then fine – put the rats in the microwave, set it for 99 minutes at "cook" and wait for the fireworks. However, there is NO WAY you can take the results of these tests and attribute the same effects to cellular telephones. The frequency of 2.4Ghz is the frequency of a microwave. A GSM cellular uses 900Mhz (0.9Ghz) A microwave oven puts out between 500 watts and 1 kilowatt. A GSM cellular puts out an average of 0.25w (250 MILLIwatts). It’s actually a 2 watt transmitter, but it only transmits for 1/8 of the time due to the time- slicing way that GSM works. And that 2 watts is only used when initially logging on and when the base station asks the phone to speak up – normally the phone will be set at a lower power level. In other words, the results are BOLLOCKS when connected wjth cellular phones. Alan. — * Push to test … <CLICK> … Release to detonate *
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I missed the beginning of this thread…. There seem to be two issues: 1) someone’s pager doesn’t work in close proximity to a transmitter site 2) someone is concerned about the health issues of being near a transmitter site. > The improper operation can be caused by a number of factors…. > It is also possible (and probably more likely) that your pager cannot > reject unwanted signals well enough.
RF receivers are all subject to swamping by other signals which are close by in frequency and/or much higher in amplitude. This is called the ‘capture effect’. Within the capabilities of the receiver, a stronger signal will win out over a weaker one. More complex and costly receivers are required to prevent undesired capture effects. Normally, frequencies are allocated to avoid the majority of problems of this sort. (ie spaced far enough apart and with low enough allowed power, based upon the complexity of the receivers to be used.) In some situations, a receiver just can’t correctly handle the RF power that its getting. There are 2 main reasons: 1) the stronger, undesired signal is just too close in frequency for the receiver to resolve and reject it. This can happen anywhere (ie not necessarily close to a transmitter) if the desired signal is just barely detectible and a close by (in frequency) stronger signal appears. This is like sitting in a restaurant, trying to listen to a conversation at the next table, while people are talking at your table. And 2) the stronger signal, if it’s strong enough, can desensitize the front end circuits of the receiver (ie if there is Automatic Gain Control). The receiver does this to protect itself, assuming that the strong signal is the desired one and is the one that the user is trying to ‘hear’. Of course, if it isn’t the desired one, the real desired one just gets pushed down into the noise as the gain is decreased. You usually need a really strong signal for this to happen. This is like trying to listen to someone talking while standing next to a jet engine. Your ears desensitize themselves (for protection) and all you get is the person moving their lips as they try to talk to you. The distinction between the two scenarios is slim… the point is that there are two possible reasons why the receiver doesn’t work. The first is unlikely for a pager, due to frequency allocations. The second is likely if the pager is near a transmitter that is close by in frequency and physical proximity. AS for safety near a transmitter. There are several points that should be considered in a rational discussion. Points that have not been made, yet. 1) Radiated power, dissipates in proportion to the square of the distance. ie, if you move twice as far away, you get one fourth the power. 10 times farther, 100 times less power, etc. I’d rather be 50 feet from a 200 watt transmitter than 2 inches from a 2 watt transmitter any day. 2) Grounded metal plates completely block RF energy. Most transmitter antennas are monopoles. This means that they require a ground plane beneath them to work efficiently (like your car cellular antenna… it works best if mounted in the CENTER of your metal roof). Underneath the metal plate, there is essentially NO RF field except to the extent that the metal plate isn’t ‘good’ enough for the frequency/power of the transmitter. 3) All monopole and dipole antennas (working in their designed frequency band) have a null directly below and above them. A dipole has a torroidal (ie donut) shaped RF field. If you stand directly below the antenna (with no near field reflectors), there is NO RF energy from that antenna. In other words, I’d rather live UNDER a transmitter than next door to one! (note that horizontal power line VLF fields radiate TO the ground, so that max field strength is directly underneath them) Finally, electrical engineering folklore says that the developers of the early radar sets (circa WWII) all died early deaths from cancer. This was largely due to the fact that they stood in front of the radar dishes during the winter to warm themselves up. Note: this was inches or feet from megawatt transmitters at Gigahertz frequencies. They wouldn’t have gotten warm in front of them if the RF energy didn’t affect their water molecules; but if the water was resonant at the freq’s they were using, the scientists would probably have exploded! Also, apparently the wife of the inventor of modern x-ray photography died early from cancer since she was her husband’s primary guinea pig for his photography experiments. Now xrays are really particles, so they’re not directly relevant, however, the higher in frequency you go, the higher energy the resulting field (or whatever) has. The higher the energy, the more likely you’ll begin to see cancer, chromosome damage, etc. regardless of whether water resonates at a given frequency. Final note: I have a GSM/PCS phone (Sprint Spectrum). It’s 900 MHz, and although I think it’s "safe", you won’t find me using it more than a couple of minutes a day. Also, I won’t intentionally put it next to my head while it’s first connecting/searching (ie transmitting max power). You never know…. / Roger Ishimoto Mind of an Engineer / Principal Systems Engineer Soul of a Father/Husband/Son / E-Systems, Falls Church Division Body of Untapped Potential / 703-560-5000 x4052 Blood of a Samurai
Response:
RE: Pager interference You do not need any equipment except a computer. You need an application that will compare the frequencies of the transmitters in question with frequencies used by your pager (including intermediate frequencies used by the superheterodyne circuits). Any computer literate amatuer radio operator will probably have an intermod program. The frequencies used by the transmitters are a matter of public record and should also be posted near the transmitters. (You can also use one of those ubiquitous cheap frequency counters if you can get close enough). I suggest you switch paging companies to one using a transmitter near you; that is until your brain melts from the RF. Cheers.
