Test pulse regularly, for instance (7)
I believe the answer is:
example
'instance' is the definition.
(synonyms)
'test pulse regularly' is the wordplay.
'test' becomes 'exam' (synonyms).
'regularly' indicates alternate letters (regularly take one letter, leave next etc.).
The alternating letters of 'pulse' are 'ple'.
'exam'+'ple'='EXAMPLE'
'for' is the link.
(Other definitions for example that I've seen before include "Something to be imitated" , "warning" , "Fact that illustrates a general rule" , "Standard" , "Someone to emulate" .)