When the phone rings, a high-powered incandescent light comes on. This circuit can be interesting to obtain the remote call warning or to assist the hearing impaired.
This 6-transistor receiver was manufactured in Japan in the 60s. The circuit is superheterodyne and has a 6V...
This circuit was found in a 1986 documentation and it may be difficult to obtain some of its...
This circuit was found in a 1980s documentation. The low voltage circuit uses a PUT. Transistors can...