Raven, 35, joins the club from Warrington Town, and has also featured at Liverpool, Carlisle United, Tranmere and Inverness.
Manager Neil Young said: "We have been looking for an experienced centre half since the start of pre-season to add to our fairly young squad.
"Dave has had a good career in both league and non-league and will bring his wealth of experience to us, almost completing our squad for the new season."
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