Same line automatic recording appender circuit diagram

The same-line automatic recording adapter circuit is shown in the figure below. The same-line automatic recording adapter can be easily used on different types of domestic and foreign recording telephones and answering machines. Due to the limitations of the power supply and volume of the original machine, it is best to choose small and sensitive relays, such as Nissan SV-5 and M4-5. It is best to install this device on a fully automatic tape recording telephone. The modification effect is not obvious on an IC language chip type recording telephone.