Holiday Sale at LessEMF.com
Great Gift Ideas for the Holidays
GaussMaster
EMF Meter with Sound
This little meter measures the level of ELF magnetic field radiation from power lines, computers, kitchen appliances, and more! The easy to read scale, unique built-in audio signal and auto shut-off make it simple to use and a great way to find hidden sources of ELF frequency magnetic fields.
Most experts agree that chronic exposure to more than 2.5 milli-Gauss is inadvisable. This meter will show you which areas are above or below 2.5 milli-Gauss in the 50 - 60 Hz frequency range.
Hand-held, lightweight and durable, with two easy to read scales (0-1 mG, & 0-10 mG), and dramatic audio signal. Our favorite meter for demonstrating the presence of dangerous EMFs to others and paranormal work. Requires one 9V battery (not included). Calibrated at 50-60 Hz.
Cat. #E130 ... Reg. $35.95
Now only $30.00!
Peak/Hold Gaussmeter
PEAK finds Worst Case EMF Exposure
Nice versatility in a low cost 1-axis meter. Comfortable in the hand and easy to read large digital 3˝ display. Peak feature allows user to let the meter run over extended periods to identify “worst case” fields. Hold feature will hold current readout. Can also be used in normal mode to make real time measurements.
•Sampling rate: 2.5 times per second
•Max Hold and Data Hold
•Uses standard 9V battery (included)
Cat. #E425 ... Reg. $89.95
Now only $79.95!
Click any item for more information on how to measure EMF:
To measure AC Magnetic Fields (what some people mean when they say "EMF"), from powerlines, wiring, lighting and appliances we use a gaussmeter. Gauss meters measure the strength of the magnetic field at the location of the meter. Because magnetic fields are oriented in space, the position of the meter will affect the reading (see discussion of 1 axis vs. 3-axis meters). Gaussmeters, also called Teslameters, can also be used to locate the source of a field, and to measure the performance of magnetic shielding.
The main features to consider when choosing a gauss meter are:
- Readout type: lights, sound, numbers, needle gauge
- Range: how sensitive on the low end, and the upper limit on the high end
- Axis: 1-axis only, 3-axis only, switchable 1-axis and 3-axis
- Accuracy: While high accuracy is desirable, it is not often necessary for locating "hot spots".
- Outputs: voltage output or PC interface for data logging
- Frequency weighting: see the short video on frequency weighting.
More Great Choices... Click below to order or more information
Rugged, Compact, & Lightweight Magnetic Field Meter
In our opinion, this is one of the best EMF meter values around. Couldn't be easier to use, just turn it on and get accurate reliable readings. Perfect for situations needing high resolution measurements of AC magnetic fields without spending a lot of money. Large LCD display reads 0.1 -199.9 mG over the ELF range of 30 - 400 Hz. Provides readout in both mG and microTesla. Calibrated to within 4% ±3 digits at 50/60 Hz. This single axis meter samples every 0.4 seconds when flipped on with slide switch. Requires one 9V battery. One year limited warrantee.
Like all single axis meters, this meter must be rotated during use to find the proper orientation to the magnetic field being measured to get proper readings.
Axis
Range
Resolution
Frequency
Accuracy
1
0-199.9 mG 0-19.99 microT
0.1 0.01
30 - 300 Hz
4% ±3 digits at 50/60 Hz
What is unique about this meter? Lowest cost digital gaussmeter, good accuracy & range, toggle mG/microT
Single Axis Digital Gauss/Tesla Meter (Cat. #A111) ..... $79.95
With the push of a button, this simple and accurate gaussmeter measures the level of
magnetic field emitted by all common electrical appliances and equipment. An easy to read
10 LED light bar scale gives readings from 1.5 to 30 mG in small increments. The
ElectroSensor has a detection range of 50-60 Hz with an accuracy of ±3dB. A pickup coil
in the tip of the unit can be rotated for increased directionality. EMF risk can be avoided if
you know where it is. If you are looking for a low cost, user-friendly meter, here it is!
AAA battery included.
Axis
Range
Resolution
Accuracy
1
0-30 mG
1 of 10 LED
±3dB
What is unique about this meter? 10 LED resolution, smallest gaussmeter, very simple operation
LED 10
LED 9
LED 8
LED 7
LED 6
LED 5
LED 4
LED 3
LED 2
LED 1
This little meter measures the level of ELF magnetic field radiation from power lines, computers, kitchen appliances, and more! The easy to read scale, unique built-in audio signal and auto shut-off make it simple to use and a great way to find hidden sources of ELF frequency magnetic fields.
