Terrible row about a fool losing head in station (5,3)
I believe the answer is:
radio two
'station' is the definition.
(BBC radio station)
'terrible row about a fool losing head' is the wordplay.
'terrible row' becomes 'rwo' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'about' means one lot of letters goes inside another.
'fool' becomes 'idiot' (I've seen this before).
'losing head' means to remove the first letter.
'idiot' with its initial letter taken off is 'diot'.
'a'+'diot'='adiot'
'rwo' going around 'adiot' is 'RADIO TWO'.
'in' acts as a link.
(Another definition for radio two that I've seen is " Broadcaster".)