Found in a European magazine from the 90s, this circuit emits beeps that are several seconds apart to indicate that a device is on. The transducer is a ceramic or crystal capsule.
This high input impedance circuit was found in American documentation from the 1980s. The power...
This circuit shows on the screen of an oscilloscope two signals alternately at a frequency that depends...
This circuit transmits the signal taken from a telephone line to a receiver placed nearby (up to a...