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Whether teaching electricity, magnetism, or electronics in the classroom, or a science fair project or self-teaching, you will find the right equipment for the task.

What do you want to do?

Detect or characterize DC magnetic fields: DC Magetic Field Devices
Detect or quantify AC magnetic fields: AC Magetic Field Devices
Shield Magnets: Magnetic Shielding Alloys
Measure frequency, current or voltage: DMM, O-scopes, and Frequency Counters
Create frequencies: Signal Generators
Teach/Learn circuit soldering and asembly: Assembly Kits
Make unique wearable electronics: Conducitve fabrics, threads and switches
Ideas for lessons, experiments: Experiment Books



  DC Magetic Field Devices


MAGNETIC FIELD VIEWER CARD

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. Flexible thin rubber magnets show up as stripes. 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"

DC MAGNETIC FIELD VIEWER CARD (Cat. #K1120) .......... $2.75 add to cart
Case Price [50 units] (Cat. #K1120-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.
DC MAGNETIC FIELD VIEWER GEL (Cat. #K1121) .......... $59.00 add to cart



FILING VIEWER

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.

Filing Viewer (Cat. #K1122) …......................…. $4.95 add to cart



1.75 INCH COMPASS

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. #K123) …............. $2.50 add to cart



MAGNAPROBE

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. #K420) …………..… $14.95 add to cart



"POCKET" MAGNETOMETER

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 (weak) magnets. Two models in stock: -20 to +20 and -100 to +100 Gauss.

(20-0-20G) MAGNETOMETER (Cat. #K142-20) .............. $53.95 add to cart
(100-0-100G) MAGNETOMETER (Cat. #K142-100) ...... $145.00 add to cart

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




AC/DC milliGAUSSMETER

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 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 ouput jack

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

AC/DC milliGaussmeter (Cat. #K112) ….. $399.95 add to cart



KILOGAUSSMETER

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, and any DC magnetic field. Offering 3˝ 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. #K2100-T) ...................... $525.00
add to cart

KiloGaussmeter with ultra-thin transverse probe
- (Cat. #K2100-UT) ................... $525.00
add to cart

KiloGaussmeter with axial probe
- (Cat. #K2100-A) ...................... $525.00
add to cart

KiloGaussmeter with axial & transverse probes
- (Cat. #K2100-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

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 3˝ 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. #K3100) ............ $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. #K3105) ......... $350.00 add to cart

Click for even more DC Gaussmeters



  AC Magetic Field Devices


Magnetic Pickup

MAGNETIC PICKUP

Build Your Own Gaussmeter

This AC magnetic field probe generates an AC voltage when exposed to AC magnetic fields. Although we do not specify how the output from this unit varies with frequency, we do know that the greater the magnetic field, the higher the voltage generated (at 60 Hz, it produces about 1 mV per 20 mG). It can be connected to a DMM, analog voltmeter, oscilloscope, audio amplifier, or recording device. Connect 3 of them in series and create a 3-axis unit. It can also be used in reverse: apply a small current to produce a magnetic field (careful, don't overdo it). It is quite small: only 0.7" long x 0.7" diameter, with a removable rubber suction cup attached. Has 36" lead and 1/8" (3.5 mm) mono plug.

Magnetic Pickup (Cat. #K175) …........…. $4.95 add to cart



BUDGET BUZZ STICK

Listen to Magnetic Fields

Budget Buzz Stick 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 3 foot cable and audio amplifier with adjustable volume. 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.

Budget Buzz Stick (Cat. #K175-B) ...............… $16.94 add to cart



Gauss Master

GAUSS MASTER™

Popular 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.

AxisRangeResolutionFrequencyAccuracy
10-1 mG
0-10 mG
0.1 mG
1 mG
50/60+ Hzno spec
What is unique about this meter? Lightning fast needle response, audio function
ALKALINE 9V BATTERY

Includes nice instructions on how to perform
a proper survey of your home, office, or school yard.

Gauss Master (Cat. #A130) .................................. $34.95 add to cart

Case Price [48 units] (Cat. #A130-case) ............ $960.00 add to cart

Quick Start Instructions for GaussMaster (pdf)


Digital Gaussmeter


SINGLE AXIS DIGITAL AC GAUSSMETER / TESLAMETER

Rugged, Compact, & Lightweight Magnetic Field Meter

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.

