When a frequency modulation (FM) receiver does not receive a signal, it outputs strong noise. This noise is formed by the random frequency variations of antenna background noise and internal circuit noise after frequency discrimination and is independent of the background noise amplitude received by the antenna.
调频接收机没有接收到信号时，会输出强烈的噪声。关于这种噪声的描述是：由天线背景噪声和机内电路噪声的随机频率变化经鉴频形成，其大小与天线接收到的背景噪声幅度无关。
| 正面 | LK0790 调频接收机没有接收到信号时，会输出强烈的噪声。关于这种噪声的描述是： |
|---|---|
| 背面 | 由天线背景噪声和机内电路噪声的随机频率变化经鉴频形成，其大小与天线接收到的背景噪声幅度无关 |
Tags: 故障, 调制, 调频
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