Found in the June 1987 issue of Radio Electronics magazine, this circuit uses well-known CMOS components. The circuit has a CMOS amplifier stage that drives a small speaker.
This Japanese radio is from the 60s, presenting excellent sensitivity and an output power of 100mW...
Found in a Popular Electronics from the 90s, this circuit uses components that are still current....
This circuit consists of a simple capacitance bridge. The handset can be high impedance from 500...