ALKALINE 9V BATTERY 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.

AxisRangeResolutionFrequencyAccuracy
10-199.9 mG
0-19.99 microT
0.1
0.01
30 - 300 Hz4% ±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. #K111) ..... $79.95 add to cart

Click for even more AC Gaussmeters



  Conducitve fabrics, threads and switches


QTC™: Quantum Tunneling Composite

QTC™: Quantum Tunneling Composite

Transforms from Insulator to Conductor with Pressure

This flexible polymer exhibits extraordinary electrical resistance change when deformed by squeezing, pulling or twisting. In practice, QTC™ can be connected in quite simple ways to create anything from switches to force sensors. In its normal, uncompressed state, QTC acts as a near perfect insulator, but as it is gradually compressed it will allow more current through until it is nearly a perfect conductor. Fun to experiment with and great for turning anything with a screw-in battery compartment into an effective dimmer switch! Can also be used between layers of conductive fabric to make variable switches and variable resistors or capacitors.

It is claimed that electrons ‘pass’ through the insulation by a process called quantum tunneling. In classical physics, the electrons cannot pass through an insulating barrier, but according to quantum theory a wave can – and this is what happens in QTC™. Another way of describing the quantum tunneling effect is to say that a non-zero probability exists of electrons one side of the insulation barrier appearing on the other side.

QTC™ can be used as a solid state switch - in the "off" state it is a good insulator and in the "on" state it is as good as a metal conductor. It can be used to detect even very small changes due to compression, tension or other stresses and it can carry significant currents allowing for the direct control of loads. QTC™: Quantum Tunneling Composite QTC™: Quantum Tunneling Composite

Rated for over one million compressions.
The maximum specified voltage is 40V, maximum current is 10 Amps.
Temperature variation (for a current of 1microA) shows an approximately linear increase in the resistance (R=63MOhm to R=1240MOhm) observed from 25°C to 180°C.
Each piece is 4x4x1 mm.

QTC™ (Cat. #K253) ............ $2.00 add to cart



TEXTILE PUSH BUTTON KIT

Dead-man Style Fabric Switch

Textile Push Button Kit Here is a very unique switch. Knitted from polyester and stainless steel fibers, an electrical contact is made when the 4x4 cm patch is compressed. Use it for robotic applications, occupancy sensors (in a seat for example), or intrusion alarms (when stepped on). Also great for artistic purposes: put it in a shoe, or attach it to a garment (glove tip or elbow patch for example) to control lights or sounds when you move. Kit includes 2x3 inch fabric switch, LED bulb, conductive thread, instructions, one CR 2032 3V coin battery with battery holder. Just add your own sewing needle, to make the simple educational project shown.

Instructions:
Textile Push Button Kit (.pdf)

Textile Push Button Kit (Cat. #K301) ....... $16.00 add to cart



PRESSURE SENSITIVE FABRIC SWITCH

Tape format, 4 cm x 100 cm

Pressure Sensitive Fabric Knitted pressure sensitive fabric made of three layers. Two layers of stainless steel are separated by one layer of acrylic fabric. When pressed, the two external layers touch, allowing current flow. This basic sensitive fabric has a functioning equivalent to a push button switch. When you press it you close an electrical circuit. This fabric is compatible with the Arduino platform, and it can be connected to an Arduino controller without any additional hardware.

Instructions:
Connecting To A Pressure Sensitive Fabric Switch (.pdf)
How to connect Arduino to the Pressure Sensitive Fabric Switch (.pdf)

Pressure Sensitive Fabric Switch (Cat. #K302) ....... $25.00 add to cart



SOFT FABRIC POTENTIOMETER KIT

Flexible, Variable Resistance

Pressure Sensitive Fabric As simple as playing with your zipper. This soft 39 inch fabric potentiometer is perfect for controlling the brightness of an LED or the changing the tone of a buzzer to make cool sound effects. Can also be used as a position sensor. Resistance of this component is changed by sliding the position of the ring.

Compatible with Arduino inputs. Very easy to connect. Kit includes 1 meter of knitted conductive tape, instructions for a simple circuit using a Lilypad Arduino (not included), and a metal ring.

