This RIAA equalizer preamp was found in a 1990s schematic. The transistors are an old version of the BC549 that can be used as a replacement. Signal input and output cable must be shielded.
This busy line indicator is very simple, serving for analog lines. The supply is made by two...
This circuit was found in an 80's Electronic Engineering. The circuit uses operatives of the time...
Other operational amplifiers series, such as the MC34072, MC34074, MC35071, MC35072, MC35074 d...