This circuit was found in a 1964 Electronic Design. The circuit makes use of transistors of the time. Current equivalent transistors may be experienced.
This circuit can be applied to several logics. The circuit is from an Electronics Now from the...
This simple circuit with SCR and unijunction transistor appeared in Radio Electronics magazine in July...
This timer was found in a 1980 publication. With the BC548 for Q1, an 8-ohm speaker with 6 V power...