The Irish under 21 cap is currently on the books of Russell Slade's former club Scarborough but is keen to return to league football after starting out with Sunderland.
Capper is capable of playing anywhere in defence and on the wing. With Slade's prefered wingback system, Capper could well prove a useful signing as extra cover for John McDermott and Jason Crowe.
Capper has already had a trial with Sheffield Wednesday this season but will now try his look with Town, starting with the reserves game against Lincoln.