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Seeing Is Believing

Viewer Card Finally, a way to actually "see" DC magnetic fields from permanent magnets or magnetized metals without messy iron filings! You can use this amazing film over and over to view the location and number of poles on any magnet. Just lay the card on the magnet to see the polar pattern. Magnetic poles appear as dark areas and the light areas represent where the N and S poles meet. A great inexpensive magnetic detector for finding objects in your environment that have become magnetized. Uses no batteries. Also great for science projects. Dimensions: 2-1/2" x 4"

Made in USA MAGNETIC VIEWER CARD (Cat. #A1120) .......... $2.75 add to cart
Case Price [50 units] (Cat. #A1120-case) ............... $123.50 add to cart

Viewer Gel

Magnetic Field Viewer Gel

Same flat viewer material that is in the viewer card but larger (full 12" x 12") and without the lamination. Can be re-used over and over. Can be cut to custom sizes with a scissors, bent or rolled. For DC magnetic fields only.

Paper-thin and highly flexible, this viewer uses micro-encapsulation of colloidal Nickel to reveal magnetize material. In the encapsulation process, colloidal Nickel particles suspended in the slurry become engulfed within gelatinous membranes. A 2-mil layer of the magnetically sensitive slurry is bonded to a 5-mil sheet of plastic film and allowed to dry. After complete drying, the particles maintain freedom of movement within the gelatinous membranes.

When a DC magnetic field is applied to the finished film, the Nickel particles congregate in alignment with the flux lines emanating from the DC magnetic source. This clumping of nickel particles causes a darkened appearance in the film exactly where the magnetic field is impinging on the film. As a result, an exact two-dimensional image or impression of the magnetic pole or pole pattern (if there are more than one) is produced. This image is easily erased once the film is removed from the magnetic source and the nickel particles are allowed to freely re-disperse within their gelatinous cells. A common bar magnet can be swiped across the film to ensure complete erasure of the previous image, or by reapplying the film to another magnetic source the new image produced will completely replace the old one.

Because of the small size of the colloidal Nickel particles, the film can detect fields as low as only a few gauss and still produce a clear image.

Due to the film's high flexibility, it easily conforms to magnetic surfaces with high degrees of concavity and convexity. Also, because the film is so thin and can be cut down to practically any size without losing its properties, it can be used in tighter places inaccessible to the bulkier, unalterable devices. Finally, since there are no moving or electronic parts, the film never needs maintenance or repair.
Made in USA DC MAGNETIC FIELD VIEWER GEL (Cat. #A1121) .......... $59.00 add to cart


Filing Viewer Remember playing with iron filings and a magnet? The magnet makes the filings stand up on end and arrange themselves in beautiful patterns according to the magnetic field lines. The problem was that the filings would stick to the magnet so hard it was difficult to remove them AND filings that spilled made a huge (and rusty) mess. This clever device solves both problems by enclosing the iron filings in a clear hard plastic case! Now students, children and adults too can enjoy learning about magnetic attraction the fun and clean way. You must supply your own magnet, but just about any magnet will do. And when you are done, just put it away in a drawer and there's nothing to clean up. 3" round.

Made in USA Filing Viewer (Cat. #A1122) …......................…. $4.95 add to cart


Hall Effect Semi-Conductor Sensor Sensitive to Magnet Polarity

This component can be used in a circuit to open and close a contact when exposed to alternating N and S poles of a magnet. Will also work if exposed to the same pole on alternative sides of the sensor.

    Many uses including:
  • Counting revolutions, oscillations, or sequences
  • Turning LEDs, alarms, or other devices on/off
  • Detecting presence of magnetized materials
  • Intruder/theft alarms
  • Monitor start/stop of a moving process
  • Robotic effects and magic tricks!
Linear Hall Effect Sensor Schematic Schematic of an example circuit included. Part number may vary from picture. Very unique!

Hall Effect Semi-Conductor Sensor (Cat. #A402) ........... $2.00 each add to cart


1.75 Inch Compass Looking for the cheapest way to determine if something is magnetized? Want a simple device for comparing magnets? Doing a school project? Lost? For hundreds of years, mankind has used the trusty compass to guide him through the Earth’s magnetic field. Measure the deflection of the needle from magnetic North at known distances using this nice 1.75 inch diameter compass to quantify and compare DC magnetic fields, track down magnetized components, or evaluate magnetic shielding performance. Extra large, easy to hold, and very easy to see. High resolution with large needle. Aluminum case with loop for key ring or lanyard. Check DC magnetic fields, identify magnetized steel, or just find your way home! Much cleaner than iron filings. Makes a great science fair project too. Compass must be held horizontally to operate. May look different from picture.

1.75 inch Compass (Cat. #A123) …............. $2.50 add to cart


MagnaProbe The perfect way to visualize the three dimensional nature of a DC magnetic field. MagnaProbe is a small magnet suspended in a gimbal mounting. The magnet's North pole is colored red, South is blue, to easily indicate polarity of the field under investigation.

