Gives a localised, precision receiver which finds particular application in identifying areas of peak and low amplitude in interference, reflection and refraction experiments.

Utilizes a Schottky diode oscillator module feeding a tuned waveguide and horn to give a directional microwave beam. The beam is modulated with a variable frequency audio signal which can be adjusted by the control on the top panel.

Instead of a one-off demonstration use the mini-sonometer to give your students hands-on experience of sound production.
The apparatus is constructed on an acrylic base with hardwood sides measuring 650 × 100mm overall. It has an integral pulley, wire clamp and half metre scale.