One's rung Robert, not yet eighteen (3,5)

I believe the answer is:

bob minor

'one's rung' is the definition.
(type of bell ringing sequence)

'robert not yet eighteen' is the wordplay.
'robert' becomes 'bob' (I've seen this before).
'not yet eighteen' becomes 'minor'.
'bob'+'minor'='BOB MINOR'

I've seen this clue in The Guardian.

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