It has been over a century and a half since Alexander Graham Bell whispered the words ‘Mary had a little lamb’ and changed the way mankind communicated. Modern life is unimaginable without a telephonic device—be it a sophisticated cell phone or an archaic pulse dial telephone still in use in certain parts of India. If you have gone fully digital, don’t thrown out your land line instruments in a hurry. This workshop will help you make a functional small distance intercom device.

View the full procedure : Here