I am newbie in the area of clutches. I am making a motorized cable reel (DC motor) which I needed to make it easy for anyone to pull the cable reel out manually without much effort. Only pulling the cable out is manual. The retraction of the cord is done automatically via the DC motor. So, based on my research online, one way bearings mounted on my dc motor sprocket (http://www.skf.com/group/industry-solutions/two-three-wheelers/applications/engine/start-system/skf-one-way-clutch/index.html [Broken]) seem to be the way to easily/freely pull the cord reel out manually without too much effort. But based on my understanding of this one way bearing, I would need disengage this one way bearing clutch while I need to retract the cord back in the opposite direction. If this statement is correct, I was wondering how I should disengage this clutch for retracting the cable back in. Do I have to use a powered electromagnetic clutch (something like this,http://ogura-clutch.com/electromagnetic_clutch.php ) which will get engaged/disengaged while powered , and thus allow the cord to get retracted back in easily ? Is this the only way of doing this ?