With a harddrive recorder like your Panasonic DMR-EX768EBS, the easiest way to use it is to record everything to the harddrive (not directly to DVD). The recorder will then record wherever there is room on the harddrive, and you don’t have to speculate about where it’s recorded - only that there is enough room left.
Then when you want to save something permanently, you can transfer from the harddrive to a recordable or re-writeable DVD. You may want to edit out the start and end of timer recordings (and any commercial breaks within the recording) before transferring to DVD.
You can record directly to DVD, in a similar manner to how you recorded directly to tape on your VHS recorder, but that is not the most practical way to use your harddisk/DVD recorder.
If you record or transfer something to a re-writeable DVD, the recorder will find the room it needs on the disc (usually after the last thing you recorded on that disc); if there isn’t enough room left on the DVD, you can either delete unwanted stuff or (re-)format the re-writable DVD before recording.
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