The answers to the original posterâ€™s questions depend upon a number of factors.
In the DVD recorder the type of signal (antenna or cable) has to selected and a channel scan must be completed. The clock must also be set. Then scheduled recordings may be entered by selecting the output channel of the cable box (usually channel 3) as the recording channel or selecting the Input where the cable box is connected as the input to be recorded.
The main considerations are also related to certain design characteristics of the DVD Recorder or combo recorder and the way this device is interconnected with other equipment and the TV. There are different answers depending upon whether the DVD recorder is providing the TV with its cable signal through the cable coax or is providing a signal through another input on the TV.
If the DVD recorder receives its cable signal from the cable box (or, say a satellite receiver) through inputs with yellow, white and red cables (termed “composite” cables) and/or through a S-Video cable, and outputs its signal to the TV with those same type of “output” cables, or red, green and blue cables (termed “component” cables) and/or a HDMI cable, the answer is that one may be able watch other programming while copying videotaped recordings to DVD. In this instance it is a matter of switching inputs on the TV remote control.
If the DVD recorder receives its cable signal from the cable box (or, again, a satellite receiver) through the threaded RF coax “in” connector and outputs its signal to the TV through the threaded RF coax “out” connector one may not be able to watch other programming while copying videotaped recordings to DVD. In this instance the DVD recorder is directly in the tuning path and might not be switched out of that path for independent operation such as copying videotaped recordings to DVD and watching cable at the same time.
If the DVD recorder is connected to the TV through the RF coax one may wish to add a second output to the TV, either composite for video and audio or component for video and white/red for audio, (or some other connection) if the TV has such inputs, and then use the TV remote to switch between the inputs for setting up videotape copying and then switch back to the RF input to watch cable.
Most, if not all DVD combo recorders have a modulated RF output. This means that whatever signal is fed to the combo recorder’s RF input is passed through to the RF output unless the machine is playing a DVD or copying a videotaped recording to DVD, in which case that signal overrides the RF input signal from your cable box. In this case one will not be able to watch cable while copying a videotaped recording to DVD. The program being played or recorded will be the one present on the combo recorder outputs. The workaround is to insert a RF A/B switch (around $6) between the cable box and DVD combo recorder. One feed should go to the DVD combo recorder and the other feed should go to the TV’s RF input. The A/B switch selects between these feeds and will allow the cable signal to be passed through to the TV. The TV remote will select between the input signal sources allowing one to watch cable while the machine is recording a DVD.
Most recent model DVD recorders (without VHS sections) have unmodulated RF outputs. This means that whatever signal is fed to the DVD recorder’s RF input is passed through to its RF output. If the machine is playing or recording a DVD that signal is output only through the composite jacks (yellow, red and white), the component jacks (red, green and blue), S-Video jack, or HDMI jack (if present). Those outputs carry only the playing/recording output and the RF output continues to pass through whatever signal is fed to the DVD recorder’s RF input, thus allowing the TV remote to select between the signal sources allowing one to watch cable while the machine is recording from another input fed from an external VCR.