This simple audio and RF signal tracker was found in a Japanese publication in 1967. The transistors are made of germanium and the headphone is made of crystal.
Found in a 90s documentation, this switch that is also sensitive enough to operate capacitively uses...
This circuit was found in an integrated circuit manual from the 1980s. The circuit can be designed...
This powerful and sophisticated power supply was found in a 1998 publication. The circuit must...