Today's picture is from 1924, and it shows the first clock radio. No, it did not play music, the radio was for remotely setting the clock. Back before high speed communication, a real problem was there was no way to synchronize clocks and timekeeping in different location. Two towns miles apart, might be working on two different clocks. What one town said was noon might be 12:30 in the next town over. This actually caused quiet a bit of trouble for train travel. The device above had a radio receiver, and hence all such clocks could be set via radio waves from a central location, helping to synchronize clocks over a vast area. All clocks did not have to be like the one above, but if each town had such a clock, others could set their watch from it.