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– Hide quoted text — Show quoted text ->If you want to make a case for these devices being hazardous (as you >evidently do), you’ll have to resort to referencing speculative >conclusions and fringe literature. You’re likely exposed to much >more serious and real hazards by your wife’s perfume, the water you >drink, sugar substitutes, outgassing from the adhesives used within >your home, or pesticides and additives in the the food >you eat. >Of course, these things won’t pay for your new pager. > Harry C. >Yes, I know what you mean. But at times we all worry. >In Great Britian a suit may be filed by Lyall Smith, a salesman >who used is cell phone extensively ($1,000 a month cell bills) >and developed nerve damage behind his right ear..which impaired >his speech. His lawyer is Martyn Day who specializes in evnironmental >effects of non-ionizing radiation. >Also, there will be a study published in the International Journal >of Radiation Biology by Dr. Narendra Singh and Dr. Henry Lai. These >doctors found single & double breaks in brain cells of rats that >received a continuous dose of RF radiation at 2.45 GHz. The >researchers claim that, "DNA strands could lead to disruption of cell >functions, carcinogenesis and cell death. Cumulative DNA damage >could be a cause of accelerated aging and neurodegenerative >disorders." >The EPA considered setting federal RF radiation guidelines in the >1980’s but ceased work on the project for budget and policy reasons. >Remember the above researchers said "could…….lead to….." >Nobody really knows. That’s why I asked. >=KEN=
Boy have YOU been fed a hairy-fairy story!! The researchers, who were privately funded by foundation grants, generally gave UP looking for a correlation!! Yes, there WAS one guy with something weird behind his ear. We have not seen another such! Can you say "a high number of standard deviations out of the correlation curve"? I thought you could! Also, what ARE "single and double breaks" in brain cells? Not knowing what dendritic and synaptic breaks even MEAN yet, I believe those terms are only technically defined in TENNIS!! Also, no mention of intensity for the 2.45 GHz was cited, and we ALL know, that from whatever causeS, plural, DNA errors continue to occur and either cause the immediate death of the cell, or cause it to wither and slowly die, or attract white cells or antibodies to kill it, or they simply don’t act right, and that causes aging, but actually a carcinoma and rampant cell growth is one of the LEAST likely outcomes! I saw no mention of the number of base-pair errors, like a real geneticist would do! The whole thing sounds like some idiot wrote it from carefully mal-selected fragments and published it in magazines that sell herbs by mail to cure cancer and think nature is loving and gentle!! The deafening stupidity is hard to believe!! -Steve — mirrored: ftp://ieee.cas.uc.edu/pub/electronics/faqs/ftp.armory.com and Europe: ftp://ftp.cised.unina.it/pub/electronics/ftp.armory.com and Oz: ftp://ftp.peninsula.apana.org.au/pub/electronics/ftp.armory.com
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> In Great Britian a suit may be filed by Lyall Smith, a salesman > who used is cell phone extensively ($1,000 a month cell bills) > and developed nerve damage behind his right ear..which impaired > his speech. His lawyer is Martyn Day who specializes in evnironmental > effects of non-ionizing radiation.
Anyone can file a suit on almost whatever grounds – they are usually after money. Nerve damage (assumed) suggests to me something like mechanical damage. Pressing phone against the ear, holding your head in strange position when trying to do something else with our hands while talking on the phone. Using too heavy headphones will make your earlobes ache. > Also, there will be a study published in the International Journal > of Radiation Biology by Dr. Narendra Singh and Dr. Henry Lai. These > doctors found single & double breaks in brain cells of rats that > received a continuous dose of RF radiation at 2.45 GHz. The > researchers claim that, "DNA strands could lead to disruption of cell > functions, carcinogenesis and cell death. Cumulative DNA damage > could be a cause of accelerated aging and neurodegenerative > disorders."
