Jog one's memory — as would campanologist? (4,1,4)
I believe the answer is:
ring a bell
This clue is a double definition.
'jog one's memory' is the first definition.
(I've seen this before)
'as would campanologist?' is the second definition.
(campanologist means a bell ringer)
(Other definitions for ring a bell that I've seen before include "Recall" , "Formally declare (appointment)" , "What door-to-door salesman's wont to do" , "as may 1A [SHEEPISH] part of 27 [WETHER-BY]" , "Contribute to ding-dong" .)