- Jog dial
A jog dial, jog wheel, shuttle dial, or shuttle wheel is a type of knob, ring, wheel, or dial which allows the user to shuttle or jog through
audio orvideo media. It is commonly found on models ofCD player s which are made fordisc jockey s, and on professional video equipment such asvideo tape recorder s. More recently, they are found onhandheld PDAs, and as thescroll wheel oncomputer mice . "Jog" refers to going at a very slow speed, whereas "shuttle" refers to a very fast speed.There are two basic types of wheels. One type has no stops and can be spun the entire way around, because it is a relative
rotary encoder . This type depends on tracking the actual motion of the dial: the faster it spins forward or back, the faster it fast-forwards orrewind s. Once the dial stops moving, the media continues playing or remains paused at that point. Another type has stops on either side, and often has three or so speeds which depend on how far it is turned. Once the wheel is released, it springs back to the middle position and the media pauses or begins playing again.If the device is set or designed to pause after the wheel is used, the audio is often
stutter ed, repeating a small section over and over again. This is usually done on DJ CD players, for the purpose ofbeatmatching , and is equivalent to an earlierturntablist DJ moving aphonograph record back and forth slightly to find the physical location of a starting beat within the groove. On video, the pause is afreeze frame of the currentvideo frame .Sony Corporation is known to hold a patent for 5-way version of jog dial, a device allowing up and down scrolling, right and left deflections and a pressure. Such jog dial was a feature of SonyCLIÉ PDA series andSonyEricsson P800 ,P900 andP910 smartphones. 5-way jog dial is not used by Sony or its subordinaries since 2006.
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