Check the frequency. 2450 MHz is the frequency used in micro wave owens, not in wireless communication. 2450 MHz is also the resonant frequency of the water molecule (IMO, I won’t check this from a physics book now) – the reason why these owens work. 900 MHz micro wave owen just would not work. So 2450 MHz is really a special case – researchers are making sure that using micro wave owens is safe. Maybe you should ban these owens – after all their power levels are much higher than any pager or cell phone transmitter – 5 to 10 times higher. > Nobody really knows. That’s why I asked.
What do you mean by "really knows"? Nothing is 100% sure and if you ask a lawyer they are sure to agree with your problem or complaint – after all they are just after the money. — Juha Veijalainen http://personal.eunet.fi/pp/karhu/ Helsinki, Finland http://www.vn.fi/vn/um/ ** Mielipiteet omiani / Opinions personal, facts suspect **
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- Hide quoted text — Show quoted text -> : have received your letter…sent an engineer to the site..and > : > The improper operation can be caused by a number of factors. Yes, it > is possible that an improperly operating transmitter can transmit a > signal at the wrong frequency, the wrong frequency being the frequency > of operation of your pager. This would interfere with the operation of > your pager. > It is also possible (and probably more likely) that your pager cannot > reject unwanted signals well enough. In this case, you can have a > transmitter which is putting out an absolutely pure signal only on its > proper channel, and your pager would not work. In this case, the > problem is between you and the manufacturer of the pager. The specs > that receivers must meet are very lax compared to what transmitters > must meet. Just because you have a receiver, doesn’t mean that it > is properly designed. Or, it could be designed to operate in 99.9% > of cases, and you are in the .1% of the cases where it won’t operate. > Since the company sent a technician out to check the operation of the > transmitter, I suspect that your pager is at fault. > : 2. There has been alot a speculation, as well as professional
Mr. B- your reply couldn’t have been stated more accurately. It is encouraging to see a high degree of competence in this otherwise lacking newsgroup. Sincerely, John J. Mierzwa WA3YUR Scott Communications, Inc.
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>In Great Britian a suit may be filed by Lyall Smith, a salesman >who used is cell phone extensively ($1,000 a month cell bills) >and developed nerve damage behind his right ear..which impaired >his speech. His lawyer is Martyn Day who specializes in evnironmental >effects of non-ionizing radiation.
[ stuff deleted ] >Nobody really knows. That’s why I asked.
Good to know that if the scientists don’t know anything about the effects of RF on the human body at least the lawyers do! 
— Mark Mark Wilkins | "With the dog and the weapons, I’m Walt Disney Feature Animation | prepared for the future…" Burbank, CA | I do not speak for The Walt Disney Company!
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- Hide quoted text — Show quoted text – >"""Chang) writes: >"""> >"""> >""">>Hopefully, someone reading this, could offer some helpful answers >""">>and suggestions. Personally, I feel the 800 + 900mhz transmitters >""">>should have been erected in an area where humans would not be >""">>exposed on a constant, 24-hours basis. >"""> >""">Interesting comment. >"""> >""">Ever wondered how your little pager actually received its messages? >""">Or your TV, radio and some remote controllers for your garage door? >"""> >""">I wish you the best of luck finding a radiation-free zone. Perhaps >""">you might wish to erect a Faraday cage and make that your home… >"""> >""">cheers, >""">–wc >""">– >""" >""" >"""Yes, that would be nice…but not practical! The questions is.. >"""basically, are the transmitters on top of a residential building >"""a health hazard? That was the question! >""" >"""=KEN= > Just a second… > How high a power are you talking about? > Cellular only sends out 20 watts at the back of the transmiter bay. > Then it goes up a coax line that drops over half of that power in > line loss.. > So now we are down around 10 watts… hummmm high power? > BTW… You know you have over 400 WATTS on that little microwave > in the kitchen that you look into the window to see if your peas > are cooked… You think that is ok , Don’t you? > Who told you it was bad for you… some Lawyer in a court case? > BTW did they win that case or was it just talk? > You sound like a bunch of sheep in a pasture….
The most often cited and most startling thing about any supposed danger from E&M radiation or exposure as they do more and more testing to look for any health risk is how much harder and harder it had become to FIND anything real the more and the harder and more carefully we looked for it!! Read the literature and journals lately, Geez!!! We have literally MILLIONS of workers in factories who have been exposed to all manner of E&M radiation, and this has been for close to the last 100 years!! If you can’t put occupational statistics and health statistics together and come up with even a LITTLE bit something funny, after DECADES of people eating lunch with their testicals sitting flat down on top giant transformers in operation, or working huge tonnage presses with gigantic high-torque motors, and if when comparing them to other workers, like park rangers and office workers from the ’20’s and ’30’s, where they used mechanical tools only, by and large, and if you STILL can’t find anything, THEN WHAT would *YOU* think about it????? Well surprise!!! That’s the current consclusion!! Most people working on this 5 years ago have given up hope of finding anything and gone back to other research!!! -Steve — mirrored: ftp://ieee.cas.uc.edu/pub/electronics/faqs/ftp.armory.com and Europe: ftp://ftp.cised.unina.it/pub/electronics/ftp.armory.com and Oz: ftp://ftp.peninsula.apana.org.au/pub/electronics/ftp.armory.com
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>If you want to make a case for these devices being hazardous (as you >evidently do), you’ll have to resort to referencing speculative >conclusions and fringe literature. You’re likely exposed to much >more serious and real hazards by your wife’s perfume, the water you >drink, sugar substitutes, outgassing from the adhesives used within >your home, or pesticides and additives in the the food >you eat. >Of course, these things won’t pay for your new pager. > Harry C.
