Thank you Chelle - there are certainly a lot of them!
1(a) Radio chap is getting excited, having taken this?(11) (Third letter is h if high tea is correct
1(d) I rate a chairlift poorly but it'll keep you alive(10,5) (I was thinking it was maybe an anagram of I rate a chairlift and that it was life- something)
12(a) Denied referee cup tie now and then at Dartmouth(7)
5(d) What diabetic takes home after non-stop abuse(7)
6(d) More rejected what Henry established (6,2,7) (My head kept thinking along the lines of Catherine of Aragon although I know it is not the answer as the letters don't fit - I have no idea why it was coming into my head)
There are a few anyway - would be grateful of any help.