The MagnaProbe can be used to show :

  • forces between magnetic poles
  • induced magnetism
  • the shapes of magnetic fields between like and unlike poles
  • mapping and direction of a magnetic field around a bar magnet, a wire or a coil
  • properties of a field produced by an electric current
  • shape, intensity, and distribution of field lines after magnetic shielding

This is a very important tool for mapping the direction of field lines prior to shielding design (speaker shielding for example), and is a great teaching tool.

MagnaProbe (Cat. #A420) …………..… $14.95 add to cart


Industrial Magnetic Strength Meter

Pocket Magnetometer DC magnetic fields can develop in many steel or iron objects if they have been exposed to magnetic fields, current, or friction. Even structural members in homes and barns have become magnetized due to stray voltage. Pocket Magnetometer This hand-held device detects residual magnetism in steel parts quickly and accurately. Simply place the test edge near or against the object being tested, and the needle gauge points to a reading representing the magnetism in the object at that site as well as polarity. Will also verify thoroughness of de-magnetizing. Check out your car, bed frame, desk furniture or any other metal objects you spend time with. Can also be used to check the strength of magnets. Two models in stock: -20 to +20 and -100 to +100 Gauss.

(20-0-20G) MAGNETOMETER (Cat. #A142-20) .............. $53.95 add to cart

Made in USA (100-0-100G) MAGNETOMETER (Cat. #A142-100) ...... $145.00 add to cart

Other ranges available as a special order. Contact us for details.

What our customers tell us:

"Your 20-0-20 gaussmeter is nothing short of magnificent. So handy and nicely pocket sized and sensitive (at first I thought the zero set was off until I reallized it was registering the Earth's magnetic field -verified by rotating the instrument in the field.) Your catalog description is much too modest."

D.S., Janesville WI

“I use this meter frequently to test for good magnetism of guitar pick-ups. It does what I need! ”

R.S., Manchester NH


Two High Sensitivity Meters in One AC/DC milliGaussmeter

A useful and reasonably priced meter for measuring both AC and DC magnetic fields. Easy to use with external single axis axial 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 ΅T (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
  • 39 inch long (1 meter) cable on probe
  • 3.5 mm data ouput jack

Uses 6 AAA batteries (not included). Can also be power by external DC 9V adapter (sold separately).

AC/DC milliGaussmeter (Cat. #A112) ….. $399.95 add to cart

Hall Effect Gaussmeter


Intermediate Range

Versatile enough to classify magnets, measure residual magnetism, and check fields from DC circuits. Also has sensitivity to low frequency AC magnetic fields.

High linearity and high accuracy (3%) with residual sensitivity up to 10 Hz. 4 ranges: 2, 20, 200, 2000 Gauss. 3½ digit display, yields 1 mG resolution (on lowest scale). Rugged detachable probe on 3.5 ft inch cable.

200 mV DC recorder output permits data logging/recording.

Includes a 9V battery plus AC adapter, reference magnet, and padded hard case. Made in USA. Two year mfr warranty. Choose transverse, ultra-thin (.020 inch) transverse, axial probe, or combination. Sensor size is .04 x .08 inch.

Ultra Thin Probe A T Probe orientation Hall-Effect Gaussmeter with transverse probe
- (Cat. #A1101-T) ....................... $525.00
add to cart

Hall-Effect Gaussmeter with ultra-thin (0.55 mm) transverse probe
- (Cat. #A1101-UT) .................... $525.00
add to cart

Hall-Effect Gaussmeter with axial probe
- (Cat. #A1101-A) ...................... $525.00
add to cart

Hall-Effect Gaussmeter with axial & transverse probes
- (Cat. #A1101-AT) .................... $650.00
add to cart

Connector Cable
Perfect for connecting the output on this meter to a DMM with PC Interface for data logging and graphics. 3.5 mm mono audio plug on one end, dual banana plug on other end.
3.5mm Audio Plug to Dual Banana Connector Cable (Cat. #3.5-Ban) ........ $14.95 add to cart


Kilo Gaussmeter For Strong Field Applications

This is a high quality, reasonably priced digital meter & it is invaluable for reliable measurement of permanent magnets, magnetized rocks and metals, the Earth's magnetic field, and any DC magnetic field. Offering 3½ digit bipolar display, 9V battery powered and comes with an AC power adapter for extended benchtop use. KiloGaussmeter Frequency Response Probe (High Linearity Hall Generator) with 3.5 ft cable is included providing nearly linear response from DC to 10 Hz. Useful 4 ranges covering 0 - 20, 200, 2000, 20,000 Gauss with a 3% accuracy guarantee. Two year parts and labor warrantee. 200mV DC recorder output (which can be used with DMM (Cat. #A192) to interface this unit with your PC) is included. Choose transverse, ultra-thin (.020 inch) transverse, axial probe, or combination.