Yes, I know what you mean. But at times we all worry. In Great Britian a suit may be filed by Lyall Smith, a salesman who used is cell phone extensively ($1,000 a month cell bills) and developed nerve damage behind his right ear..which impaired his speech. His lawyer is Martyn Day who specializes in evnironmental effects of non-ionizing radiation. Also, there will be a study published in the International Journal of Radiation Biology by Dr. Narendra Singh and Dr. Henry Lai. These doctors found single & double breaks in brain cells of rats that received a continuous dose of RF radiation at 2.45 GHz. The researchers claim that, "DNA strands could lead to disruption of cell functions, carcinogenesis and cell death. Cumulative DNA damage could be a cause of accelerated aging and neurodegenerative disorders." The EPA considered setting federal RF radiation guidelines in the 1980’s but ceased work on the project for budget and policy reasons. Remember the above researchers said "could…….lead to….." Nobody really knows. That’s why I asked. =KEN=
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: I agree with you! That’s why we were asking for "professional" : opinions about 200-300 watt transmitters, on a rooftop, at : 900 mhz. : : Doesn’t seem like anyone can say…..objectively. : : =KEN= Wrong, Ken. One can objectively state that there is no demonstrated biological hazard documented to date resulting from equivalent transmitters operating in similar environments at corresponding power levels. Many year of research have gone into demonstrating biohazard links with such devices, with essentially negative findings — really not surprising considering the large number of healthy individuals who have been daily exposed to much higher levels of r.f. for years on end. If you want to make a case for these devices being hazardous (as you evidently do), you’ll have to resort to referencing speculative conclusions and fringe literature. You’re likely exposed to much more serious and real hazards by your wife’s perfume, the water you drink, sugar substitutes, outgassing from the adhesives used within your home, or pesticides and additives in the the food you eat. Of course, these things won’t pay for your new pager. Harry C.
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– Hide quoted text — Show quoted text ->A similar situation happened to a friend of mine years ago. The property >being used for the transmitter was on county land, and the transmitter was >within specs but the neighbors were getting interference on TVs and even >organs. The newighbors went to the county board of supervisors meeting >and talked about their problem, and since the owner of the transmitter was >also notified, he was also present. There was a heated argument, and the >supervisors finally voted to raise the rent of the owner, so he eventually >had to take his pager tx to another site since he couldn’t afford the rent. >What this boils down to is that you might get better results by going >thru other channels such as your city council. They could declare this >as a nuisance, or they could rezone the high rise for non commercial use >so that the owners could not rent to these companies. There are other >ways besides the technical end of the matter to resolve this problem. >And remember above all that numbers do count. So mnake sure that you >get as many people as possible to rally to the meetings, and make sure >that you use all means possible to get the word out. The more people at >the meetings, the more the problem will be taken seriously. >Why do you oppose to mobile radio by principle? >I.e. before it is clear what the real problem is? >Why oppose to a base station site if it turns out that it is just a >poor design of a pager model? Or poor coverage of the paging systems with >respect to the fact that it has to coexist with other networks? >Or an old TV set with poor shielding and interference rejection? >Technical things may date out. You are generally also not allowed to use >a highway with a car of 1900 because you are too slow. >All this is no reason to incite people. >Generally be carefully about inciting people unless your really know >what the problem is about. Everything else is just a surgeon cutting >into the body somewhere without a diagnosis! >r., >Hermann
I agree with you! That’s why we were asking for "professional" opinions about 200-300 watt transmitters, on a rooftop, at 900 mhz. Doesn’t seem like anyone can say…..objectively. =KEN=
Response:
- Hide quoted text — Show quoted text – >A similar situation happened to a friend of mine years ago. The property >being used for the transmitter was on county land, and the transmitter was >within specs but the neighbors were getting interference on TVs and even >organs. The newighbors went to the county board of supervisors meeting >and talked about their problem, and since the owner of the transmitter was >also notified, he was also present. There was a heated argument, and the >supervisors finally voted to raise the rent of the owner, so he eventually >had to take his pager tx to another site since he couldn’t afford the rent. >What this boils down to is that you might get better results by going >thru other channels such as your city council. They could declare this >as a nuisance, or they could rezone the high rise for non commercial use >so that the owners could not rent to these companies. There are other >ways besides the technical end of the matter to resolve this problem. >And remember above all that numbers do count. So mnake sure that you >get as many people as possible to rally to the meetings, and make sure >that you use all means possible to get the word out. The more people at >the meetings, the more the problem will be taken seriously.
