We found this battery eliminator in a Radio Electronics magazine from August 1974. The transistor must be equipped with a heatsink and other voltages can be achieved by replacing the zener.
This micro AM radio will tune strong stations in the frequency range between 530 and 1,600 kHz....
This circuit was obtained in a Electronics World of 1968. The transistors can be equivalent as the BC558...
Based on an integrated circuit of the time, this circuit appeared in the October 1979 issue of...