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 is from a Radio Electronics magazine from October 1987. The Triac must be equipped with a...
The integrated circuit used is not common today and the voltage gain is unitary. The circuit is...
This source with two symmetrical output voltages was found in 90s Radio Electronics. The 22 V...