Why do you oppose to mobile radio by principle? I.e. before it is clear what the real problem is? Why oppose to a base station site if it turns out that it is just a poor design of a pager model? Or poor coverage of the paging systems with respect to the fact that it has to coexist with other networks? Or an old TV set with poor shielding and interference rejection? Technical things may date out. You are generally also not allowed to use a highway with a car of 1900 because you are too slow. All this is no reason to incite people. Generally be carefully about inciting people unless your really know what the problem is about. Everything else is just a surgeon cutting into the body somewhere without a diagnosis! r., Hermann
Response:
- Hide quoted text — Show quoted text – >I have several questions to ask anyone who feels qualified to >answer them. With a lack of advanced technical knowledge I would >appreciate any answers. >1. If the transmitters on that roof (1,500 feet away) are causing > pagers in this neighborhood to operate improperly, what legal > obligation would the companies have to correct the situation. >2. There has been alot a speculation, as well as professional > testimony in cellular (brain tumor) court cases where people > and doctors claim that 900mhz radiation can cause damage to > the human body. Most of these issues have involved portable > cellular phones with a power of 6/10 of a watt, near the head. > Keeping this in mind, does anyone know if the residents in > the high-rise building, the garden apartments 500 feet away, > or residents in my neighborhood 1,500 to 3,000 feet away could > possibly be in danger from the 250 watt transmitters which are > usually transmitting. >3. What type of equipment would be needed to take an exact > measurement of these transmitter signals? Who would we call? >One of the residents in my neigborhood is running for U.S. Congress >and he, too, is very concerned about the possible hazards which >*may* be caused by the transmitters. >Hopefully, someone reading this, could offer some helpful answers >and suggestions. Personally, I feel the 800 + 900mhz transmitters >should have been erected in an area where humans would not be >exposed on a constant, 24-hours basis.
I think that too many questions are unclear – who sends what power at what frequency with which antenna into what direction? Is it a bursty transmission or continuous … – What about the antenna directivity? I would expect that the antennas have a rather small vertical aperture so the residents near or in the building where the antenna stands get not very much radiation. And keep in mind that the power density of the radiated field decreases with the square of the distance. So the cellular handies are a kind of worst case because they are so near. For ususal cellular transmitters for base stations the safe distances can easily be fulfilled. And please keep in mind that broadcasting (eg TV) use significantly higher transmit powers (MegaWatts!) and the receivers (Radios TV-sets) are very poor in reception compared to cellular equipment. So I would not be frightned by cellular rather than by TV 
Furthermore cellular systems are designed interference limited. This means that transmitted power causes interference within the own network. Thus no network transmits 24h but shuts down transmitters or reduces power whenever possible. Keep away from politicians beeing concerned about things that possibly may be especially if their possibility to understand the problem is limited to "beeing concerned". In your situation I would try to get the advice of a professional consultant because 50%-answers would not help you. Of course it is possible to perform high quality field-strength measurements with measurement receivers and spectrum analysers. However this is a job for a well equipped lab. But first of all it must be decided carefully which question should really be answered by this measurement. And of course it is possible to find out the reason why your pager does not work. Regards, Hermann
Response:
: What this boils down to is that you might get better results by going : thru other channels such as your city council. They could declare this : as a nuisance, or they could rezone the high rise for non commercial use : so that the owners could not rent to these companies. There are other : ways besides the technical end of the matter to resolve this problem. : : And remember above all that numbers do count. So mnake sure that you : get as many people as possible to rally to the meetings, and make sure : that you use all means possible to get the word out. The more people at : the meetings, the more the problem will be taken seriously. : Really, John? Lacking evidence that there is a technical problem with the transmitters, a demonstrable health hazard, or a regulatory infraction, you would resort to attempted intimidation? Where did you get your training, a KKK activist’s manual? I’d be more inclined to suggest that the poster attempt to solve the problem at its source (likely his pager) rather than attempting to modify (quiet) the environment to suit his personal liking. I may not care for motorcycles operating in my residential neighborhood, however, so long as they’re being operated legally and safely, I have no moral right to attempt intimidating their owners. This is called responsible citizenship — something normally associated with civilized behavior. Harry C.
Response:
>Hopefully, someone reading this, could offer some helpful answers >and suggestions. Personally, I feel the 800 + 900mhz transmitters >should have been erected in an area where humans would not be >exposed on a constant, 24-hours basis.
