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What it seems like is that your DVD recorder is picking up the few analogue channels that are carried by cable TV provider. Unfortunately, DVD recorders will not tune in encrypted or digital cable TV channels.
To record from a digital or encrypted channel, you need to switch to this channel on your cable TV receiver and record from the input source this is connected to on your DVD recorder. For example, if you have the 2nd AV connection of your cable box connected to the "Input1" jacks of your DVD recorder, when setting up a timer, you select "Input1" as the recording source and leave the cable box on the channel you will be recording.