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 DC / DC converter was found in an American 1980s documentation. It provides a negative...
We found this circuit in a 1987 documentation. It is a multi-tester with neon lamp and LEDs...
Found in a 90s Practical Wireless, this circuit provides 8 to 10 W of output with a gain of 14 dB....