Interesting comment. Ever wondered how your little pager actually received its messages? Or your TV, radio and some remote controllers for your garage door? I wish you the best of luck finding a radiation-free zone. Perhaps you might wish to erect a Faraday cage and make that your home… cheers, –wc —
Response:
– Hide quoted text — Show quoted text -Chang) writes: >Hopefully, someone reading this, could offer some helpful answers >and suggestions. Personally, I feel the 800 + 900mhz transmitters >should have been erected in an area where humans would not be >exposed on a constant, 24-hours basis. >Interesting comment. >Ever wondered how your little pager actually received its messages? >Or your TV, radio and some remote controllers for your garage door? >I wish you the best of luck finding a radiation-free zone. Perhaps >you might wish to erect a Faraday cage and make that your home… >cheers, >–wc >–
Yes, that would be nice…but not practical! The questions is.. basically, are the transmitters on top of a residential building a health hazard? That was the question! =KEN=
Response:
"""Chang) writes:
""">
"""> """>>Hopefully, someone reading this, could offer some helpful answers """>>and suggestions. Personally, I feel the 800 + 900mhz transmitters """>>should have been erected in an area where humans would not be """>>exposed on a constant, 24-hours basis. """> """>Interesting comment. """> """>Ever wondered how your little pager actually received its messages? """>Or your TV, radio and some remote controllers for your garage door? """> """>I wish you the best of luck finding a radiation-free zone. Perhaps """>you might wish to erect a Faraday cage and make that your home… """> """>cheers, """>–wc """>– """ """ """Yes, that would be nice…but not practical! The questions is.. """basically, are the transmitters on top of a residential building """a health hazard? That was the question! """ """=KEN= Just a second… How high a power are you talking about? Cellular only sends out 20 watts at the back of the transmiter bay. Then it goes up a coax line that drops over half of that power in line loss.. So now we are down around 10 watts… hummmm high power? BTW… You know you have over 400 WATTS on that little microwave in the kitchen that you look into the window to see if your peas are cooked… You think that is ok , Don’t you? Who told you it was bad for you… some Lawyer in a court case? BTW did they win that case or was it just talk? You sound like a bunch of sheep in a pasture….
Response:
A similar situation happened to a friend of mine years ago. The property being used for the transmitter was on county land, and the transmitter was within specs but the neighbors were getting interference on TVs and even organs. The newighbors went to the county board of supervisors meeting and talked about their problem, and since the owner of the transmitter was also notified, he was also present. There was a heated argument, and the supervisors finally voted to raise the rent of the owner, so he eventually had to take his pager tx to another site since he couldn’t afford the rent. What this boils down to is that you might get better results by going thru other channels such as your city council. They could declare this as a nuisance, or they could rezone the high rise for non commercial use so that the owners could not rent to these companies. There are other ways besides the technical end of the matter to resolve this problem. And remember above all that numbers do count. So mnake sure that you get as many people as possible to rally to the meetings, and make sure that you use all means possible to get the word out. The more people at the meetings, the more the problem will be taken seriously. : : I am posting this message to different newsgroups, hoping I can get : : a professional and educated opinion about a potentially dangerous : : situation. : : I live next to an interstate highway that intersects with a county : : roadway. At this intersection, which is about 1,500 feet from my : : home is a 16-story high rise apartment building. : : About two years ago I noticed that the reception on my pager was : : apparently getting worse because I was missing pages that should : : have been received. About six months ago I learned the owners of : : the high-rise building had rented to roof to many companies to : : place their transmitters. (This includes a low band 35 mzh band, : : 450 mhz bands, 800 mhz [cellular] and 900 mhz [paging] bands.) : : After conducting tests, which are basically limited due to my : : knowledge, I have concluded the interference to my personal pager : : is being caused by the transmitters on that roof. I conducted : : my tests using an inexpensive scanner along with an Icom R-7000, : : which enables me to tune to any freqency and obtain a reading with : : the s-meter. While the s-meter does not actually measure the exact : : amount of radio energy..it does allow me to determine if a signal : : is strong or weak. : : There are now about six transmitter in the 900mhz band. It is : : antenna. One cellular company has transmitters there also, however : : their exact power output is unknown to me at this time. : : I spoke with other residents and now have learned they, too are : : getting "broken" pages. One of my neighbors also sells pagers, : : on five different frequencies, and he has many problems with : : reception. : : About a month ago I wrote a letter to the President of one of : : the (larger) pager companies involved. Two weeks later his : : Vice-President of Technical Operations phoned me and said, "We : : have received your letter…sent an engineer to the site..and : : our transmitters are all working within legal specifications." : : According to him, the pagers are missing pages because the receiver : : is not capable of proper