Learn by chance about this place on radio (8)
I believe the answer is:
overhear
'learn by chance' is the definition.
(hear about something accidentally)
'about this place on radio' is the wordplay.
'about' becomes 'over' (both can mean around).
'this place' becomes 'here' (I've seen this in another clue).
'on radio' indicates a 'sounds like' (homophone) clue.
'here' sounds like 'hear'.
'over'+'hear'='OVERHEAR'
(Other definitions for overhear that I've seen before include "Bug" , "Listen without the speaker's knowledge, maybe by accident" , "Listen accidentally without speaker's knowledge" , "Inadvertently catch" , "Listen accidentally unknown to speaker" .)