Most experts agree that chronic exposure to more than 2.5 milli-Gauss is inadvisable. This meter will show you which areas are above or below 2.5 milli-Gauss in the 50 - 60 Hz frequency range.
Hand-held, lightweight and durable, with two easy to read scales (0-1 mG, & 0-10 mG), and dramatic audio signal. Our favorite meter for demonstrating the presence of dangerous EMFs to others and paranormal work. Requires one 9V battery (not included). Calibrated at 50-60 Hz.
Axis
Range
Resolution
Frequency
Accuracy
1
0-1 mG 0-10 mG
0.1 mG 1 mG
50/60+ Hz
no spec
What is unique about this meter? Lightning fast needle response, audio function
Includes nice instructions on how to perform a proper survey of your home, office, or school yard.
"I tested it on several items and was surprised how much some things registered. My electric blanket registered extremely high so now I will warm up the bed and turn it off once I go to bed. My clock radio that's about a foot from my head was so high I unplugged it."
P.K., Helena, AL
Want to make modifications to your GaussMaster?
Here is a link to a site showing how to add switches, amplifiers, outputs and more to your GaussMaster to make it even more useful.
Here is another for external antenna jack modification Warning: these sites are not affiliated with Less EMF We do not vouche for their accuracy, and provide this information only for your enjoyment. Proceed with caution as modifying your meter will void the warranty.
Nice versatility in a low cost 1-axis meter. Comfortable in the hand and easy to read large digital 3˝ display. Peak feature allows user to let the meter run over extended periods to identify “worst case” fields. Hold feature will hold current readout. Can also be used in normal mode to make real time measurements.
Axis
Range
Resolution
Frequency
Accuracy
1
0-200.0 mG
0.1
30 - 400 Hz
3% ±3 digits at 50/60 Hz
What is unique about this meter? Peak/Hold function
This EMF tester is designed to provide user a quick, reliable and easy way to measure magnetic field levels around power lines, electrical appliances, wiring and industrial devices. Probe head measures 2.7 * 2.3 * 2.8 inches.
- One button scrolls through X, Y, and Z axis readings
- Wide measuring ranges (3 ranges of µTesla and 3 ranges of mGauss)
- Big digit LCD display
- Data hold button
- Simple to operate, uses 1 9-volt battery
- Easy to use remote probe, fits hard-to-reach spaces
Unit
Range
Resolution
Accuracy
Axis
Frequency
µTesla
20
0.01
±(4% + 3d)
1 toggle: X,Y, or Z
30 Hz to 300 Hz
200
0.1
±(5% + 3d)
2000
1
±(10% + 5d)
mGauss
200
0.1
±(4% + 3d)
2000
1
±(5% + 3d)
20,000
10
±(10% + 5d)
What is unique about this meter? External probe, scroll X,Y, Z axes, wide range up to 20 G!
Complete with 3ft (930mm) sensor cable, and hard carrying case. 1 year warranty.
True-RMS 3 Axis AC Gaussmeter with all the features you could want. A real technological breakthrough.
Axis
Range
Resolution
Frequency
Accuracy
3
0-250 mG 0-25.0 microT
0.01 mG 0.1 microT
15-5500 Hz
±˝dB 30 to 5000 Hz
What is unique about this meter? Backlit, peak/hold function, toggle mG/microT, toggle all axes
Flat frequency response:
±˝dB 30 to 5000 Hz
-3dB 15 to 5500 Hz
Selectable axis (3D, X, Y, Z) on ALL features
Peak Axis (which axis has the strongest field)
On-Screen Graphing (Horizontal bargraph of field strength)
Max Hold
Variable Brightness Blue LED Backlight
Selectable units: milliGauss or microTesla
Fast Update Rate: 2.5 times per second
Low battery indicator
Alkaline battery (included) typically lasts ~15 hours at default backlight setting. Suitable for general purpose magnetic field readings, and great for paranormal work as well. Lowest price for a 3 axis digital gaussmeter! 1 year wty. Made in USA.
