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No State Sales Tax on your Purchases, Ever! Save from 3% to 10%! Cell Phone and Tower RF Radiation Meter - Price of $359. With the growth of the cell phone industry, and widespread use of cellular telephones, have come numerous complaints and even epidemiological studies claiming the low-level microwave radiation emitted by these devices are harmful to human health. Low level microwave radio frequenices (RF) are given off not only by the cell phones, but also by repeater stations placed on the roofs of apartment buildings (to eliminate "dark zones" where cell phones might otherwise be unusable), as well as from larger cellular telephone and microwave communications towers. Obtaining precise measurements of the radiations from these various devices and antennas has always posed a big problem for those wanting to have exacting information on their exposure levels.
The new Cell Phone and Tower RF Radiation Meter is designed to measure frequencies within two ranges (1 GHz or "gigahertz" = 1000 MHz or "megahertz"):
1) the range of cell phones and towers specifically (0.8 - 1.7 GHz), and
2) a broader range which encompasses cell phones, towers and other microwave exposures such as microwave ovens (which yield an emission peaking at around 2 GHz), in addition to radiofrequencies as from AM radio broadcasting towers (0.5 MHz - 3 GHz).
If you only want to measure high frequencies such as cell phones and cell phone towers, switch the Bandwidth to "Narrow". To see all microwave and radiofrequencies, switch to "Wide". An instruction sheet is included.
A selector switch allows detection in three ranges of intensity, which span from .001 to 2000 microwatts/cm2. Signal strengths may rapidly fluctuate in these frequencies, so there is a slow-fast selector switch, to smooth out the readings. The meter also now has a self-adjustment feature for zeroing and temperature-compensation, replacing an older model which required manual adjustments. It also has a low-battery indicator, and is fully portable, using only a 9-volt battery. You simply turn it on, set to the sensitivity range desired, and then to wide or narrow bandwidth for evaluation of the RF-microwave sources you wish to measure, as noted above in points 1) and 2).
This is an elegant and very useful tool for those who want to know what they are being exposed to in the cell-phone and radio-broadcasting frequency ranges, and especially for those community groups or individuals who are fighting to prevent cell phone installations from being erected close to their homes, schools and workplaces. Cell phone repeater stations are today routinely being put on the roofs of apartment and office buildings and close to schools, so that cell-phone users can get clear reception while engaging in mindless chatter in a basement location -- sometimes cell phone towers are dressed up as harmless palm trees, to hide them from an unsuspecting public. Everyone is therefore getting an increasing exposure which, due to political infiltration of our public health sector, bears little relationship to observed biological reactions or health risks. If you have ever wondered if that small hand-held cell phone all the kids are using today, or a cell-phone tower placed near to your child's school, or overhead on the roof of your apartment was putting out a tremendous blast of energy, this meter will remove that doubt entirely.
See the note below on "How Do You Know What Exposure Levels Are Safe?"
Operating Instructions
To Operate, turn the left knob clockwise to the desired sensitivity range -- to 19.999 for the most sensitive, or 1999.9 for the least sensitive scales as when exposing the meter to stronger sources.
If you only want to measure high frequencies such as cell towers and microwave ovens, switch "Bandwidth" to "Narrow". To see all RF frequencies, switch to "Wide". Make sure your hand is not blocking the top third of the meter as this can reduce the readings. The sensor is in the top-front of the meter and the meter should be held vertically upward (it measures the vertical electrical field component of the RF wave and converts that number to a power density on the display).
Because your body (and other objects) reflect radio waves, there is some ambiguity in the readings. This is especially true at the higher frequencies. You'll notice that if you first measure and then reduce the distance from your body to the meter by one inch, the reading may change. Also, as you move the meter, the reading may repeatedly go higher-lower-higher every inch or so. You should take an average in this case. Generally, the RF waves have most of their power in the vertical electrical field, but some is in the horizontal. To get a true measurement of the total RF power density propagating toward you, hold the meter vertical (with the battery-lid side facing the object you are testing) and read that number. Then turn the meter horizontal (either 90 deg. left or right of vertical, with the back still facing the object you are testing) and add that number to the vertical reading. This gives the sum of vertical and horizontal power density.
This meter uses a standard 9-volt battery (included) and has a low battery indicator on the display. Battery life is typically 3 hours of measurement time. If LOW BATTERY shows on the display, you have about 15 minutes of battery life left. Slide the back lid off (in a direction away from the 2 screws) and replace the 9 volt battery.
Additional Technical Details From the Engineer:
Technically a "power density" meter, the "Cell Phone Meter", or RF (radio frequency) Field Strength Meter detects the electric field of radio and microwaves (RF) from .5 MHz to 3 GHz, and expresses the field strength as power density (.001 to 2000 microwatts/cm2).
