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 Meter FAQs

- Where do I begin?
- What is the real difference between a single axis and a triple axis gaussmeter?
- Why do the readings on two different RF meters not match?
- I have found strong readings on my meter. How do I find the source of these fields?
- How do I measure a cell tower??
- How do I measure the radiation from my cell phone?
- What units should I use to measure RF?
- I want to do paranormal research. Which meters are appropriate?
- I think I am being electromagnetically harassed. What equipment do I need?
- At what distance from a source of field can I use a meter?

Where do I begin?

Where do I begin?

If you are the type of person who likes to know everything about a subject before you begin your journey, you have a long road ahead of you. Here is some practical advice for the beginner that will help you get started immediately, and lead you towards effective solutions right away.

Diagnose your EMF exposure

1. Diagnose your EMF exposure

Please don’t call and ask us how much exposure you are getting from your TV, toaster, iPad or any other device. We cannot know the answer to this question. First of all, you will find that emissions vary from model to model, that they vary with distance, and that they vary over time (Is the device plugged in? Is it turned on? Is it running? Is it on the high setting? Is it charging? Etc. etc.) In addition, your total exposure is the sum of exposure from ALL sources in your vicinity. It is possible that the majority of your exposure is coming from a source different from what you think it is (Is the refrigerator next to the toaster? Is there wiring under the floor that you don’t know about? Is there a TV on the opposite side of the wall? Etc, etc.)

You must determine your exposure with a meter. Period.

Get a meter and begin by making measurements where the people are. It doesn’t matter if there are high levels where there are no people. Check your bed, your couch, your car, your kitchen. Check the areas where you spend time. And take your meter with you throughout the day to make measurements while you are actually doing your activities. (There could be a big difference between day versus night levels in your bedroom, in your kitchen when the stove is on versus the microwave, or in your bathroom when the fan, hairdryer or heat lamp is on.)

Here are our recommendations for simple, economical meters to begin with:

Low frequency EMF (from the presence of electricity):
  Trifield Meter
  Digital Combination meter

High frequency (radiowaves, microwaves, wireless signals):
  High frequency meter
  3 Axis RF meter

Dirty electricity (high frequency signals on the wiring):
  Stetzerizer meter
  Line noise meter

Body Voltage (voltage induced in the body from exposure to EMF):
  Body Voltage meter

podcast featuring Emil DeToffol

If you find high levels where the people are, the only next step is to determine the source(s) for these high levels. Use your meter to sweep the area, sweep the walls, floor, ceiling and the objects in the room. As you get closer to the source, the EMF levels will increase. If necessary, unplug or use switches and circuit breakers to turn on/off certain things to see if that is where the trouble originates.

2. Mitigate the worst situation first

Once you have determined the sources of EMF in your environment, pick one… usually the worst one… to take care of first. It's tempting to start with the easiest problem, but common sense and experience tells us to start with the worst problem first. Then move on to the next most urgent problem. Most importantly, take SOME action. For any given source, consider all of the following:

Use distance to reduce exposure
Can I move the EMF source(s) away from the people? (Move the refrigerator to the garage or basement. Alarm clocks do not need to right next to the person, neither do printers, modems, TV’s, refrigerators, etc.)
Can I identify areas of low exposure and move the people to those areas? (Examples: Move the bed to another part of the room. Rope off a safe distance to a hot spot. Put a book case or closet over a hot spot to keep people away.)
Move if necessary. Mitigate the worst situation first

Get rid of EMF sources
Replace dimmer switches with flip switches.
Replace halogen, LED, and fluorescent lights with incandescent ones.
Instead of wifi, run cable.
Use a towel instead of a hairdryer.
Ask yourself, “Do I really need a microwave oven, google glasses, electric pencil sharpener, etc.?”
Use timers so devices don’t run when you are near them.
Install switches so you can easily turn off circuits or individual devices.
Select low EMF alternatives.