Compact and easy to use, this digital unit can measure ELF (13 Hz to 1 kHz) and/or VLF (1 to 75 kHz) magnetic fields in either single axis mode (to help identify the orientation of the field) or 3-axis mode (which makes routine measurements much faster and more reliable). Range from 0.01 mG to 1999 mG. 5˝ digit display. 3% accuracy from 45 to 5000 Hz but useful from 13 Hz to 75 kHz. Very simple: One knob selects from these 3 modes: 3-axis ELF+VLF, 3-axis VLF, 1-axis ELF+VLF. Uses standard 9V battery (included). Made in USA. One year mfr warranty.
Axis
Range
Resolution
Frequency
Accuracy
1 or 3
0-1999 mG
0.01 mG
13-75k Hz
3% from 45 to 5000 Hz
What is unique about this meter? Distinguish ELF from VLF signals, wide frequency range
In paranormal research, the presence of man-made 50 or 60 Hz EMF signals can give rise to "false" readings. Wouldn't it be great if you could set your EMF meter to ignore these ever-present signals and just pick up everything else? Now you can! With this meter you can look at just the 50/60 Hz signal, or just the harmonics, or just everything else. And you can compare that reading to the overall reading on the same screen at the same time! Adjustable back light too, because it was designed with paranormal research in mind.
Also perfect as an all purpose True-RMS 3-Axis meter with high sensitivity. Great for distinguishing a 50 or 60 Hz signal from the higher frequency harmonic signals which often accompany power line magnetic fields.
Axis
Range
Resolution
Frequency
Accuracy
1 or 3
0-250 mG
0.01 mG
15-5500 Hz
±˝dB 30 to 300 Hz
What is unique about this meter? 3-axis Backlit, peak/hold function, toggle mG/microT, toggle all axes
More Features:
Flat frequency response:
±˝dB 30 to 300 Hz
Selectable axis (3D, X, Y, Z) on ALL features
Two display styles:
On-Screen Graph: select any of 3 values: total RMS, notched, bandpassed
Digital readout: RMS broadband plus select:
60Hz only, or 60Hz+Harmonics, or 50Hz, or 50Hz+Harmonics
Variable Brightness Blue LED Backlight
Max Hold of any of the 3 values
Selectable units: milliGauss or microTesla
Low battery indicator
Alkaline battery (included) typically lasts ~20 hours at default backlight setting. Feature rich and easy to use, same meter works for both 50 or 60 Hz. Great price too! 1 year wty. Made in USA.
Magnetic Field Dosimeter with Tremendous Capability and Versatility
We are really excited about this new meter designed to provide quick, reliable and
easy measurements of electromagnetic field radiation levels around power lines, home appliances and industrial devices. Displays 3-axis microTesla or milliGauss readout with date/time; offers Data Hold & MAX/MIN Hold functions. Extremely sensitive with range all the way up to 1999 mG. Want more? Toggle between 3-axis sum or show each X, Y, Z value. Data-logging capacity with time/date stamp for field use and USB interface, Windows 98/2000/XP/7 software and cable included. Large, easy to see display and rugged meter body. Uses one 9V battery. Great price too!
SPECIFICATIONS
Display
4 digits. Max. indication 1999
Auto Range
20/2000 milli Gauss 2/20/200
micro Tesla
Resolution
0.01/1 milli Gauss 0.001/0.01/0.1
micro Tesla
Number of Axis
Three axis
Band Width
30 Hz to 2000 Hz
Accuracy
±(3%+30d) at 50/60Hz at 20 mG; ±1mG below 2 mG
Datalogger storage
9999 manual readings
Sampling Time
2.5 per second
Accessories Included
Operation Manual, 9V battery, Software for Windows and USB Cable, padded case
What is unique about this meter? Data logging and PC interface, low cost
A useful and reasonably priced meter for measuring both AC and DC magnetic fields. Easy to use with external single axis probe. Excellent range with great features including:
DC and AC (40 Hz to 10 KHz) magnetic field measurement
High sensitivity: down to 0.1 mG
High range: up to 3000 mG
Accuracy: ±(2% + 2 mG)
N pole/S pole indicator
Reads in mG or µT (toggle)
Zero adjustment button (tare) for relative measurement
Data hold function for freezing the current value on display
Records Maximum and Minimum readings with Recall
1 second sampling time
3.5 mm data output jack
What is unique about this meter? Measures both AC and DC magnetic fields
Uses 6 AAA batteries (not included). Can also be power by external DC 9V adapter (sold separately).
