After reading the manual for it, I found that you can - bit it looks like a standard line-in socket, as you'd use the red & white sockets on the front AV. Normal turntables have a low sound output which means you'll need a pre-amp or you'll need to connect it through the amplifier on your stereo. The turntable plugs into the phono input on the amplifier as normal and then the record-out for the tape deck plugs into the DVD recorder (this is how my Kenwood one is plugged in anyway). Some modern turntables also have a built-in pre-amp which means you can connect the turntable straight to the recorder. Once it's connected the process for recording an audio CD is as follows (taken from the manual):
Audio CD Recording
1. Place a well-prepared CD-R / CD-RW disc onto the
tray with the disc’s label face up.
2. Press [ GUIDER ] to display the Easy Guider
menu, press   to select “Record” and then
3. Press   to select the audio signal input (TV,
Front AV, SCART, DV) and press [ENTER].
4. Press   to select “Audio CD” as the desired
recording format and then press [ENTER].
5. Press   to select the desired TV Sound and
then press [ENTER].
6. “Go!” is selected. Press [ENTER] to record your
audio signal into a recordable CD disc.
7. Press [EDIT] to create an new audio track into disc
8. Press [ STOP] to stop audio recording.
1.Single press of [EDIT] key will automatically create an new audio
track by 2 sec interval.
2.Audio source input during these 2 sec will be recorded onto the
beginning of the next track.
3.You must finalize the disc before you can playback the disc on
other Audio CD / DVD / VCD / SVCD player or CD / DVD-ROM
on a PC.