Instructions:
Connecting the Soft Fabric Potentiometer Kit to a Lilypad Arduino (.pdf)

Soft Potentiometer Kit (Cat. #K303) .......... $7.00 add to cart



BOBBIN THREAD

Conductive Silver Plated Nylon

Need to sew with conductive thread? Want to add a conductive stitch to a non-conductive fabric? Only need a little bit?

With this conductive thread, you can add conductivity to any fabric, make conductive traces as easily as sewing, even use it as un-insulated low voltage wiring. Great for embroidery too.

You get 2 bobbins: one large and one small, to fit most sewing machines. Can also be hand sewn. Approximately 20 meters of thread per bobbin. Hand wash, no bleach. Hang dry. Do not dry clean. Needle and thimble not included. Pressure Sensitive Fabric

  • Nylon 6.6 filament yarn plus 99% pure Silver
  • Yarn count: dtex 140f17 x2 ply (about 280/1 dtex)
  • Twist of single yarn: 620 tpm S
  • Turns of twist: 550 tpm Z
  • Yarn count of twist: Nm 35
  • Tenacity: about 70±5 cN/dtex
  • Elongation: about 40±5%
  • Resistivity: <30 Ohm/cm
  • RoHS compliant

Bobbin Thread (Cat. #K304) .......... $13.00 add to cart

Click for Conductive Fabrics and Textiles



  DMM, O-scopes, and Frequency Counters


COMPACT DIGITAL MULTIMETER

Bargain Priced, Full Featured

Very simple and economical DMM with the all important ability to read down to 1 mV AC. Perfect for Body Voltage measurements or use with a variety of EMF probes. Autoranging, ergonomically designed to easily fit in the palm of your hand. 3ľ digit, 3999 count display measures AC/DC voltage and current, ohms, diode check and transistor HFE. COMPACT DIGITAL MULTIMETER

    More features
  • 1/2" high LCD digits
  • Continuity buzzer
  • Includes test leads, 2 AAA batteries and owners manual
  • Dimensions: 5 3/8" (H) x 3" (W) x 1 3/8" (D)
    Ranges
  • DC Voltage: 400mV, 4V, 40V, 400V, 500V ±(0.8%+1)
  • AC Voltage: 4V, 40V, 400V, 500V ±(1.2% +3)
  • DC Current: 400µA, 4000µA, 40mA, 400mA, 4A, 10A ±(1%+2)
  • AC Current: 400µA, 4000µA, 40mA, 400mA, 4A, 10A ±(1.5%+5)
  • Resistance: 400O, 4KO, 40KO, 400KO, 4MO, 40MO ±(1%+2)

Compact DMM (Cat.#K411) .................. $29.95 add to cart



AC/DC CLAMP METER

AC/DC CLAMP METER

Best Way To Locate Net Current

Place the jaws of this clamp meter around wires, pipes, conduit, hoses, or any other object (up to 42mm diameter) to determine if magnetic field producing electric current is flowing. It’s the easiest way to check your water main, radiator pipes, and wires without disconnecting them. Net current and many wiring errors can be detected when the current in the hot lead does not equal the current in the neutral… or worse, if there is current running on the ground wire. This is a “must have” tool for EMF consultants and other EMF detectives.

    This unit also has many other very useful features:
  • True RMS for AC voltage and current
  • Auto/manual range
  • Data hold
  • MAX / MIN function
  • AC/DC voltage, AC/DC current, resistance, frequency
  • Continuity test
  • Diode test
AC/DC CLAMP METER
    More specifications:
  • Conforms to the IEC1010-1 & IEC1010-2-032 standard
  • Display : 3999 counts and 42 segment bar graph
  • True RMS for AC voltage and current
  • Auto zero key for DCA
  • Back light and Jaw light
  • Auto power off
  • DC Voltage: 4 / 40 / 400V ±0.8%, 1000V ±1.0%
  • AC Voltage: 4 / 40 / 400V ±1.0%, 700V ± 1.2%
  • DC Current: 400 / 1000A ±3.0%
  • AC Current: 400 / 1000A (<600A ±2.5%, 600A ±3.0%)
  • Resistance: 400 / 4k / 40K / 400k / 4M ±1.0%, 40M ±2.0%
  • Frequency: 40Hz ~ 100KHz ±0.1%
  • Frequency range from current clamp: 40Hz ~ 400Hz ±0.1%
  • Size: 225 x 86 x 33mm; Weight: Approx.320g
  • Requires 3 AAA batteries
See Tracing Magnetic Fields DVD (Cat. #K531) for a fabulous demonstration of how to use a clamp meter.

