Bose Lifestyle CD5 Series I, Service Manual

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CD TERMS
Basic Terms
Access: See track access.
Access Time: The length of time required to change tracks.
CD Mechanism: The mechanical assembly of components used to read information off of the
CD. It contains the optical pickup, sled assembly, disc motor, sled motor, and spindle.
Disc Motor: The motor which spins the disc.
Focus Actuator: The magnet and coil assembly that moves the optical pickup’s lens up and
down.
Laser: A semiconductor light source similar to an LED that is used to read the data off of a CD.
When the laser is turned on it can be seen as a red glow inside the lens.
Laser Pickup: The portion of the CD mechanism that contains the laser diode, lens, focus and
tracking actuators, and photodetector diodes.
Mechanism: see CD Mechanism.
Optical Pickup: See Laser Pickup.
Playability: The extent to which a player can successfully play less than perfect discs. Play-
ability is measured with special test discs (playability discs) that contain certain types of de-
fects and problems.
Playability Disc: A disc which contains a calibrated defect or problem. These include eccen-
tricity, warp, scratch, void, black dot, and fingerprints.
Parking: When the sled is moved to the innermost position on the disc. This is done before (if
necessary) and after playing a disc.
Sled: The portion of the CD mechanism that moves inside to outside to position the optical
pickup near the desired track.
Sled Motor: The motor which moves the sled back and forth.
Spindle: The hub that the disc sits on.
Track Access: The process of moving from one track on a disc to a different track.
Tracking Actuator: The magnet and coil assembly that moves the optical pickup’s lens inside
and out.
Playability Terms
Dropout: A momentary loss of the audio signal, usually caused by a large scratch or other
optical defect.