Found in General Electric documentation from the 1980s, this circuit generates signals that depend on the values of the components given in the table next to the diagram.
This receiver for listening on the phone was found in a Japanese magazine in 1967. The circuit uses...
This receiver circuit was found in a Hands On Electronics from the 90s. The circuit uses a PLL...
This transistorized siren was found in the patent section of Radio Electronics magazine from March...