Deliver radio for nothing (3,4)
I believe the answer is:
set free
'deliver' is the definition.
(I've seen this before)
'radio for nothing' is the wordplay.
'radio' becomes 'set' (I've seen this in other clues).
'for nothing' becomes 'free' (I've seen this before).
'set'+'free'='SET FREE'
(Other definitions for set free that I've seen before include "Liberate" , "Release, remove restraints" , "Deliver - release" , "without the box" , "Uncaged birds have been" .)