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前不久,笔者购买了一台德生牌R9700型12波段收音机,它具有电视伴音功能,效果还不错。它采用了短波二次变频接收技术,此技术常用于军事和民用通信领域,如短波收信机和蜂窝式移动电话,目的是提高接收灵敏度、选择性和抗干扰能力。该收音机从机壳样式和做工方面都体现得很
Not long ago, I bought a German students R9700 12-band radio, it has a TV sound function, the effect is not bad. It uses a short-wave two-frequency conversion receive technology, this technology is commonly used in military and civilian communications, such as short-wave receivers and cellular mobile phones, the purpose is to improve receiver sensitivity, selectivity and anti-interference ability. The radio from the chassis style and workmanship are reflected