This is an extremely sensitive meter which can accurately measure RF background even in rural areas far from any transmitters. The meter reads true power density directly on the display. Unlike other low-cost field strength meters, this meter's frequency response does not depend on the characteristics of an external antenna; the internal detection system yields a flat response over a very wide range of frequencies.
A High-Pass selector switch allows you to measure either the full bandwidth ("Wide" = 0.5 MHz - 3 GHz) or to apply a high-pass filter ("Narrow" = 6 dB/ octive rolloff with a knee at 100 MHz) that effectively allows only 100 MHz to 3 GHz through. In practice, this high-pass selector function can be used to estimate one additional parameter: the average frequency of the RF (if it is in the range 10 MHz - 500 MHz). The Bandwidth highpass function allows through only the high frequencies such as cell towers. At the "Wide" bandwidth, all frequencies down to .5 MHz are allowed, including AM radio.
The RF Field Strength Meter is directional and it detects only the component of the electric field which has the same polarization as the long axis of the meter. That is, if only a vertically-polarized RF wave is present, but you turn the meter in the horizontal direction, it will essentially read zero. If you subsequently rotate the meter to vertical, it will then read the full power density of the RF wave. Most RF radiation has only vertical electric field, so the full strength can be read by holding the meter vertically. (At the end of this page is more information on how to read radio waves with other polarizations).
The meter has a 4 1/2 digit display which reads in three ranges: .001 to 19.999, .01 to 199.99, and .1 to 1999.9 microwatts/cm2. For comparison, a low power 100 milliwatt dipole transmitter (typical 49 MHz cordless phone) produces about .010 microwatts/cm2 at a distance of 50 feet. This is 10x the minimum sensitivity of the meter. A FAST/SLOW update switch is normally set in the FAST position so you can quickly measure changes in the RF level. However, if the field strength is fluctuating rapidly, this switch can be set to the SLOW position, which averages the reading over several seconds.
[The following goes into more detail about using the meter to estimate the average frequency of an RF signal, and also the directionality of RF measurements.]
When measuring an RF signal of unknown frequency, you may notice that the reading is different when the Bandwidth switch is set to "Wide" vs. "Narrow". If so, you can estimate the average frequency (averaged over the power density) of the RF spectrum. If it's just a wave of a single frequency, you can estimate the frequency of that wave.
This estimate is done by measuring the power density with the Bandwidth switch set at "Wide", and then measuring the power density with the switch set to "Narrow". If these numbers are the same, the average frequency is above 500 MHz. If the "Narrow" number is less than 1% of the "Wide" number, then the average frequency is below 10 MHz. If the "Narrow" number is between about 1% and 96% of the "Wide" number, you can estimate average frequency from the ratio of the two numbers. (A written table is in the instructions).
Although most commercial RF transmitters radiate with a vertical antenna and thus a vertical electric field (so you can hold the meter vertically to measure the full power density), some RF radiation also has some horizontal component, due to reflections or transmitters that have antennas not pointed vertical. If you know where the transmitter is, you will only have to perform two readings to find the transmitter's total power density at your position. These correspond to "Z" (vertical) and "X" (horizontal, but perpendicular to the direction of the transmitter). In theory, if you point the meter's long axis toward the antenna (the "Y" direction), you will not detect any radiation from that antenna. This seems counterintuitive. (In fact, there may be some diagonal reflectors near you that produce a small "Y" component coming from the transmitter, but this is not usually significant).
In practice, if the back face of the meter is facing the RF source, and the meter is read first in the vertical orientation and then it is read after being rotated 90¡ to the horizontal position (with the back face still facing the RF source), the sum of those two numbers will be the true power density from that transmitter. (This addition is a "sum of squares". That is, because power density is proportional to the square of the electric field, then the direct sum of these two numbers, and not the square root of the direct sum, will be the correct magnitude of the power density.) Most RF field sources are principally vertically polarized, in which case only the vertical reading needs to be done. To measure the full power density at a certain point in space, regardless of the sources' locations, measure the vertical first (meter pointed upward). This will usually be the majority of the RF power density. Then make two measurements 90¡ apart, with the meter's long axis pointed in the horizontal direction. For example, after the vertical measurement, measure holding the meter in a north-south orientation and then in an east-west orientation. The sum of these three numbers is the total power density at that point in space, regardless of the position of the transmitter or transmitters. An accuracy problem arises however, because your body can block RF radiation, so if an unseen transmitter is located on the opposite side of your body from the meter, the reading will be falsely low. If you hold the meter higher than your head, this problem disappears. The presence of your hand and arm will have some effect on the field strength at the meter, so the most accurate reading is taken by setting the meter on a non-metallic surface or using, for example, a plastic holder.
