connecting recorder to in built hd tuner

I bought a samsung recorder ( http://www.samsung.com/au/consumer/...yer&subtype=dvdrecorder&model_cd=DVD-R155/XSA ) and i want to record tv shows in hd but i cant connect it to my tv which has a built in hd tuner( http://www.samsung.com/au/consumer/...evision&subtype=lcdtv&model_cd=LA40R81BDX/XSA ).i can use the dvd but i just cant find the channels on it . I have searched the net and couldnt find anything.

Thanks.

edit: im using a hdmi cable