Where to obtain the supplies and equipment
Catalog houses and stores
Please note: the information at the end of several articles refers to the part number of that item at the source indicated. Arbor is Arbor Scientific, ScientificsOnline is ScientificsOnline , AS&S is American Science and Surplus, EdIn is Educational Innovations.
Wondered where to purchase the magnets, motors, and other things you need to make the demonstrations discussed on these web pages? Try these places:
NIB magnets, experimental kits, etc:
first4magnets.com
for a huge variety of NIB, ceramic, alnico, wind
generator, high-temp magnets,
assemblies, ferrofluid, gauss meter, and more - located in the UK
Arbor
Scientific Arbor has very handy instruction sheets and
ideas which they ship with their kits
K&J
Magnetics for a large variety of NIB magnets
Teachersource
Educational Innovations, have magnets, games, toys, big
selection
Steve
Spangler Science great experiments, videos, supplies
for the classroom and home
Apex
Magnets with several items to choose from
Magcraft for MAGCRAFT® NIB
magnets, ferrofluid, pyrolytic graphite disks, gaussmeters, viewing film, etc.
ScientificsOnline
lots of science supplies,
magnets, science fair items, stuff
BuyMagnets.com
for a large variety of NIB, ceramic, alnico magnets,
assemblies, industrial separators, electromagnets
SargentWelch
lots of science supplies
ScienceKit
lots of science supplies
Ward's
Natural Science lots of science supplies
Dowling
Magnets for a train
maglev kit and strip magnets
AUSSIE
magnets (the Magnet Shop) for
those in Australia who need a great source for magnets!
Lodestone
Industries also
in Australia, with good support information
Shaw
Magnets in the UK
The
Magnet Source
Amazing
Magnets for NIB magnets, steel
balls, magnetic sculptures,
ferrofluid, great site!
Applied
Magnets for NIB magnets, SmCo magnets, spools of
magnet wire, parts for wind generators, etc
SuperMagnete
in Europe, for NIB magnets, sculptures, other items - lots of stuff!
Radio
Shack
for electronic
parts, kits, a few magnets
Digi-Key for
electronic components, Hall-effect sensors, etc.
CZFerro
for ferrofluid and kits
Marlin
P. Jones & Assoc.
www.amazing1.com/voltage.htm
for some great high voltage kits
www.magnets.com for
refrigerator magnets
OfficePlayground
for executive toys and wooden toys and magnetic toys
Grand
Illusions for magnetic and other types of toys
VAT19 Shop
of Curiously Awesome Gifts
eNASCO
catalog for educational supplies
Hall Effect Devices:
Radio Shack no longer carries these devices.
However, they are made by Allegro and are available from two other sources.
General information about the Allegro Hall Effect Devices can be found here:
http://www.allegromicro.com/en/Products/Categories/Sensors/linear.asp
They make several types of devices, but these fall into the
category of "Linear Hall-Effect Sensors".
An excellent Application Note can be found at
http://www.datasheetarchive.com/AN27702-datasheet.html
It will give you a good understanding of how they work, how they are used, and
some of their limitations.
I would recommend their P/N A1302 which has a sensitivity of
1.3mV/G. With this, you will be able to measure fields about as strong as
1690 Gauss which is good for permanent magnets.
The datasheet for this device is found at http://www.allegromicro.com/en/Products/Part_Numbers/1301/1301.pdf
Some other information you should consider.
1. The package that is easiest to work with is called the SIP (Single
In-line Package). It looks like this:
This allows you to easily plug it into a socket or into a
breadboard. This package has the suffix "UA" in the full part
number string.
2. The other package, with the suffix "LH", is
for surface mounting, called SMD (Surface Mount Device), and is very
small. Do NOT buy this. It looks like this:
This package is a little less than 0.30" in length, and the leads don't extend very far. Not useful for breadboards.
3. These devices also come with two temperature ranges
over which they are designed to operate.