Install shielding
Use magnetic shielding in your car.
Wear shielded clothing.
Sleep under a shielded canopy.
Make a shield to slide over your blender when in use.
Shield your walls and windows, smart meter, breaker box, laptop, etc.
Contact us, we can give specific shielding advice for your circumstances.

Why do the readings on two different RF meters not match?

There are several reasons why two different models of RF meter will give a different reading. In the real world, it is rare to encounter a single signal. Generally, a wide mixture of signals from multiple sources will be present. These signals will have different frequencies, different orientations, and different digital characteristics. How a meter interprets these differing aspects will impact the readout.

1] Frequency range

Frequency range?
Every meter has a specified frequency range. 30 MHz to 2.5 GHz, for example. The meter can be expected to detect and report signals within that range. Signals which are outside of that range may be detected only weakly, or not at all. So if a signal is present which is within the range meter “A”, and outside the range of meter “B”, it will only show up on meter “A”.

2] Frequency response

Frequency response?
The size and shape of an antenna will influence how well it receives a signal of any given frequency. For every antenna, there will be frequencies that it picks up better than others even within the specified frequency range of the meter. Imagine listening to a marching band. If your hearing is better for the high notes of the piccolo, or the low notes of the tuba, your experience of the same performance will be different than that of the person standing next to you.

3] Same time and place

Same time and place
If you have taken RF readings, you know that the levels can fluctuate widely from one moment to the next and from one location to the next. Even moving the meter a few inches to one side or another can have a large impact. It is difficult to place two meters in the same location at the same moment, so part of the difference in readings is due to this time and location difference.

4] Orientation of the signal

Orientation of the signal
All RF signals have an orientation in space. They may be vertically or horizontally polarized, they may be circularly polarized. The orientation of the meter’s antenna relative to the signal will greatly impact the meter’s ability to “see” the signal. If the antenna is aligned properly, it will see the signal. If it is not, the readout will be lower . When multiple signals are present (with different orientations), it is difficult to define the “proper” antenna orientation.

In addition, signals may be originating from different locations. So, for example, one signal may be coming from the North, another from the East. The direction that the meter is pointed will impact how well the meter “sees” a given signal. If pointed to the North, it will see that signal very well, but could miss the signal from the East entirely.

Further, it is possible that the user’s body may partially shield a signal coming from behind, reducing the meter’s ability to detect it. Also, objects nearby may be reflecting some signals, so that not only is the primary signal reaching the meter, but signals reflected from nearby objects could increase the amount of radiation reaching given spot.

5] Peak vs. Average

Peak vs. Average?
Most signals today are digital. Digital signals are composed of a series of short bursts separated by periods of quiet, almost like a barcode. It is possible to define the strength of the signal by reporting the peak intensity (the strongest burst within a specified time) or the average intensity (the average of all peaks plus quiet periods within a specified time). This creates three possible discrepancies between different meters:
a) What is the specified time? Different sample times will yield different results.
b) Is the meter reporting peak or average? Some meters do not specify.
c) Is the meter reporting some combination of peak and average?

6] Sensitivity

Every meter will have both an upper and lower limit of the strength of the signals it can measure. Some meters will be more sensitive than others on the low end, meaning they can detect weaker signals.

Taking all this together, it is a wonder we can measure RF signals at all! In truth, no meter detects all the signals which reach its location, for the reasons listed above. It comes down to how much of the signal present does the meter capture and how much does it not capture. As you can see, part of the answer depends on the characteristics of the meter, and part depends on the orientation and characteristics of the signal.

What is the real difference between a single axis and a triple axis gaussmeter?

Because magnetic fields are oriented in space, a sensor will only detect the field properly if it is aligned with the field. A single axis meter has only one sensor in it. Therefore to get a correct reading with this type of meter, you must slowly rotate the meter until you find the maximum reading. This will be the correct reading. If the meter is turned 90° from the maximum reading, it will read nearly zero. See Single Axis Digital Gauss Meter for an example of a 1-axis gaussmeter. It is easy to understand how it is possible to get a lower than actual reading if the meter is not properly aligned.

