Found in an Elektor from the 90s, this circuit converts signals from the 280 kHz band to 516 kHz, making it possible to tune them in common AM radios. The components used are from that time.
This circuit was obtained in a 1978 English magazine. This adjustable stabilized power source...
This circuit was found in old documentation, but as it uses the 555 it can still be easily...
This timer with field effect transistors was obtained from Fairchild documentation. The times...