This circuit was found in a 1970s General Electric documentation. This circuit already used an emitting LED. The circuit operates at frequencies from 50 Hz to 50 kHz with short pulses
The oscillator in the figure has its frequency determined by the crystal. The indicated value is...
Found in an American publication from the 90s, this circuit allows the supply of 3, 6 and 9 V...
This circuit was found in an application note of the Linear Technology LTC1145. The circuit can be used...