This meter measures the power density of radiowaves from .5 MHz to 3000 MHz (3 GHz). Accuracy in the FM, TV and cell tower frequency range (30 MHz - 2.4 GHz) is +/-25%. Sensitivity is low by 50% (-3 dB) at the frequency limits .5 MHz and 3 GHz. (Sensitivity is 25% at 5 GHz. That is, you must multiply the reading by 4 when measuring microwaves at that high a frequency. At 10 GHz, sensitivity is about 10%.)
If you trust government standards, then the levels emitted by nearly all cell phones and RF towers are defined as "safe". However, the laws which incorporate these standards were passed by the federal government over the objections of a significant dissenting scientific opinion, and one also finds tremendous differences in laws regulating exposure levels from one nation to the next. As a means to insure the growth of the cell-phone and microwave communications industry, new laws were passed in the USA during the Clinton years to "harmonize" the laws governing exposures in the different states and counties, which also were often different from each other. The law now reads, that local communities, counties and states may NOT set their own more conservative and safer standards, which leaves ordinary people with very few options if they determine they are subject to a higher-than-desired exposure. As noted, many scientists dissent from the federal exposure standards, given newer studies which demonstrate clear biological effects at lower exposures, and also because some people are more sensitive than others, which is not taken into account in the setting of the government standards which rely upon a non-existent "average person" given an "average exposure". Our feeling is, for long-term health and safety, one should reduce to as low as practically possible one's long term exposures to all forms of unnatural electromagnetic frequencies. A very short exposure at high levels is probably not going to do the average person any harm, but chronic exposure to significant low-level EM fields, as during sleep or while at work, is risky-business in our opinion.
For comparison, maximum allowable exposure for any public areas or microwaves as from Cell Phones and Towers, are 10 microwatts/cm2 for continuous exposures, or 580 microwatts/cm2 for short-term exposures. These are levels we personally feel are at minimum, 1000 times higher than should be allowed near to any residential neighborhood or school, much less for workers putting in 40 hours a week under such exposures. Typical city background (over a mile from any major transmitter) is around 0.100 microwatts/cm2. Typical background in the countryside near to a larger city is 0.010 microwatts/cm2 or less. At our rural facility in the Oregon mountains, several hundred miles from any major city, we have an exposure typically at 0.002 microwatts/cm2, which is very low and close to the calibration limits of the instrument. But when we drive into the nearby town, even there the levels climb to around 0.100 with occasional spikes to much higher levels. If we were to move back into town, then we would surely wish to find a place to work and live that was exposed to the lowest possible levels. Our opinions, however, do not carry any weight as regarding the legal issues involved, and representatives from the cell-phone companies will try to calm everyone into accepting the too-high federal standard of 10 to 580 microwatts/cm2. There are scientists who would agree with us, that this is too high a level, and others who will disagree. We cannot recommend to anyone what they "should do" or "shouldn't do" in the case of a particular exposure. But what we do recommend is that people measure what their exposures are, and then educate themselves and make educated decisions.
Natural Energy Works also carries several excellent books on these subjects,here.
Families Against Dangerous Electronic Radiation
Powerwatch
MastVictims.Org: A website dedicated to an international community of people suffering adverse health effects from cellphone masts in the vicinity of their homes.
Mobilfunk-Newsletter - EMF-Omega-News
WEEP Initiative: The Canadian Initiative to stop Wireless Electrical and Electromagnetic Pollution.
Vomiting and Diarrhea Plague Japanese Kindergartens
Reported Biological Effects From Radiofrequency Non-Ionizing Radiation
Microwave And Radiofrequency Radiation Exposure: A Growing Environmental Health Crisis?
The Effects of Wireless Communication Signals on Self-reported Symptom and Sleep (EEG)
Knesset bans placing cellular antennas on residential buildings
UK Powerwatch News Warning on Chilren Using Cell Phones
Health Effects from Cell Phone Tower Radiation
Electromagnetic radiation and health risks: cell phones and microwave radiation in New Zealand.
Radiation Poisoning of America
Health Effects of Microwave Radiation
Cell Phone Convenience or 21st Century Plague?
Cell Phone Radiation Poses a Serious Biologic Health Risk
Cell Phone Radiation - Maximum Exposure Levels
One could easily find dozens of similar articles by a simple internet search. Clearly, there is a growing concern for people who live or work close to cell phone towers and antennas, irrespective of whatever soothing words are spoken by the cell-phone companies and federal government agencies.
What we recommend, is to use the RF meter to measure a base-line determination somewhere outside your field of anticipated exposure, such as out in the countryside away from towns or facilities, to see how much is occurring by nature or only by exposures from a great distance. Then compare that to your home or workplace. If you face a problem such as exposure from a cell phone antenna on the roof of your building, or from an adjacent building, we suggest to make measurements away from all the buildings and antennas, then at the ground floor level, and progressively upwards until you are in the rooms of the apartment with the possible high exposure, both near to the windows and out on any balcony. You will then be in a position to judge for yourself, what kinds of unnatural exposures you may be subject to, and make informed decisions.
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