| The switching unit described here is capable of controlling up to seven mains-powered loads with the aid of commands received via telephon...
All items tagged with phone and Switch (13)
| Rectifying the buzzer signal on a telephone line results in a voltage that may be used to switch one or more loads, for instance, a light...
| elektor July/august 1985 Microphones, unfortunately, produce onlyasmallsignalandthey,therefore, require a special pre-amplifier to boost the...