This circuit was found in Radio Electronics from the 90s. The components used are common, and the transistors and CIs must be equipped with heat sinks.
This interesting source of very low voltage for reference finds applications in the...
This sonic switch, sound relay or simply vox uses a medium impedance speaker as a microphone. The...
Using red LEDs with ignition voltages of the order of 1.5 V we can make a multiple voltage...