A three axis meter has 3 sensors in it, all aligned at right angles to each other. Therefore, this type of meter is always correctly aligned and no rotation is required to get a correct reading. This type of meter takes less time to use but generally costs more than its single axis counterpart. See 3-Axis Digital Gaussmeter and Trifield Meter for examples of 3-axis gaussmeters.

I have found strong readings on my meter. How do I find the source of these fields?

Whether is it electric fields, magnetic fields, or radiowaves, the source of the field will always be in the direction of the strongest signal. It is critically important to avoid being fooled by thinking that the meter points in the direction of the source.

Field Lines A perfect example of this phenomenon involves powerlines. You should remember that the direction of magnetic field lines around a current carrying wire is circularly perpendicular to the wire. So alongside the wire, the field lines are vertical, while underneath the wire, the field lines are horizontal. The proper orientation of a single axis meter may point the meter at the wire, or straight up and down, or even horizontal, depending on the orientation of the sensor in the meter and the position of the meter relative to the wire. Furthermore, the orientation of a 3-axis meter is irrelevant to the reading, so it could be pointing in virtually any direction and still give a correct reading.

Only by moving the meter bodily toward, then away, from a suspected source can one determine the location of the source.

Cell Tower

How do I measure a cell tower?

There is much concern about the health effects resulting from microwave radiation from cell tower and radio antennas. Biological effects have been clearly established at levels well below the government exposure limits. 3-axis RF Meter

However, people are often surprised to learn that the strength of the signal from a cell tower or radio antenna is extremely small if you are any distance at all from the antenna. At 100 yards, the signal strength is well below the sensitivity of most meters. In order to measure these signals, you need an extremely sensitive meter. You also need a meter which can accurately process a digital signal (which is different from an analog signal in the way it interacts with a meter), and it would be useful to have a meter which is directional, so that you can take a measurement of a specific tower, without interference from extraneous sources behind or to the side of you.

For these reasons, there is only one best meter we recommend for measuring antenna: HIGH FREQUENCY METER. It has the sensitivity (10 picoWatts/cm²) to measure an antenna miles away, process analog or digital signals correctly, and it'S antenna is directional.

Of the low cost meters, the Basic RF Meter may be useful in some circumstances. This device is somewhat directional and it is somewhat more sensitive than the other low cost RF meters.

The 3-axis RF Meter is probably the best pick for non-technical users. It is very easy to use, very sensitive ( down to 0.4 nanoWatt/cm²) and gives a calibrated, digital readout of field strength.

How do I measure the radiation from my cell phone?

Cell Phone

This is perhaps the trickiest measurement you are likely to attempt. The reasons include: Scan Probe

  • Because the phone is used directly against the head, the only valid measurement of cell phone radiation is close up to the phone. At cell phone frequencies, the NEAR FIELD is on the order of a few inches. Therefore measuring the field accurately within about 2 inches of the phone requires a NEAR FIELD probe. Most low cost meters are FAR FIELD meters.
  • Most cell phones today use digital signals. An analog meter may pick up some radiation, but it will never give a correct reading due to its inability to process the digital signal properly.

There are NEAR FIELD probes which can be connected to a spectrum analyzer for a cost of $30,000 or more. And of course, there are $100,000 SAR machines for doing SAR testing. But what can an ordinary person use to measure the output from his phone or check the effectiveness of a shield?

We recommend the 6 GHz RF Meter with Near Field Probe accessory. For about $240, you can use this NEAR FIELD meter to check all surfaces of your phone and establish where the hot spots are.

What units should I use to measure RF?

Units Comparison When measuring distance, you can use a variety of units: inches, centimeters, miles, fathoms, etc. Some units are larger than others. Some are more familiar than others. However, regardless of the units you use, the distance you measured remains constant but the number you get can vary widely.

Similarly, when measuring radiofrequency signal strength, many different units can be used. They are all equally valid*, and you can convert from one unit to another. But some units are much bigger than others.

