This sensitive bio-monitoring circuit was found in the December 1984 issue of Radio Electronics magazine. The circuit is powered by a 9 V battery and uses a low-impedance headphone output.
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...