Broadcast a tirade perhaps (7)
I believe the answer is:
radiate
'broadcast' is the definition.
(I've seen this before)
'a tirade perhaps' is the wordplay.
'perhaps' is an anagram indicator.
'a'+'tirade'='atirade'
'atirade' anagrammed gives 'RADIATE'.
(Other definitions for radiate that I've seen before include "A tirade (anag)" , "Emit rays; diverge" , "Travel from centre in all directions" , "Beam brightly, spread heat" , "Shine" .)