| 摘要 |
<p>A signal mixing circuit for blending two signals, such as left and right channel FM stereo signals, blends the two signals at each of two outputs in response to a variable control voltage, which acts upon a transistor network connected between the two signal paths. When the variable control voltage is determined by an amplitude detector connected in a conventional FM stereo receiver, the output signals will be blended to a greater degree when the received signal strength of the broadcast FM signal becomes weaker. In a further embodiment, capacitors are added to inhibit high-frequency components of one channel and to add in high-frequency components of another channel thereby eliminating and canceling the noise components normally present in the respective signals and improving the S/N ratio.</p> |
