analog signal

基本解释

Composite: The yellow video cable that connects old-fashioned analog signal into televisions.
复合(composite): 一种黄色视频线，可以把老式模拟信号接入电视机。
It is hard to convey the difference between a DTV signal and an analog signal without an actual demonstration, but here is a static comparison that can help you understand the idea.
没有实际电视演示的情况下很难将数字/模拟信号的差别表达清楚。
The set-top box does receive a digital signal from the satellite or cable; but once received, the signal is converted to an analog signal and sent to your analog TV on channel 3 or 4.
机顶盒确实从卫星或有线电视电缆接收数字信号；但它随之将其变为模拟信号并送到你的模拟电视的3或4频道。

Community Relations Director Ann Curran says her network will have to cut programming to keep its analog signal on the air.
NPR: TV Stations Say Digital Switch Delay Will Be Costly
Moreover, with digital you can also move that information around without losing it in the surrounding noise, as this often happens with an analog signal.
FORBES: Computing Desire
When Sehat was 12, he taught himself analog signal processing by taking apart his family's Philips six-transistor radio and rebuilding it one component at a time.
FORBES: Magazine Article

模拟信号
How to convert analog signal to digital signal is the crux of the matter.
模拟信号的数字化是系统的关键部分。
模拟量
类比信号