Found in a 1966 American publication, this circuit generates a 25 MHz rectangular signal for testing flip-flops. Transistors are from the era. No information is given about L1.
The figure shows how to obtain a capacitance digitally with 4066 switches. The table shows the...
Found in an old Popular Electronics this circuit is still current. The SCR can be of the 106...
Found in a 90s Popular Electronics, this circuit uses common components. The power transistors can be...