Dynamic compressor (CB21762E)

This circuit was found in a 1977 publication for radio amateurs. Transistors are common general-purpose types of the time.

Unijunction Alarm Siren (CB19990E)
This circuit is from an American documentation from 1975. The single junction transistors can be...
500 nW amplifier with the LM4250 (CB14173E)
This circuit, suggested by the Linear Applications Handbook of National Semiconductor, uses a very...
Symmetric Power Source Up To 3 A Divider L165 (CB15142E)
This circuit divides the voltage of a source by 2, allowing its use as a symmetrical source. In...