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使不得，使不得。美国人发明了技术，日本用它来赚了钱，后来中国人学会了，于是大家都穷了。但是大家都有设备用了。：）
'美国人edwin armstrong发明了超外差技术。现代的收音机、收发信机、雷达、电视机都是基于他发明的这个技术。不知道k3是火花式还是矿石式的？如果是超外差，有芯片，就是美国技术，bg8cih一定看了不少书
下面是有关edwin armstrong的文字：
armstrong, edwin howard (dec. 18, 1890 -- jan. 31, 1954), electrical engineer and inventor of three of the basic electronic circuits underlying all modern radio, radar, and television, was born in new york city, the first child of john and emily smith armstrong, both native new yorkers. his mother had been a teacher in the public schools and his father was vice president of the united states branch of the oxford university press. the family soon moved to the suburban town of yonkers, n.y., where they lived in a house on a bluff overlooking the hudson river.
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http://users.erols.com/oldradio/ehabio.htm）
