This circuit that generates a special sound was found in a Popular Electronics from the 90s. The base is the 555 and the transistors admit equivalents, and a power stage can be added.
This temperature compensated circuit was found in a Popular Electronics of the 1990s. The circuit...
Using period transistors, this 10 W amplifier was found in Radio Electronics magazine from May...
This PUT trigger circuit for SCR was found in 1967 General Electric documentation. The...