Trackwork rider Damien Bradbury has been disqualified for 18 months over the discovery of an electrical apparatus during a trackwork session at a provincial racetrack.

Bradbury pleaded guilty to a charge of having a "jigger" in his possession while riding trackwork at Mornington on April 20.

His suspension is backdated April 22, the day he was stood down by stewards, and ends on October 22, 2016.

Stewards launched an investigation when the hand-held battery device was found at Mornington racecourse on April 20.