Phone message light

Thread Starter


Joined Jun 10, 2010
Hello I want to use the blinking message light on our company phone to power a relay so I can light up 120v lights in the shop. I tried using a transistor but I think there is not enough amperage to drive the relay. The relay is .5a . I have been reading that an optocoupler might be the answer. Any help would be appreciated


Joined Sep 26, 2009
an opto coupler would work, you just need to replace the LED on the message display and connect the LED side of the optocoupler in its place (if the ratings for the optocoupler LED is the same for the current LED), then use the transistor side of the optocoupler to switch on a relay which in turn will switch the AC load for the shop lights, just make sure the relay contacts are rated to handle the load of the 120V lights....

B. Morse