Air Mail Radio

The General Electric Co. announced that Postmaster General New has ordered all mail planes to be equipped with special radio sending and receiving sets. Pilots can converse with land stations, get their bearings in rain, fog or night, find out the weather ahead of them, summon help in case of emergency landings. Exhaustive tests show that the equipment will work even when thoroughly saturated with rain or snow.

The operation of the set is simple --as it must be for a man piloting an airplane, who has to receive or send messages while continuing his trip. Throwing a switch and turning a large knob till an ammeter on the dashboard shows a maximum reading is the whole tuning up process. A motor generator set, driven by a storage battery which the engine charges just as an automobile does, supplies the necessary pressure of 1,000 volts. Two hundred feet of trailing wire, let out when the plane leaves the ground, constitutes the antenna.