NAD 512 - Important Notes; Optical System Pick-Up Handling; Laser Beam Emission Safety

IMPORTANT NOTES
INSTRUCTION FOR HANDLING OPTICAL SYSTEM BLOCK PICK-UP
Electrostatic
breakdown
of
the
laser
diode
in
the
optical
system
block
may
occur
due
to
a
potential
difference
caused
by
electrostatic
charge
accumulated
on
clothing,
human
body,
etc.
A
ground
must
be
provided
as
follows
to
prevent
any
electrostatic
charge
during
unpacking
or
repair
work.
1. Ground for Human Body
Be
sure
to
wear
a
ground
band
(1M
ohm)
that
is
properly
grounded
to
remove
any
static
electricity
that may be charged on the body.
2. Ground for Work Bench
Be
sure
to
place
a
conductive
sheet
(1M
ohm)
or
copper
plate
with
proper
grounding
on
the
work
bench or other surface on which the pick-up is to be placed.
3.
Because
the
static
electricity
charge
on
the
clothing
does
not
discharge
through
the
body
grounding
band,
do not
let
clothing
to get
in
contact
with
the pick-up
unit.
INCORRECT ; CORRECT
1. Grounding band
By
EN
won
&
NOTE: Laser diodes are so susceptible to damage
from static electricity that even if a static discharge
does not ruin the diode, it can shorten its life or cause
it to work improperly.
1M ohm
2. Conductive Sheet
or Copper Plate
PRECAUTIONS FOR CHECKING BEAM EMISSION
The
laser
beam
of
this
unit
is
focused
on
the
reflecting
surface
of
the
objective
lens
in
the
optical
system
block.
Therefore,
keep
your
eyes
at
least
12
inches
(30
cm)
away
from
the
objective
lens
when
the
laser
diode
is
ON.
(Operation
Check
Method
for
Laser
Diode
and
Focus
Search
Function.)
When
the
POWER
switch
is
turned
ON
after
the
chucking
plate
is
removed,
observe
the
objective
lens
and
confirm
that
the
following
operations
are
performed
properly.
(The
optical
system
block
should
be
at
the
lead-in
area
position
when
it
is
checked
at
this
time.)
(1)
The
laser
should
be
at
the
innermost
position
after
the
checking
place
is
removed.
(2)
The
diffused
light
of
the
laser
beam
can
be
seen
when
the
POWER
switch
is
turned
ON.
(3)
Vertical
(up
and
down)
movement
of
the
objective
lens
(2
or
3
times)
will
take
place.
13
PRECAUTIONS WHEN CHANGING LASER PICK-UP
When
removing
the
pick-up
assembly,
short
circuit
the
PCB
tracks
on
the
optical
block
as
shown
in
the
drawing
in order
to
protect
the pick-up
before
removal.
NOTE:
Replacement
pickup
assemblies
are
supplied
with
the
PCB
pattern
already
protected.
DO
NOT
REMOVE
THE
SHORT
CIRCUITS
UNTIL
YOU
HAVE
FINISHED
FITTING
THE
PICK-
UP:
Caution:
Laser diodes are extremely susceptible to damage from static eletricity. Even if a static discharge
does not ruin the diode, it can shorten its life or cause it to work improperly. When replacing the
pick-up, use a conductive mat, a grounded soldering iron, and so on, to protect the laser diode
from static damage.
Ground Conductive
Wrist Band for Body
Soldering
lron with
Ground
Ground
Line
wire
Less
than
10
ohm
Conductive Gum Mat
14