Found in Radio Electronics magazine from 1959, this high-fidelity amplifier has 15 W of power. Power supply was not provided.
Found in an old Popular Electronics this circuit is still current. The SCR can be of the 106...
Found in a 1968 EEE, this circuit accepts frequencies from 1 to 1000 Hz and control voltages from 0.1 to...
This is the basic configuration of a voltage-controlled oscillator using the PLL 4046. The circuit...