This variable oscillator with power step for alarms was found in an American documentation from the 90's. The power transistor must be equipped with a heat sink.
This low impedance circuit was found in an Electronic Design from the 90's. Operational amplifiers admit...
This circuit makes use of an old operational one to generate clock signals that depend on the...
This basic version of the timer with the 555 was found in documentation from the 1980s. The relay...