These items are used to determine the frequency of A.C. mains by
sonometer method. This apparatus consists of a suitable electromagnet
with step down transformer affixed voltages 6V & 8V and has a
current capacity 2A. When this attachment is supported over a Sonometer
and connected to a source of alternating current, the wire
vibrates continuously. By adjusting the tension and the bridge position
maximum resonance can be obtained. Supplied without Sonometer
and without stand for holding the electromagnet.
