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无线电通信起源于 19世纪，到 20世纪初的 1906年，科学家才发现了一种较为理想的可作高频振荡和检波的矿石材料，这就是矿石检波器，从而导致了第一代矿石收音机的诞生。不过它功率小，性能差，还只能供个人用耳机收听。 1919年，超外差式电子管收音机研制成功，具有音频优?
Radio communications originated in the 19th century and by early twentieth century in 1906 scientists discovered an ideal ore material for high-frequency oscillation and detection. This was the ore detector, which led to the first generation of ore radio Birth. However, its power, poor performance, but also for personal use headphones to listen. 1919, superheterodyne tube radio successfully developed, with excellent audio?