Cri "baby" Call
I found this at work, at first it looked like some kind of intercom but then I realised it is called a “Cri Call”. It is an old valve based baby monitor! What you do is screw the small box onto the wall in the babys room then trail a wire along your hallway to your living room to monitor the baby. Next test, put a guitar into it! it will definitely make a neat (tube!) practice amp.