This circuit was found in a British documentation from 1969. It can be implemented with modern transistors. The pass band is 6 MHz.
This an old commercial receiver found in a year 1958 magazine. The circuit uses some transformer...
Found in an English publication from 1967, this circuit generates 5 kHz signals with harmonics that...
This circuit was found in a 1999 British magazine (ETI). It is a device that receives the signal...