This primitive solar radio was found in a Gernsback publication from 1960. The transistor is made of germanium of the time and the earphone is magnetic with high impedance.
The circuit shown is suggested by National Semiconductor in its 1994 Linear Applications Handbook. We...
The ZN416E integrated circuit is uncommon today. It consists of a complete radio, like the one...
In the figure we show how to implement a voltage reference with the ON Semiconductor rail-to-rail...