From the point of view of the power supply the audio amplifiers are generally of two types. The first type is used mainly in applications with a single power supply. Some can be used with a dual power ...

This multi-tone siren is useful for burglar alarms, reverse horns, etc. It produces five different audio tones and is much more ear-catching than a single-tone siren. The circuit is built around ...

Once ubiquitous, the incandescent light bulb has become something of a lucerna non grata lately. Banned from home lighting, long gone from flashlights, and laughed out of existence by automotive ...