Sound Sense provides teachers with a versatile apparatus for exploring the properties of thermistors, LDRs, and resistors in general. It contains an electronic unit which gives an audible note through an integral loudspeaker whose pitch can be controlled by a resistor. All connections are by 4mm sockets and the output can be fed to an oscilloscope for frequency measurement. The unit allows students to carry out investigations such as frequency / light intensity, frequency / temperature etc as well as having an original aid for oscilloscope studies. Power is provided by any bench d.c. PSU up to 12V. There is a mute switch for the loudspeaker. All contained in an attractive, transparent, blue enclosure. Dimensions 130 x 70 x 40mm.