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.
We found this circuit in an old American publication. It can be mounted with TIC106 type SCRs and...
This simple circuit has good gain and can be implemented with any general-purpose transistor. The...
This circuit was obtained from an Application Note from Linear Technology that manufactures the used...