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国内首家金融信息电台——浙江金融信息广播电台,11月1日在杭州开播,它是利用浙江经济广播电台94.8兆赫调频立体声的附加信道(SCA)进行广播的。 1958年,美国FCC批准调频电台可以开办用户付费收听的SCA广播,最初在67kHz调频副载频信号上插入频率调制的摸拟声音,主要用于语言、音乐广播,带宽只有12kHz。1983年4月,美国FCC放宽了对SCA业务的限制,允许调频台使用一个以上的副载频,如使用67和92kHz的双副载频,基带由20Hz～75kHz扩展到20Hz～99kHz,带宽从12kHz展宽到20kHz和40kHz,
The first financial information radio station in China, Zhejiang Financial Information Broadcasting Station, was launched on November 1 in Hangzhou. It was broadcast using Zhejiang Economic Radio’s 94.8 MHz FM stereo additional channel (SCA). In 1958, the United States FCC approved the FM radio SCA radio users can pay to start listening, initially in the 67kHz FM subcarrier signal to insert the frequency modulation of the analog sound, mainly for speech and music broadcast, the bandwidth is only 12kHz. In April 1983, the U.S. FCC relaxed its restrictions on SCA services by allowing the FM station to use more than one subcarrier, such as using dual-subcarrier frequencies of 67 and 92 kHz. The baseband was extended from 20 Hz to 75 kHz to 20 Hz to 99 kHz with bandwidth ranging from 12kHz widened to 20kHz and 40kHz,