12-62. Which of the following is a description of the
operation of a drive that uses constant linear
velocity?
1. The speed of the disc decreases as the
read head moves toward the outer edge of
the disc
2. The speed of the disc increases as the read
head moves toward the outer edge of the
d i sc
3. The speed of the disc remains constant
throughout the range of the read head
4. The physical sizes of the sectors on the
spiral track increase toward the outer edge
of the disc
12-63. Sectors on a CD-ROM are accessed by
which of the following address forms?
1. Track, sector, head
2. Minute: second: sector
3. Hour: minute: sector
4. Cylinder: sector
12-64. When a CD-ROM disc is manufactured. the
data is written on the disc in which of the
following formats?
1. Eight-to-fourteen modulation
2. Modified frequency modulation
3. Run length limited 2,7
4. Non-return-to-zero
12-65. The laser used in the optical head of a CD-
ROM drive emits light in which of the
following bands?
1. Ultraviolet
2. Visible spectrum
3. Infrared
4. White
12-66. The collimating lens in a CD-ROM drive’s
optical head is used to perform which of the
following functions?
1. To focus the laser beam on the disc
2. To reduce the divergence of the laser
beam
3. To focus the laser beam on the
photodector circuit
4. To reduce the intensity of the laser beam
12-67. The final step in focusing the laser beam on
the disc is accomplished by which of the
following items?
1. Optical head
2. Objective lens
3. Collimating lens
4. Plastic coating on the disc
12-68. Splitting the reflected laser beam and
directing the split beams to a set of
photodiodes is used in which of the following
functions?
1. Ensuring the disc is rotating at the proper
speed
2. Maintaining proper tracking and focus
3. Detecting data on the disc
4. Both 2 and 3 above
12-69. The control section decodes the eight-to-
fourteen data read from a disc using what
method, if any?
1. Checking the data for parity errors
2. Using the data to address a ROM for the
proper byte
3. Adding the data to a set value to find the
proper byte
4. None; the data does not need to be
decoded
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