Ultra Thin Probe A T Probe orientation KiloGaussmeter with transverse probe
- (Cat. #A2100-T) ...................... $525.00
add to cart

KiloGaussmeter with ultra-thin (0.55mm) transverse probe
- (Cat. #A2100-UT) ................... $525.00
add to cart

KiloGaussmeter with axial probe
- (Cat. #A2100-A) ...................... $525.00
add to cart

KiloGaussmeter with axial & transverse probes
- (Cat. #A2100-AT) .................... $650.00
add to cart

Connector Cable
Perfect for connecting the output on this meter to a DMM with PC Interface for data logging and graphics. 3.5 mm mono audio plug on one end, dual banana plug on other end.
3.5mm Audio Plug to Dual Banana Connector Cable (Cat. #3.5-Ban) ........ $14.95 add to cart


Geomagnetometer Our Most Sensitive DC Gaussmeter

You simply won't find anything this sensitive in this price range! Want to measure the Earth's magnetic field with great precision? Want to detect magnets from a distance? Breaks in magnetized steel cables? Need to comply with shipping regulations? Then this is the unit for you. Similar in appearance to the DC Gaussmeter listed above, but 10,000 times more sensitive. Only 3" x 4" x 7" and operating on common 9V batteries for total portability and convenience plus AC power adapter included for extended benchtop use. Geomagnetometer

An axial probe (High Sensitivity Hall Generator) with coiled cable is included providing nearly flat response from DC to 10+ Hz. Large 3½ digit bipolar display. 4 ranges: 0-2, 20, 200, 2000 mG (yes milliGauss!) and a 5% error guarantee. Two year parts and labor warrantee. 200mV AC recorder output included to interface this unit with your PC, scope, analyzer or recorder. Allows analysis of ultra-low frequency signal waveform, frequency and spectrum. Click here for more information.

Geomagnetometer (Cat. #A3100) ............ $750.00 add to cart

Connector Cable
Perfect for connecting the output on this meter to a DMM with PC Interface for data logging and graphics. 3.5mm mono audio plug on one end, dual banana plug on other end.
3.5mm Audio Plug to Dual Banana Connector Cable (Cat. #3.5-Ban) ........ $14.95 add to cart

Zero Gauss Chamber Zero Gauss Chamber (Cat. #A3105) ......... $350.00 add to cart

DC/AC Gaussmeter

Magnetic Field Strength with Frequency, DC -1 kHz DC/AC Gaussmeter

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, datalogging up to 32,000 data points, and 3 % error guarantee. External probe.

Operate in 1 of 3 modes:
3 Ranges:
DC only300 G (100 mG resolution)
AC only: 20 Hz - 1 kHz3 kG (1 G resolution)
AC + DC: 0 – 1 kHz30 kG (10 G resolution)

Completely portable. 4 AA alkaline batteries included and optional 6V DC adaptor available. Choose transverse, ultra-thin (.020 inch) transverse, axial probe, or combination. Zero gauss chamber (included) helps when zero-ing the unit.

DC/AC Gaussmeter Axial Probe (Cat. #A1132-A).................................. $1195.00 add to cart
DC/AC Gaussmeter Trans Probe (Cat. #A1132-T)................................. $1195.00 add to cart
DC/AC Gaussmeter Ultra-thin (0.55mm) Trans Probe (Cat. #A1132-UT)............ $1195.00 add to cart
DC/AC Gaussmeter Both A&T Probes (Cat. #A1132-AT)..................... $1445.00 add to cart

Zero Gauss Chamber

Zero Gauss Chamber

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) ......... $350.00 add to cart

DC/AC milliGaussmeter

Ultra-Sensitive Magnetic Field Strength with Frequency, DC -750 Hz DC/AC milliGaussmeter

Similar to the AC/DC Gaussmeter above, but much more sensitive...

  • 3 modes of operation: DC, AC:(5 Hz - 750 Hz) and AC + DC:(0 – 750 Hz)
  • 1 uG to 4000 mG
  • Resolution @ Scales:
    • 4 mG: 1 uG,
    • 40 mG: 10 uG,
    • 400 mG: 0.1 mG,
    • 4000 mG: 1 mG
  • True RMS measurement with Max. & Min. peak hold
  • Frequency indicator
  • 3% error guarantee
  • Auto or manual ranging with auditory alarm
  • Datalogs up to 32,000 data points
  • PC interface w/ RS-232 communication port
  • One volt full scale Analog Output
  • Two years parts & labor warranty
  • Weight: 1 lb (453.6 grams)
  • Axial Probe included
    4 AA Alkaline Batteries, 6V DC adaptor and Zero Gauss Chamber included

    DC/AC milliGaussmeter (Cat. #A3200).................................. $1695.00 add to cart

    Deluxe Instrument Case


    Perfect for instruments or cameras. Fits plenty of stuff in a compact space. This rugged case features aluminum trim, triple riveted corners, carry handle and locking metal clamp hinges. Black hard sidewalls. Padded inside walls but no foam. 12'' x 10'' x 4''.
    Deluxe Instrument Case (Cat. #A711) …… $18.95
    add to cart

    Link to AC GaussmetersDC Gaussmeters on this page

    Can't decide which meter is right for you?
    Click here to go to the handy Meter Selection Guide.

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