安没有彩色电视机，是吗？
他于1939年获准的彩电接收机线路的专利一直延续到1971年，因为在当时这项专利期内没有彩色电视节目可以接收，因此专利无望被采用。
His 1939 patent for color TV receiver circuitry was extended until 1971 because for most of the patent 's normal life there was no colour TV to receive and thus no hope of reward for the invention.
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