This circuit was found in a Popular Electronics from the 90s. The transistors are general purpose, and the gain depends on the ratio between R2 and R1.
This 50% active cycle TTL clock generates signals from 4 to 20 Hz. Its power must be supplied with 5 V...
This circuit already explored in several diagrams in this section was found in a 90’s Popular...
In the figure we show a circuit in which the output voltage of a 78XX voltage regulator is...