Found in an Electronic Design and 1970s, this circuit uses transistors of the time. The transistors can be replaced with equivalents and the relay is 12 V depending on the power supply.
This circuit converts square (rectangular) signals into triangular signals with typical 16 V...
This simple transistorized game that appears in other versions in this section and website, was...
This circuit has as a critical component the transformer that has low voltage windings for the...