This circuit was obtained from a 1967 General Electric manual. The circuit makes use of absolutely current components. Similar versions from other sources can be found in this section.
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...