When a terrestrial channel transmits a nicam signal to your TV, it decodes it and gives you stereo. When you add a video, the RF cable is plugged into the VCR and a fly lead to the TV. The video will pass the nicam signal to the TV and so you can watch to nicam program on UHF rather than having the VCR turned on and the TV AV1 selected. In a collegues VCR manual it says *during playback* to listen to nicam sound you must use a scart connecter. Why is that?