You wouldn't measure the distance from Paris to Rome in inches; you would use a bigger unit... perhaps kilometers. Likewise, you would use a very small unit to measure the thickness of a human hair. So, when measuring the generally low levels of background RF radiation, you can use a small unit, such as V/m. When measuring the relatively large amount of radiation that leaks from a microwave oven, you can use a larger unit, such as mW/cm2.

The image shows the relative size of some units compared to 1 V/m. Notice that A/m is a much larger unit, almost 400 times the size of one V/m. A/m is better suited for measuring very strong radiation.

* Engineers will have a preference for one unit over another, particularly when measuring in the near field.

Paranormal Activity

I want to do paranormal research. Which meters are appropriate?

There are 3 main categories of meter that are popular among paranormal researchers:

AC Gaussmeters: The hands down favorite is the 3-axis Trifield Meter . With its fast reaction needle gauge and 2 sensitivity scales, this meter is so easy to use right out of the box. Other choices include the 3-Axis AC Gaussmeter for high accuracy, the Single Axis AC Gauss Meter for economy, and among the low cost single axis meters: GaussMaster offers an audio tone, and E.L.F. Zone offers lights which are very useful in the dark. Ghost Hunting Kit

Remote Temperature Scanner: The easiest way to check for cold spots is the Remote IR Thermometer. Complete with a laser pointer for good aim, simply point and shoot to get instant temperature readings of surfaces 10, 20 or 50 or more feet away.

Exotic Meters: Some researchers believe that paranormal activity can ionize the air. This phenomena is easy to measure with the Air Ion Counter. Radioactivity can be affordably checked with the Monitor 4. Changes in DC electric and magnetic fields can be picked up with the Natural EM Meter, which also offers an audio tone for low light conditions. A motion detector can be used to remotely detect moving objects, opening doors and windows, and the appearance of hot spots.

A great book on ghost hunting tools and techniques is Ultimate Ghost Tech by Vince Wilson.

I think I am being electromagnetically harassed. What equipment do I need?


This is a very tough question to answer. Harassment could take many forms: chemicals, ions, sound, microwaves (what frequency?), light, covert technologies, and so on. There is no one meter that can measure all these different phenomena. Furthermore, your symptoms may be due to something else altogether such as allergies, migraines, high blood pressure, or a thousand other conditions.

If you are serious about determining if you are being intentionally exposed to electromagnetic fields, then the logical place to start is with meters which offer the widest range of sensitivity.

One low cost possibility is the combination of the Trifield Extended Range Broadband Meter plus the Natural EM Meter will cover the whole range from DC to 2.5 GHz. This combination offers the ability to distinguish if the offending field is AC or DC, and whether it is electric, magnetic or microwave.

At what distance from a source of field can I use a meter
(that is, what is the range in distance of a meter)?

All meters have a range of exactly zero feet. This means that all gaussmeters, electric field meters, RF/microwave meters, etc. can only measure the strength of the field AT THE LOCATION OF THE METER.

What distinguishes one meter from another is the sensitivity. In other words, what is the smallest field strength that the meter can detect? A gaussmeter with a sensitivity of 0.1 mG is more sensitive than a meter which can only detect down to 1.3 mG. While the meter which is more sensitive can be successfully used further away from the source of the field, it is still only measuring the field at the location of the meter.

So the next question is: if you have a meter with a certain sensitivity, how far from a source of field is it useful? The answer to that depends on 3 factors:

  1. what is the strength of the field at the source?
  2. at what rate does the field decrease with distance (1/d, 1/d², 1/d³ etc.).
  3. what is the pattern of radiation from the source? (You may remember that the magnetic field is concentrated at the poles of a magnet. Some sources may have symmetrical field patterns, some may not.)

Without knowing a great deal about the nature of the source, it is impossible to determine at what distance a given meter will begin to detect its field. What you can do is easily compare the minimum sensitivity of one meter to another. This specification is given in the description of most meters.

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