A practical guide for reducing AC magnetic fields produced by building wiring and improper grounding practices. Step by step instructions for detecting wiring problems and a full description of common wiring errors and how to correct them. This guide is for anyone who wants to inspect their own home, electricians and electrical inspectors, those starting a new profession in EMF consulting, as well as those involved with the process of building construction such as architects and contractors. Utility personnel involved in EMF measurements can profit from this information. 96 pages, spiral bound book. Completely updated in 2012.
Typical Applications include checking the 50 and 60 Hz magnetic fields produced by such equipment as transmission lines, computers, electric blankets, electric appliances, televisions, etc. Very high accuracy and sensitivity. Made in USA by INTEGRITY DESIGN.
Specifications:
Portable, digital readout
Auditory and visual Alarm
Remarkable Linearity
Narrow Bandpass Filter
Sturdy Shielded and Grounded Probe
200 mV recorder Output
Range Settings: 2, 20, 200, 2000 milliGauss
Bandwidth: 11 hertz at 3db
Battery life: at least 48 hours with one 9v alkaline battery included
Weight: 15 oz. (425 grams)
Sensor: External Air coil type with 8" handle
Very high accuracy: 1% maximum error based on EPA report
What this meter lacks in resolution it makes up with ease of use and very low cost. Will measure ELF/VLF magnetic fields in the frequency range of 20 - 10,000 Hz, with a minimum sensitivity of .25 mG. Laboratory tested and documented for accuracy.
Three LED lights signal field strength:
0 - 2.5 mG ("safe")
2.5 - 7 mG ("caution")
8 or more mG ("danger")
Axis
Range
Resolution
Frequency Response
Accuracy
1
0.25 to 8+ mG
1 of 3 LEDs
20 to 10k Hz
no spec
What is unique about this meter? Lowest cost gaussmeter available
Single axis sensor, on/off toggle switch. One fresh 9V battery required. Useful for preliminary surveys of home, car, or office. Very popular for paranormal work too!
Common ELF magnetic field frequencies are within the range of human hearing. This simple set up converts the AC magnetic signal directly into a dramatic corresponding sound signal. A 60 Hz powerline field sounds like a 60 Hz hum (a low note on piano keyboard). Harmonics can easily be heard, as well as clicks, static, and hash. LED displays are especially noisy. The strength of the field is proportional to loudness.
Unit includes a single axis probe on 2 foot cable and audio amplifier. You can even use an optional earphone/headset for discreet operation. Use it to “sniff out” sources of interference, offending EMF, check shielding designs. Makes a great educational tool. Requires one 9V battery.
Completely Unique! Hear the VLF Signals in your Vicinity!
VLF signals (kHz range) occur naturally and can be produced by lightning, solar flares, and aurora. They can also be man-made, emitting from smart meters, solar power inverters, dimmer switches, motors, and fluorescent lights.
Use this portable VLF band radio to listen to the natural sounds of the earth. Lightning, whistlers, tweaks and auroral chorus can be heard from more than 3200km on the built in speaker or by using the included ear buds. Sounds can be recorded directly to a computer for analysis or future playback. Perfect for creative listening, storm chasers, researchers and paranormal investigators. It’s like a buzz stick for dirty electricity as well.
A high quality audio chip set gives the best sound experience possible. The revolutionary loop antenna allows the unit to be truly portable for field work, or for instant listening pleasure in the home. Separate controls for receiver power and audio volume allow for optimal adjustment to any application. An audio output jack allows for the use of headphones, connection to a computer audio line-in or sophisticated recording devices such as oscilloscopes and data acquisition systems. For long term recording, an external power adapter connection is provided.
Covers 600 Hz to 35 kHz, very intuitive and extremely simple to use. Great for demonstrating the benefits of dirty electricity filters. There is nothing else like it!
Equipment Set-Up for Analyzing Frequencies from 0-60 Hz
Analyzing frequency information from ultra-low frequency magnetic fields can be extremely challenging. Air coil type magnetic field probes just don't have the necessary sensitivity below about 20 Hz.
The voltage output from our Geomagnetometer (read more) provides excellent frequency information from low frequency signals. The amplified, unrectified, Hall effect probe output retains all the frequency information from the magnetic field under investigation.
