100 too old for area taken in by radio station (8)
I believe the answer is:
coverage
'area taken in by radio station' is the definition.
I can't tell whether this definition defines the answer.
'100 too old' is the wordplay.
'100' becomes 'C' (Roman numeral).
'too old' becomes 'overage' (I've seen this before).
'c'+'overage'='COVERAGE'
'for' is the link.
Can you help me to learn more?
(Other definitions for coverage that I've seen before include "Media reporting" , "Treatment (of an issue) by the media" , "Press reporting" , "news attention" , "Extent reached by advertising" .)