Telephone status indicator with LED
This will monitor telephone status without loading the telephone line, this way if you have two phones in parallel you will know if one of them is busy. Connect the two ends of circuit...
This will monitor telephone status without loading the telephone line, this way if you have two phones in parallel you will know if one of them is busy. Connect the two ends of circuit...
This circuit is a standard way of driving Small Power Relays from Control Signals generated by Logic or Opamp Circuits. C2 and R5 form a snubber which improves the life of the metal contacts,...