The temp range of -40C to +85C is called the industrial
range, and uses the suffix "E" in its part number string. This
is less expensive.
The temp range of -40C to +125C is called the automotive
range, and uses the suffix "K" in its part number string. This
is more expensive and may have a longer lead-time (time between when
you order it and when they can ship it - could be 60 days, 120 days, etc).
All you need is the industrial temperature range.
4. This means that what you want is their part number "A1302EUA-T". The "-T" at the end of the part number means no lead (Pb) was used in the manufacturing of that part. An alternate part number is "A1302KUA-T" which will be a little more expensive but would also work well.
5. Newark usually has thousands of "A1302EUA-T" available as their P/N 31K6639 and can be found here:
Older information is below:
http://www.newark.com/allegro-microsystems/a1302eua-t/hall-effect-sensor-ic/dp/31K6639?_requestid=172713
They may also have "A1302KUA-T"available as their
P/N 31K6641 found here:
http://www.newark.com/allegro-microsystems/a1302kua-t/hall-effect-sensor-ic/dp/31K6641
How do you order it? One way is to give them a call at 1.800.4.NEWARK
(1.800.463.9275).
Another way is to register with them on-line at https://www.newark.com/jsp/profile/register.jsp?fromPage=true
and order on-line.
6. Another supplier is Digi-Key at http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=620-1022-ND
.
Cost is a little higher because of the temperature
range. They don't seem to carry the A1302EUA-T.
Contact them at: 
7. As a last resort, I would contact Allegro directly,
or one of their representatives, and try to obtain 2 of them as samples, or buy
them. Don't buy just one. Get two or three. They only cost
about $1 each, and if you overheat one, or plug it in backwards, or your dog
eats it - you'll have a spare.
Tell them what kind of project you are working on, and that you'd like 2 or 3 to
try as samples, or to buy.
8. If you need to measure weaker fields, there are other
sensitivities that are available.
A1302 has a sensitivity of 1.3mV/G. You will be able to measure a magnetic
field about as strong as 1690 Gauss with that.
A1301 and A1323 have a sensitivity of 2.5mV/G. You will be able to measure
a magnetic field about as strong as 880 Gauss with them.
A1321 has a sensitivity of 5.0mV/G. You will be able to measure a magnetic
field about as strong as 440 Gauss with that.
Earth's magnetic field is only 0.5 Gauss, and is not easy to measure and is
influenced by a lot of things.
So, you can pick the one you are most interested in. I found that the
A1302 works very well for most permanent magnet experiments.
Some magnets, motors, aluminum tubes, plug-in power supplies, other
odds and ends:There is paint available that can be used to paint a plaster wallboard, or other surface to which magnets normally don't stick. Contained in the paint are small iron particles that allow magnets to stick to whatever surface is coated with this paint. I know of two companies that make this: Krylon (I found this at Ace Hardware), and http://magnamagic.com/products/magnetic-receptive-chalkboard-paint.
Hardware, screws, tee-nuts, stainless steel screws and bolts,
shelving boards, metal plates (aluminum, brass, copper):
Menards Hardware or Handy Andy or Home Depot
Ace
Hardware
True
Value Hardware
Copper bars and plates:
Central
Steel & Wire Co.
Cool Toys:
Arabesk
(no longer active)
The
Nature Company
The
Museum of Science and Industry
Shop
for Science
www.toymagnets.com
www.mindfulgroup.com
www.supermagnete.de/?adwords3
interesting sculptures
Software for simulating magnetic and electromagnetic fields:
Ansoft Corporation
no longer has their FREE Student
Version of their 2D Maxwell program available on-line.
Here is a basic user manual
I wrote to help you step through the software if you have it.
Simplorer software for
simulating electrical circuits, FREE
Student
Version available!!
Formulas used
for solving magnetic problems
Infolytica
software - great examples!
For books and videos about magnets and magnetism, go to BOOKS.