Picture AM radio broadcast (7)
I believe the answer is:
diorama
'picture' is the definition.
(I know that diorama is a type of picture)
'am radio broadcast' is the wordplay.
'broadcast' indicates anagramming the letters (letters scattered or cast around).
'am'+'radio'='amradio'
'amradio' anagrammed gives 'DIORAMA'.
(Other definitions for diorama that I've seen before include "Representation of scene" , "AM radio? (anag)" , "contrived scene" , "Model representing a scene with three-dimensional figures" , "Miniature three- dimensional scene" .)