Simply connect the voltage output (3.5mm mono jack) from the Geomagnetometer to the oscilloscope or spectrum analyzer and monitor both field strength AND waveform, frequency, and spectrum distribution of your signals. Because the Geomagnetometer output produces 200 mV at full scale, you get plenty of signal to the oscilloscope or spectrum analyzer.
For example, on the 0-2 mG range: 2 mG produces 200 mV output, .05 mG produces 5 mV. On the 0-200 mG range: 200 mG produces 200 mV output, 5 mG produces 5 mV.
In our tests, the actual output range from the Geomagnetomer extends significantly beyond 200 mV, and was useful up to 60 Hz and beyond. Interested in .01 Hz? 2 Hz? 7.8 Hz? No problem! You can analyze fluctuations in the Earth's magnetic field, fields from audio recordings, and almost any other ultra-low frequency magnetic field source. Possibly biologic and paranormal sources?
Connect your computer to this meter's output to make a spectrum analyzer (with optional PC Based Oscilloscope)! You can even add the Audio Amplifier to boost weak signals.
Individual Components:
Geomagnetometer only (Cat. #A3100) ............................................ $750.00
To connect Geomagnetomer to your PC, you will need:
6 foot 3.5 to 3.5 mm mono plug cable only (Cat. #A134-cable) ......... $4.95
Zero Gauss Chamber
This chamber can be used with the Geomagnetometer to provide a zero gauss (magnetic field-free environment) reference, enabling you to take absolute readings of the ambient magnetic field (the Earth's magnetic field is typically around 500 mG). Concentric welded 12" long tubes (1" ID chamber) with stand, made of high permeability magnetic shielding alloy provide excellent shielding.
Zero Gauss Chamber (Cat. #A3105) ......... $395.00
9V alkaline battery included & DC adaptor, Hard case is included
Two year parts and labor warranty, made in USA
Typical Applications include checking the frequencies and magnetic fields produced by such equipment as computer monitors, television sets, power lines, induction heaters, industrial, scientific and medical equipment and electric appliances, etc.
Truly unique. You get 3-axis VLF readout with simultaneous frequency indication (1-200 kHz), peak hold, alarm, datalogging, and RS-232 connection. Wow! Portable and easy to use. Covers 0.2 – 2000 mG in 2 ranges.
Typical applications include checking the frequencies and magnetic fields produced by such equipment as computer monitors, television sets, video display terminals, induction heaters, industrial, scientific and medical equipment and ground wave energy network. Hard case, 9V alkaline battery & DC adaptor included. Two year parts and labor warranty. Made in the USA
Qi Wireless Charging
Qi wireless charging uses inductive power transfer in the 110-205 kHz range. This frequency is emitted from the charging station and can be detected in its vicinity. This VLF 3-axis Gaussmeter is an excellent choice for measuring this emission.
Specifications:
Frequency response: 1-200 kHz
Analog output for X, Y and Z axis waveform
Predominant frequency indicator for each channel
Isotropic sensor… Switchable to single axis mode
True RMS measurement with peak hold
Error ±3% maximum
16 character x 2 line display
Sensor: External three Axis X, Y, Z Air coils type with 8" handle
Sensor dimensions: 1.9" diameter, 3.3" length
Datalogging up to 32,000 data points, adjustable interval
Datalogging interval adjustable from 1 ms to 9999 s (software not included)
Record data of all channels to PC via RS-232 communication port
These passive magnetic field sensors output AC voltage corresponding to the AC magnetic field strength. The frequency of the AC output voltage is the same as the frequency of the magnetic field. Single-axis, so it responds to fields parallel to the sensor axis. The sensor orientation shows the magnetic field polarization. No battery or power supply is needed.
Connect to a display instrument (not included) such as AC voltmeter, oscilloscope or spectrum analyzer to display the output AC voltage and waveform information. These sensors have no minimum measurable field strength, so the sensitivity will depend on your display instrument. Maximum field: the sensor can be damaged above approximately 50 Volts output. Sensor includes operating instructions.
Frequency Range:
For 5 kHz - 1 MHz, the sensor output voltage is at least 70% of the magnetic field strength in Gauss (Volts/Gauss > 0.7). Sensors can also be used below this frequency range, but will have lower output voltage.