adjecent channel rejection. He then : : continued to rap on about different types of formulas that I clearly : : did not understand. He did admit the transmitter were causing the : : poor/missed reception in this neighborhood. : : I have several questions to ask anyone who feels qualified to : : answer them. With a lack of advanced technical knowledge I would : : appreciate any answers. : : 1. If the transmitters on that roof (1,500 feet away) are causing : : pagers in this neighborhood to operate improperly, what legal : : obligation would the companies have to correct the situation. : The improper operation can be caused by a number of factors. Yes, it : is possible that an improperly operating transmitter can transmit a : signal at the wrong frequency, the wrong frequency being the frequency : of operation of your pager. This would interfere with the operation of : your pager. : It is also possible (and probably more likely) that your pager cannot : reject unwanted signals well enough. In this case, you can have a : transmitter which is putting out an absolutely pure signal only on its : proper channel, and your pager would not work. In this case, the : problem is between you and the manufacturer of the pager. The specs : that receivers must meet are very lax compared to what transmitters : must meet. Just because you have a receiver, doesn’t mean that it : is properly designed. Or, it could be designed to operate in 99.9% : of cases, and you are in the .1% of the cases where it won’t operate. : Since the company sent a technician out to check the operation of the : transmitter, I suspect that your pager is at fault. : : 2. There has been alot a speculation, as well as professional : : testimony in cellular (brain tumor) court cases where people : : and doctors claim that 900mhz radiation can cause damage to : : the human body. Most of these issues have involved portable : : cellular phones with a power of 6/10 of a watt, near the head. : : Keeping this in mind, does anyone know if the residents in : : the high-rise building, the garden apartments 500 feet away, : : or residents in my neighborhood 1,500 to 3,000 feet away could : : possibly be in danger from the 250 watt transmitters which are : : usually transmitting. : Power density falls off as square of the distance. Just think of the : RF power being spread over a sphere. The surface area of a sphere : increases by the square of the radius. : Assume that the antenna of the cellular phone is 6" from the users : head (.5 foot), running .6 watts. This is equivalent to running : 2.4 watts at a distance of 1 foot. : Now, take the case of the 250 watt transmitter : 500 feet away. Normalizing this to 1 foot away, it is equivalent to : running 1 milliwatt 1 foot away. This sort of power density is much : lower than what your microwave oven is allowed to leak. : The cell phone is running a power density 2400 times higher. : The cell cite transmitters may well use antennas with gain higher than : the antenna gain of a cell phone. But antenna gain comes as a result : of focusing the power in one direction. If you are outside of that : main direction, you actually get less power. And even if you were : at the direction with peak gain, you would not expect more than : about a factor of 4 for power gain over that gain of a cell phone : antenna. : : 3. What type of equipment would be needed to take an exact : : measurement of these transmitter signals? Who would we call? : You would need a calibrated antenna and a calibrated receiver. It is : possible to get by without a calibrated antenna if you can carefully : construct a tuned dipole antenna, since it is a physical element with : known gain. There is no substitute for a calibrated receiver, except : maybe a receiver with a signal strength meter, and a calibrated signal : source which can substitute a signal of known frequency and strength. : : One of the residents in my neigborhood is running for U.S. Congress : : and he, too, is very concerned about the possible hazards which : : *may* be caused by the transmitters. : I just hope your neighbor takes the time to become well informed about : the technical issues before producing legislation. : : Hopefully, someone reading this, could offer some helpful answers : : and suggestions. Personally, I feel the 800 + 900mhz transmitters : : should have been erected in an area where humans would not be : : exposed on a constant, 24-hours basis. : Donald Borowski WA6OMI Hewlett-Packard, Spokane Division : "Angels are able to fly because they take themselves so lightly." : -G.K. Chesterton — #======P=G=P==k=e=y==a=v=a=i=l=a=b=l=e==u=p=o=n==r=e=q=u=e=s=t======# | Rancho Santiago Community College District | deltanet.com | | 17th St at Bristol Santa Ana, CA 92706 | http://rsc.rancho| | My opinions are my own, and not my employer’s. | .cc.ca.us | | Most FAQs are available through Thomas Fine’s WWW FAQ archive: | |http://www.cis.ohio-state.edu:80/hypertext/faq/usenet/FAQ-List.html| | "You can flame your brains out — it won’t take long." | #===T=u=z=l=a==C=o=m=p=a=n=y=.=.===t=h=r=e=e=’=s==L=e==C=r=o=w=d=!==#
Response:
: I am posting this message to different newsgroups, hoping I can get : a professional and educated opinion about a potentially dangerous : situation. : I live next to an interstate highway that intersects with a county : roadway. At this intersection, which is about 1,500 feet from my : home is a 16-story high rise apartment building. : About two years ago I noticed that the reception on my pager was : apparently getting worse because I was missing pages that should : have been received. About six months ago I learned the owners of : the high-rise building had rented to roof to many companies to : place their transmitters. (This includes a low band 35 mzh band, : 450 mhz bands, 800 mhz [cellular] and 900 mhz [paging] bands.) : After conducting tests, which are basically limited due to my : knowledge, I have concluded the interference to my personal pager : is being caused by the transmitters on that roof. I conducted : my tests using an inexpensive scanner along with an Icom R-7000, : which enables me to tune to any freqency and obtain a reading with : the s-meter. While the s-meter does not actually measure the exact : amount of radio energy..it does allow me to determine if a signal : is strong or weak. : There are now about six transmitter in the 900mhz band. It is : antenna. One cellular company has transmitters there also, however : their exact power output is unknown to me at this time. : I spoke with other residents and now have learned they, too are : getting "broken" pages. One of my neighbors also sells pagers, : on five different frequencies, and he has many problems with : reception. : About a month ago I wrote a letter to the President of one of : the (larger) pager companies involved. Two weeks later his : Vice-President of Technical Operations phoned me and said, "We : have received your letter…sent an engineer to the site..and : our transmitters are all working within legal specifications." : According to him, the pagers are missing pages because the receiver : is not capable of proper adjecent channel rejection. He then : continued to rap on about different types of formulas that I clearly : did not understand. He did admit the transmitter were causing the : poor/missed reception in this neighborhood. : I have several questions to ask anyone who feels qualified to : answer them. With a lack of advanced technical knowledge I would : appreciate any answers. : 1. If the transmitters on that roof (1,500 feet away) are causing : pagers in this neighborhood to operate improperly, what legal : obligation would the companies have to correct the situation. The improper operation can be caused by a number of factors. Yes, it is possible that an improperly operating transmitter can transmit a signal at the wrong frequency, the wrong frequency being the frequency of operation of your pager. This would interfere with the operation of your pager. It is also possible (and probably more likely) that your pager cannot reject unwanted signals well enough. In this case, you can have a transmitter which is putting out an absolutely pure signal only on its proper channel, and your pager would not work. In this case, the problem is between you and the manufacturer of the pager. The specs that receivers must meet are very lax compared to what transmitters must meet. Just because you have a receiver, doesn’t mean that it is properly designed. Or, it could be designed to operate in 99.9% of cases, and you are in the .1% of the cases where it won’t operate. Since the company sent a technician out to check the operation of the transmitter, I suspect that your pager is at fault. : 2. There has been alot a speculation, as well as professional : testimony in cellular (brain tumor) court cases where people : and doctors claim that 900mhz radiation can cause damage to : the human body. Most of these issues have involved portable : cellular phones with a power of 6/10 of a watt, near the head. : Keeping this in mind, does anyone know if the residents in : the high-rise building, the garden apartments 500 feet away, : or residents in my neighborhood 1,500 to 3,000 feet away could : possibly be in danger from the 250 watt transmitters which are : usually transmitting. Power density falls off as square of the distance. Just think of the RF power being spread over a sphere. The surface area of a sphere increases by the square of the radius. Assume that the antenna of the cellular phone is 6" from the users head (.5 foot), running .6 watts. This is equivalent to running 2.4 watts at a distance of 1 foot. Now, take the case of the 250 watt transmitter 500 feet away. Normalizing this to 1 foot away, it is equivalent to running 1 milliwatt 1 foot away. This sort of power density is much lower than what your microwave oven is allowed to leak. The cell phone is running a power density 2400 times higher. The cell cite transmitters may well use antennas with gain higher than the antenna gain of a cell phone. But antenna gain comes as a result of focusing the power in one direction. If you are outside of that main direction, you actually get less power. And even if you were at the direction with peak gain, you would not expect more than about a factor of 4 for power gain over that gain of a cell phone antenna. : 3. What type of equipment would be needed to take an exact : measurement of these transmitter signals? Who would we call? You would need a calibrated antenna and a calibrated receiver. It is possible to get by without a calibrated antenna if you can carefully construct a tuned dipole antenna, since it is a physical element with known gain. There is no substitute for a calibrated receiver, except maybe a receiver with a signal strength meter, and a calibrated signal source which can substitute a signal of known frequency and strength. : One of the residents in my neigborhood is running for U.S. Congress : and he, too, is very concerned about the possible hazards which : *may* be caused by the transmitters. I just hope your neighbor takes the time to become well informed about the technical issues before producing legislation. : Hopefully, someone reading this, could offer some helpful answers : and suggestions. Personally, I feel the 800 + 900mhz transmitters : should have been erected in an area where humans would not be : exposed on a constant, 24-hours basis. Donald Borowski WA6OMI Hewlett-Packard, Spokane Division "Angels are able to fly because they take themselves so lightly." -G.K. Chesterton
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