Using the NE5205 integrated circuit this circuit was found in the May 1987 issue of Radio Electronics magazine. It can amplify signals up to 450MHz.
8E) This siren was found in a 1989 documentation. It uses only transistors and includes two power...
We found this circuit, which appears with variations on this site, in a European documentation from the...
The operational amplifier used in this configuration is of an uncommon type today. The circuit can be...