I still remember watching WW2 films and seeing scenes of phone exchanges where people were switching manually ussing the quarter inch jack. It was surprisingly

I still remember watching WW2 films and seeing scenes of phone exchanges where people were switching manually ussing the quarter inch jack. It was surprisingly thrilling. I was working during the day at a place where I sold the same type of jack that was in use for similar purposes all the way back in world war 2. I had no idea their history went back so much further than that.