This circuit was found in a Modern Transistor Workbook from 1965. The circuit sends signals from a small record player to a medium-wave radio placed nearby.
This circuit was obtained in the manual of the used integrated circuit. Equivalents may be used...
The UVTRON tube is an ultraviolet radiation sensor. In this circuit from Radio Electronics from...
This circuit was suggested by Popular Elecronics from the 90's. The circuit has high input...