This is simple telephone locator-light which is used to identify the ringing telephone at the night / low light conditions. This unit only activates at low light conditions and it automatically turns off lights after 12 - 15 sec. from last ring.

This telephone locator is mainly based on NE555 time IC and it is design to work with 6V 0.5A - 1A power source. This given schematic support maximum of two 3W power LEDs. During the assembly it is important to place both LEDs and LDR in two separate positions to avoid any interference to LDR from LEDs.

Also note that in some counties it is illegal to connect custom circuitry into phone lines, please check your local regulatory bodies if concerned.

Project Related Downloads


Schematic and PCB designs of Simple Telephone Locator Light Project.

References


NE555 - General-Purpose Single Bipolar Timer.
PC817 - Optocoupler
KSE800 - 60V 4A Darlington NPN Transistor