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.
This circuit consists of a power audio amplifier used in the modulation of AM transmitters. The...
This circuit was found in National Semiconductor documentation from the 1990s. The circuit has a 75...
When switching on, the output voltage of this regulator rises slowly until it reaches 15 V. The...