Sony Trinitron KV-32FV27 Service Manual page 183

Installing the TV
To use PIP with the Cable Box
Turn on the cable box and VCR. Use the remote control's TV/VIDEO
(yellow) button to set the PIP output to VIDEO 1. Change the PIP
channel via the cable box. (The cable box's tuner is used as the
PIP video source; if you do not turn on the cable box, the PIP will
not work.)
This system is needed because the cable box unscrambles only one channel at
a time (unlike regular cable, which makes all channels available concurrently).
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