Calibration:
Each individual sensor is tested and recorded to ensure NIST traceable accuracy. Individual calibration data table is delivered with each sensor.
Rectangular 1"x1"x0.8" and has a BNC (female) output connector on the case. Weighs only 1 oz (30 g).
VLF Magnetic Probe (Cat. #A180) .......... $150.00
Bonus!
Use your computer with this probe to make an VLF spectrum analyzer (with optional PC Based Oscilloscope)! This has to be the lowest cost way to get high quality frequency information about your magnetic fields. Explore the mixture of frequencies commonly associated with common household sources, demonstrate harmonics, even compare shielding effects at various frequencies.
Three foot long cable, BNC to BNC with removable dual bana jack.
BNC to Dual Banana Cable (Cat. #A128) ............. $14.95
So what magnetic fields do you want to measaure? AC? DC? Need frequency information too? This meter does all that and more. Simlutaneous digital readout of field strength and predominate frequency, true RMS measurement with peak hold, One volt full scale analog voltage output, alarm, dataloging up to 32,000 data points, and 3 % error guarantee. External probe.
Operate in 1 of 3 modes:
3 Ranges:
DC only
300 G (100 mG resolution)
AC only: 20 Hz - 1 kHz
3 kG (1 G resolution)
AC + DC: 0 – 1 kHz
30 kG (10 G resolution)
Completely portable. 4 AA alkaline batteries included and optional 6V DC adaptor available. Choose axial probe, transverse probe, or both. Zero gauss chamber (included ) helps when zero-ing the unit.
This chamber can be used with the DC/AC Gaussmeter to provide a zero gauss (magnetic field-free environment) reference, enabling you to take absolute readings of the ambient magnetic field (the Earth's magnetic field is typically around 500 mG). Concentric welded 12" long tubes (1" ID chamber) with stand, made of high permeability magnetic shielding alloy provide excellent shielding.
Zero Gauss Chamber (Cat. #A3105) ......... $395.00
Perfect for meters, instruments or cameras. Fits plenty of stuff in a compact space. This rugged case features aluminum trim, riveted corners, lock and keys, carry handle and metal hinges. Black hard sidewalls. Black padded inside walls but no foam. Outside: 12'' x 10'' x 4''; Inside: 11" x 9¼" x 3¼".
You can also use it to store:
important papers
seeds
toiletries
knitting / sewing supplies
crayons / chalk
photos
coupons
medicines / vitamins / homeopathy
hand gun / ammo
tools
collectibles
art / craft supplies
cash / valuables
diary
love letters
small toys, Legos, puzzles
business cards
lunch
receipts
baseball cards
Deluxe Instrument Case (Cat. #A711) .............................................. $19.95
Need batteries? Factory fresh, name brand, low price alkaline 9V batteries. Brand may vary. No fancy package, just fresh batteries, cheap. No limit.
Alkaline 9V Battery (Cat. #A787) …................. $1.95
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. 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 that its single axis counterpart. See 3-Axis Digital Gaussmeter and Trifield Meter for examples of 3-axis gaussmeters.
See lots more information on our FAQ page. (Frequently Asked Questions)
Can't decide which meter is right for you? Click for a handy Meter Selection Guide to learn how to choose a meter to measure EMF
Holiday Sale at LessEMF.com
3-Axis Backlight Gaussmeter (Cat. #A107) … $269.00 
3rd edition, by Karl Riley.
Very High Accuracy and Sensitivity
Common ELF magnetic field frequencies are within the range of human hearing. This simple set up converts the AC magnetic signal directly into a dramatic corresponding sound signal. A 60 Hz powerline field sounds like a 60 Hz hum (a low note on piano keyboard). Harmonics can easily be heard, as well as clicks, static, and hash. LED displays are especially noisy. The strength of the field is proportional to loudness.
Analyzing frequency information from ultra-low frequency magnetic fields can be extremely challenging. Air coil type magnetic field probes just don't have the necessary sensitivity below about 20 Hz.
This chamber can be used with the Geomagnetometer to provide a zero gauss (magnetic field-free environment) reference, enabling you to take absolute readings of the ambient magnetic field (the Earth's magnetic field is typically around 500 mG). Concentric welded 12" long tubes (1" ID chamber) with stand, made of high permeability magnetic shielding alloy provide excellent shielding.
5 kHz - 1 MHz
