This circuit allows you to simulate an analog telephone line for the repair and testing of devices. The circuit is from 1994 and all the components used are common.
Simple timers can be designed using inverters or any other gate that can be connected as inverter. Figure...
Found in the Encyclopedia of Electronic Circuits volume 5 from 1995, this circuit uses a...
Found in a 1980s telecommunications documentation, the circuit presented acts as a product...