This game was found in Radio Electronics from the 90s. The components used are common except some that are from that time and that can no longer be found easily.
This simple metal detector was found in a 1960 Sylvania transistor manual. The phone must be high...
This is one of the many versions of this type of indicator that the reader can find on our...
Found in an English publication from the 1980s, this circuit can be built with equivalent...