This receiver was found in a Japanese publication in 1967. The circuit uses germanium transistors and details of the coils are not given. Power is supplied by a 9 V battery.
This circuit causes an LED to flash at a frequency determined by the capacitor. The circuit has an...
Found in American documentation from the 1980s, this circuit uses transistors from that time. It...
This very interesting project was obtained in a 1980 publication. It consists of a device that is...