This circuit was obtained from a 1978 Practical Wireless. It makes a speaker emit sound when there is continuity of the circuit under test. The circuit is ultra low power and can be powered by a single battery for months.
This circuit was obtained from a 1978 Practical Wireless. It makes a speaker emit sound when there is continuity of the circuit under test. The circuit is ultra low power and can be powered by a single battery for months.
