When I was in the Navy years ago we used cordless head phones with no batteries. I cant for the life of me remember how they worked. I would google but i would rather ask here.
thanks in advance.
by the way this was inspired by the 60’s mobile phone thread.
Cordless?
I remember “sound powered phones” that required no electricity or batteries, but still pluged into a jack. It was a closed loop that anybody else on that loop could talk also. Like an old telephone party line.
Of course you are right. But did it get its power from the jack?
Sorry, I get foggier by the day.
Sound powered phones get their power from the user’s voice. More than you ever wanted to know: Wikipedia entry