A poignant broadcast about a South American (10)
I believe the answer is:
patagonian
'south american' is the definition.
(I've seen this before)
'a poignant broadcast about a' is the wordplay.
'broadcast' is an anagram indicator (letters scattered or cast around).
'about' indicates putting letters inside.
'a'+'poignant'='apoignant'
'apoignant' anagrammed gives 'patagonin'.
'patagonin' going around 'a' is 'PATAGONIAN'.
(Other definitions for patagonian that I've seen before include "South American" , "From southern Argentina and Chile" .)