Schematic of Magnetic Ball Levitator

Parts List for the Magnetic Ball Levitator

SEMICONDUCTORS
IC1	LM7812 l2-volt regulator, integrated circuit
IC2	LM324 quad op-amp, integrated circuit
Q1	IRF510 MOSFET transistor
Q2	NPN phototransistor (Radio Shack 276-145 or equivalent)
LED1	Infrared light-emitting diode (Radio Shack 276-142 or equivalent)
BR1	Full-wave bridge rectifier, 4-ampere, 50-PIV
Dl	GI750 silicon rectifier diode (can be substituted by any 4-ampere, 50-volt unit)

RESISTORS
(All fixed resistors are ¼-watt, 5% units, except where otherwise noted)
Rl, R3, R5	10,000-ohm
R2	10,000-ohm potentiometer
R4	270-ohm
R6	50,000-ohm potentiometer
R7	0.47-ohm, 5-watt, 10%
R8	1OOO-ohm
CAPACITORS
C1	10-µF 50-WVDC, electrolytic
C2	1µF, 5O-WVDC, electrolytic
C3	5900-µF 30-WVDC, electrolytic
C4	3.3µF, 5O-WVDC, electrolytic
ADDITIONAL PARTS AND MATERIALS
L1	Magnet coil (see text)
T1	117-VAC to 25-VAC, 2-ampere power transformer
M1	DC voltmeter, 0- to 15-volt range
F1	Thermal-protector fuse (Radio Shack 270-1322 or equivalent)
F2	1-ampere fuse
PL1	6-connector power plug
PL2	2-termina1 AC plug
SO1	6-connector power socket
S1	SPST switch
	Perforated board
	Project enclosure
	Metal globe
	SIP socket
	2 orange juice can lids
	Heat sink measuring 3 X 4 X 1½ inches (JDR Microdevices HS192OOOB or equivalent)
	½-inch-diameter PVC tubing
	1-inch-diameter PVC coupling
	2-inch-long l0-24 bolts
	Magnet-core nail (12-inches long by 3/4-inch diameter)
	Metal epoxy
	Magnet pin (3/4-inch length of coathanger wire)
	Washer
	520 feet of 22-gauge magnet wire
	Power cord, wire, solder, hardware, etc.

This article is reprinted from Popular Electronics, May 1996.

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