TeachSpin's HE1-A Hall Effect Probe is a rugged and versatile device that produces a low impedance output voltage directly proportional to the magnetic field at its sensors. It can measure both the radial and transverse components of the field at a given region of space. It can measure both constant and low frequency alternating magnetic fields. The HE1-A is a high sensitivity device capable of measuring the magnetic field created by a 10 ampere current flowing in a long straight wire at a radial distance of up to one half meter.

The probe has two gain settings that give the instrument a large dynamic range. It has a linear response to better than 0.1% over the entire range. The manual zero adjust allows the operator to set the output voltage to zero in the local ambient Earth's magnetic field. HE1-A has its own power supply that plugs directly into a standard wall outlet of 110VAC. An analog or digital voltmeter is needed to determine the output of the probe. TeachSpin recommends a digital voltmeter capable of measuring millivolts, since the instrument has a maximum sensitivity of about 10-3 mT/mV and a voltage stability of 2mV. The maximum output is +/- 11 volts. 
 

HE1-A is not calibrated. The job of calibration is left as an exercise for the student or it can be done by the teacher. We recommend using a Helmholtz pair, such as the one provided with TeachSpin's "Magnetic Force" since the field is very uniform in the central region between the two coils. Data set 1 is a typical calibration curve using our MF1-A coils. Data set 2 shows the magnetic field as a function of radial distance from a long straight wire carrying 10 amperes of current.
The probe is available with a handsome non-magnetic stand made of hardwood, aluminum and brass components. The probe has a built in ring stand clamp made of aluminum with nylon thumb screws. As with all of TeachSpin's instruments, HE1-A is warranted for two years.