Broadcaster from east or west? (4)

I believe the answer is:

beeb

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'broadcaster' is the definition.
(I've seen this before)

I don't understand the rest of the clue.

(Other definitions for beeb that I've seen before include "Auntie (slang, palindrome)" , "UK broadcaster (informal)" , "BBC (colloq" , "BBC, familiarly" , "British Broadcasting Corporation (popularly)" .)

I've seen this clue in The Times.

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