AC/DC Clamp Meter (Cat. #K416) ...... $89.95 add to cart



LOW FREQUENCY COUNTER

Low Frequency Counter Hand-Held Counter With Bench Top Performance

So you want to check extremely low frequencies down to 3 Hz? Doing bio-magnetic or paranormal work? Interested in harmonics in your power? The Low Frequency Counter provides outstanding value and versatility that rivals or exceeds counters costing much more. Large eight digit LCD display gives plenty of information about the predominant incoming frequency and the good nominal input sensitivity provides stable readings. Covers the entire frequency range of 3 Hz to 3 GHz so you can check most low frequency sources. Probe/antenna not included, but it works well with telescoping antenna (see below), and other probes available from The EMF Safety SuperStore with suitable adapters.

Click here for More Information about this product

Low Frequency Counter (Cat. #K422) …………...…. $299.95 add to cart

Telescoping Antenna with BNC Connection (Cat. #K128-T) ...... $15.00 add to cart



  Signal Generators


SCHUMANN SIGNAL GENERATOR

SIGNAL GENERATOR

Tunable, Adjustable, Powerful

With this device you can precisely select any frequency from .01 Hz to 2 MHz, and adjust the power output as well. Produces a mammoth intensity signal: from 1 mG to over 100 mG! Digital display leaves no uncertainty about what frequency is selected. Includes memory for up to 10 favorite frequencies. USB powered from your computer or AC adapter (provided).

This unit can also be used as an Audible Tone Generator or Frequency Counter. Produces Sine, Sawtooth and Square wave patterns. Step by step instructions included.

Schumann Signal Generator (Cat. #K388) ............... $149.95 add to cart


BNC Breakout Gator

BNC Breakout Cable

36 inch long, BNC male one end, booted alligator clips on other end. Permits easy connection from most devices to input or output of signal generator.

BNC Breakout Gator (Cat. #K462-G) .............. $5.95 add to cart



BNC Cable

BNC Cable

36 inch long coaxial, BNC male connector on each end.

BNC Cable (Cat. #K128-BNC) …. $4.95 add to cart



Frequency Generator

FREQUENCY GENERATOR

"Low Frequency Test Signal Generator"

Make some waves! Need a source of 20 Hz to 150 kHz frequencies? Handy little unit fits in your shirt pocket and is very simple to operate. Produces nice clean sine waves (adjustable intensity up to 1.2V rms) or square waves (p to 8V p-p) with 5% frequency accuracy. Simply dial in the desired frequency. Uses 9V battery (50 hrs typical use). Includes low battery indicator, test leads and 9V battery.

Check the response of your gaussmeter to various frequencies (connect the Frequency Generator to the Degaussing Coil to generate several mG fields at various frequencies), test your frequency counter, connect to a speaker/headphones to test your hearing range! Also great for field/bench service of audio equipment, car stereo, etc. Bargain price!

Generator frequency20Hz~150KHz in 46 steps ±0.5dB
Sine wave output1.2V RMS minimum in 600 Ohm
Distortionless than 0.05% (200Hz~15KHz)
0.1% (50Hz~30KHz)
less than 0.3% (20Hz~100KHz)
Square wave output8V p-p max. (no load)
Rise/fall timeless than 0.5µsec
Overshootless than 2%
Duty ratio50% ±5%
Output impedence1 KOhm
Dimensions3 3/8" (W) x 6" (H) x 1" (D)

Frequency Generator (Cat. #K423)……. $74.95 add to cart


DEGAUSSING COIL

Large Induction Coil

This 6 inch coil can be connected to a voltage source to produce a magnetic field. Do experiments where current and frequency are varied. Use a gaussmeter or clamp meter to measure the effect.

Or use 2 coils to study the induction effect. Inject a signal (up to 115V) into one coil and measure the signal output from the other one. Look at the effect of current, frequency, orientation and distance.

In addition, the coil can be used as a magnetic field probe. Measure the voltage output when the coil is exposed to various AC magnetic fields. Notice the effect of frequency, orientation, and field strength.

