Jan Miller said, "I don't believe it!"
Rick had to laugh. "I'm not sure I do, either. But let's try." He sat down at the table and held the receiver to his ear. With the other hand he began the laborious job of locating a sensitive spot on the razor blade.
Dr. Gordon had told him that only an occasional spot on a blade will work. Some blades have no such spots. Others have many.
Rick was beginning to think that he had one of the no-spot kind, or that the whole idea was wrong, when he heard what he thought was a voice. He hastily concentrated on the spot, and in a few seconds music flooded into the earphone. He had caught a disk jockey in the process of introducing a record. For a long moment he listened, then held out the earphone with a broad grin. "Anyone care to listen?"
Everyone did. They took turns, with each application of the phone to an ear accompanied by expressions of astonishment.
Barby looked at her brother with new respect. "It's just fantastic! How on earth does it work?"
Dr. Miller chuckled. "I'm sure you don't want a full course in electronics, Barby. Actually, it's simple enough. The signal from the radio station is an alternating current that sets up a corresponding current in the antenna wire. This current goes through the coil and is rectified—that is, it's turned into pulsating direct current—by the razor blade. The receiver then converts it into audible sound."
Barby sighed. "I'll just have to take your word for it. But it's a miracle!"
"It may seem like one, but it's really the same kind of circuit you find in a crystal set," Rick explained. "The razor blade acts like the crystal. That's all."
The young people took turns listening to the station, located in a town nearby. Within the hour there was a weather report promising clearing skies before the end of the day. Later, in a roundup of local announcements, they heard that the annual Sons of the Old Dominion feast, postponed because of the storm, would be held the next night.