This circuit provides a signal when dialing occurs. The circuit is powered by the telephone line voltage itself. We found it in an old documentation.
This circuit is from a 1976 publication. The circuit formed by L1 and C1 must be designed...
The resistors R1 and R2 consist of 8 220 ohms x 2 W resistors connected in parallel. The...
In the figure we present a circuit of a signal conditioner for microphone using the integrated circuit...