Radio is "free to air," and so is much of television.

无线广播“免费播送”，许多电视也是如此。

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Get your free personal radio channel recorder on the Internet with the possibility to record from hundreds of radio channels.

从互联网上获得你免费个人电台录音，可以记录网络上数百个电台。

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Mixcloud (mixcloud.com) lets you listen to free radio shows, DJ mixes and podcasts on demand.

Mixcloud（mixcloud.com）让你免费点播电台演播，DJ曲和博客。

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Slacker has three complementary service tiers, from the entirely free Slacker Basic Radio and the ad-free Slacker Radio Plus to the on-demand access of Slacker Premium Radio.

ENGADGET: Slacker now streaming six ESPN stations, Radio and Deportes amongst them

In the days when what is now called terrestrial radio -- that is, free radio, broadcast by local stations -- ruled, you couldn't help hearing his voice as you twisted the dial through the stations in your town.

CNN: Billy Graham's other voice

It's too early to tell if subscriber gains are attributable to all this expensive new content, or if the real draw for satellite radio is commercial-free, unique music.

FORBES: Satellite Radio Days