But wait, there's more: Coil Removes Magnetic Fields from Steel and Iron

Degaussing Coil Want to remove the magnetic fields from your small steel objects? Want to degauss your TV, computer monitor or erase magnetic media like credit card strips, diskettes and audio tapes? This degaussing coil can do all that and more!

To demagnetize something ferroelectromagnetic you expose it to a strong AC magnetic field that slowly decreases. The idea is to magnetize the object completely in one direction, then slightly less in the opposite direction, then repeat with ever smaller decrements until only a very small residual magnetic field remains. Simply plug in this degaussing coil and hold it near the object you wish to treat. Then slowly back away until your are about 3 –4 feet away from the object. It's that simple!

Be careful when you handle this demagnetizer, don't leave it on more than absolutely necessary, and do not expose yourself unnecessarily. The magnetic field emitted can be well into the 17 Gauss range.

Re-check regularly, about every six months to a year, as degaussing may need to be repeated. A full 6" in diameter coil with on/off switch (style may differ slightly from picture). 115VAC, UL approved. Made in USA.

Degaussing Coil (Cat. #K730) ….................. $29.95 add to cart



  Magnetic Shielding Alloys


MagnetShield

High Saturation Magnetic Alloy

Magnet Shield

First line of defense for shielding strong magnetic fields from magnets, speakers, small transformers and motors. Strong magnetic fields are harder to shield because they tend to "saturate" the shielding material. This 4" wide foil is a hefty .010" thick and has an exceptionally high magnetic saturation of 21400 Gauss and maximum permeability of 4000. Tin plated for excellent corrosion resistance and better conductivity, it can be soldered or painted.

MagnetShield typically reduces fields up to a factor of 2 or 3 depending on size/shape of the shield. Can be used in multiple layers, and/or in combination with a higher permeability alloy such as Joint-Shield for higher attenuation. Annealing is not necessary with this material. Compare the magnetic shielding of various houshold items: Aluminum pie plates, steel cookware, Silver spoon etc.

For increased shielding effectiveness, consider the following strategies:

  • Good: Layer(s) MagnetShield
  • Better: One or more layers of MagnetShield (closest to the source of field), followed by one or more layers of a high permeability material such as Joint-Shield or MagStop Plate.

Applications Notes:

- The magnets will be attracted to the shield (this is true of ALL magnetic shielding alloys). If you want to shield 2 adjacent magnets from eachother, each magnet should have its own shield.
- The size, shape, and position of the shield all matter in terms of shield performance. For example, larger shields are better than small shields. Closer to the magnet is better than farther from the magnet. And parallel to the magnetic field lines is better than perpendicular to them.
- You will likely need more than one layer of shielding material, depending on the strength of your magnets. More layers = more attenuation.

How do I stop the attraction/repulsion between 2 magnets?

Click here for Specs on Magnet Shield

4 inch wide Ribbon:
MagnetShield (Cat. #K274) ........................... $4.50/lin ft add to cart



GIRON

GIRON

Breakthrough In Magnetic Shielding Flexibility

GIRON Magnetic Shielding Film, which does not contain Nickel, is unlike any other magnetic shielding material available on the market today. Suitable for high field strength applications requiring high saturation and good permeability, it is both thin and strong, and unlike Mu-metal™ it is very tolerant to bending or shaping without losing its shielding properties.

GIRON GIRON is a woven, laminated material. Cuts neatly with snips or sheet metal tools, and can be used either flat or molded into shapes for best performance.

Suitable for small shields on magnets, motors, speakers and appliances such as refrigerators, vacuum cleaners etc. Also great for lining car floor or firewall. Perfect for full or partial wall / floor shielding in rooms too! Can be glued, taped, nailed, screwed or riveted into place. Could even be used to make a (heavy weight) vest to shield a person's torso! Works with AC or DC magnetic fields (0-1000 Hz), and will tolerate temperatures from 32° to 122°F. Coating is UV sensitive, cover if installation is exposed to direct sunlight.

  • Initial permeability: 500
  • Relative permeability: 7000
  • Saturation induction: 2,0 T
  • Curie Temp.: 740°C (1364°F)
  • Weight is approx 1 lb per square foot

25.5 inch wide, 1 mm thick. Weighs 3.5 Kg/m˛ (about 15 pounds per 10 foot length). Edges are sharp!

