Wireless telegraph receivers

Improvements in wireless telegraph receivers have been much more numerous than in the sending apparatus. Since the first detector of Hertz, consisting of a minute spark-gap and loop of wire, used in 1887, there has been a very marked improvement. This improvement has not extended to the sending apparatus, for this apparatus is practically the same to-day as that employed by Hertz, differing mostly in magnitude and in the fact that one side of the oscillator is connected to ground.