Small device for recording fiddle (4)
I believe the answer is:
scam
'recording fiddle' is the definition.
'scam' can be an answer for 'fiddle' (I've seen this in another clue). I'm unsure of the 'recording' bit.
'small device' is the wordplay.
'small' becomes 's' (abbreviation - e.g. clothes size).
'device' becomes 'cam' (cam is a kind of device).
's'+'cam'='SCAM'
'for' acts as a link.
Can you help me to learn more?
(Other definitions for scam that I've seen before include "Rip off" , "Racket" , "Fraudulent action" , "fiddle" , "Rip-off" .)