GIRON (Cat. #K273) ............... $44.95 per linear foot add to cart

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  Assembly Kits


TRI-FIELD METER KIT

TRI-FIELD METER KIT

Build Your Own Multi-Purpose Meter

Three separate field sensors to provide a really cool readout on two Sci-Fi styled LED bar graphs! Utilizing the latest technology, including Hall Effect sensors, you can walk around your house and actually "SEE" these fields around you! Can detect the magnetic field of the earth...THAT'S sensitive! Also detect radiation from monitors, TV's, electrical discharge, and RF emissions. You will have fun finding these fields and at the same time learn the technology behind them.

Three position selector switch that lets you select which type of field you want to detect: either RF, DC magnetic, or electric. Display consists of two LED bargraphs, one at the top and one at the bottom. These indicate the relative strength of the field you are detecting. All in all, it’s a great way to learn about the use of electronic components as sensors and own a little piece of sci-fi at the same time. A great teaching tool for kids of all ages; show them the invisible fields all around them and learn about electronic circuitry and soldering.
  • Detect RF from your radio transmitter, computer monitor, or cell phone.
  • Pick up the field from magnets around your house, even the earth!
  • “See” the charge on a staticly charged hairbrush or comb.
  • Learn how to use electronic parts as sensors.
  • Sense different magnetic poles!
  • Runs on 4 AAA batteries, not included.
  • Small, handy size for portability.
  • Fun LED displays.
  • Single Axis
Note: this is not the same meter as the “Trifield Meter”.
Requires adult supervised assembly, soldering, and some knowledge about electronic components.

Tri-Field Meter Kit (Cat. #K113) ....................... $74.95 add to cart

YouTube demonstration of this product:



Deluxe Instrument Case

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. #K711) …… $18.95
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  Great Books for Experiment Ideas


Safe & Simple Electrical Experiments

Safe & Simple Electrical Experiments by Rudolf F. Graf

Here are 101 entertaining experiments for fast and reliable learning of the basic principles of electricity. Categorized into static electricity (38 experiments), magnetism (32), and current electricity and electromagnetism (31) for maximum exposure to the fundamentals. Each experiment beginning with a list of safe and inexpensive materials needed and some introductory remarks, is presented with detailed step-by-step instructions and clear illustrations. The reader learns where to get/make electricity, how to store it, and how to use it in a number of creative ways. Although carefully selected to be safe for children, this book is suitable for young and old students of electromagnetism. 117 paperbound pages. 1964

Safe & Simple Electrical Experiments (Cat. #K593) ..................... $7.95 add to cart



Mondo Magnets

MONDO MAGNETS

40 Attractive (and Repulsive) Devices and Demonstrations
by Fred Jeffers

Surprising and seemingly impossible effects result from the 40 experiments included in this fascinating science resource—all with a concise explanation of the underlying magnetic physics. Each experiment—such as using a common refrigerator magnet to create a three-dimensional image or floating a magnet and carbon sheet in midair—is outlined with step-by-step instructions and diagrams that illustrate the key concepts of magnetism. Even the most experienced science teacher or at-home tinkerer will find dozens of new tricks in this amazing collection. Great for students. Clearly written and easy to understand with lots of good photos. 2007

Mondo Magnets (Cat. #K601) ..… $16.95 add to cart



"Spectacular Science Projects:"
Mind-Boggling Experiments You Can Turn Into Science Fair Projects
by Janice VanCleave

ELECTRICITY

Electricity Includes 20 simple and fun experiments that allow you to learn about electric charges with a simple experiment using modeling clay and a plastic straw; about voltage using a bowl, paper towels, and a raw egg; about conductors with some clothespins, aluminum foil, and a flashlight bulb; plus dozens of additional suggestions for developing your own science fair projects. All experiments are safe, use inexpensive household materials, and involve a minimum of preparation and clean up. Clearly written. 1994.

Electricity (Cat. #K626) ..................... $14.95 add to cart


MAGNETS

Magnets

  • How does a compass work?
  • What is a magnetic field?
  • How can you make electricity with a magnet?
Janice VanCleave's other book includes 20 great experiments that allow you to answer these questions, plus many more ideas for developing further science fair projects. Learn about magnetic poles; about magnetic force fields; even magnetic shielding! Author is a former science teacher and science lecturer. 1993.

Magnets (Cat. #K627) ..................... $12.95 add to cart


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