Assertion: radio's use | /r/HasProperty | pioneered by lee de forest
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text: The use of amplitude modulation (AM), by which soundwaves can be transmitted over a continuous-wave radio signal of narrow bandwidth (as opposed to spark-gap radio, which sent rapid strings of damped-wave pulses that consumed lots of bandwidth and were only suitable for Morse-code telegraphy) was pioneered by Fessenden and Lee de Forest.