This circuit is for traditional old-style telephone lines found in an American 1980s documentation. Components are common and the optical coupler can be replaced with an equivalent.
This soft start circuit was found in a 1965 General Electric documentation. The SCR and bridge...
This circuit charges a battery to power a flashlight at night. The circuit is from an English...
This RCA / GE circuit from the 90s can be applied to any modern operational amplifier. The number...