Pioneer CDX-MG6056ZH, Руководство по обслуживанию

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CDX-MG6346ZH,MG6446ZH
7. GENERAL INFORMATION
7.1 DIAGNOSIS
7.1.1 TEST MODE
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CD Test Mode
1) Precautions on Adjustment
• The unit employs a single voltage (+5V) for the regu-
lator, thus the reference potential of the signal is
RFOUT (approximately 2.5V) rather than GND.
Inadvertent contact of REFOUT and GND during
adjustment can result not only in disabling normal
potential measurement but also in exposing the pick-
up to strong impacts due to malfunctioning of the
servo. Therefore, you are requested to observe the
following precautions.
• Make sure that the negative probe of the measuring
instrument is not connected to RFOUT or GND.
Special care must be exercised so that the channel 1
negative probe may not be connected to the oscillo-
scope and the channel 2 negative probe to GND.
Since the frame of the measuring instrument is usual-
ly at the same potential as the negative probe, the
frame of the measuring instrument must be changed
to floating status.
When RFOUT is inadvertently connected to GND, you
must immediately turn off the regulator or power
supply.
• The regulator must be turned off before mounting or
dismounting filters or wiring materials.
• You should not start adjustment or measurement
immediately after the regulator is turned on. It is rec-
ommended to run the player for approximately one
minute so that it may stabilize.
• When the test mode is turned on, various protective
functions from the software become unavailable.
Thus, you must make sure that undesirable electric or
mechanical shocks are not be given to the system.
• This model employs a photo-transistor for detecting
discs at their loading or ejection. Thus, if its outer
case is removed during repair work and internal parts
are exposed to light of strong intensity, malfunctions
including the following can result:
∗
The eject button becomes inoperable during play.
Pressing the eject button does not eject a disc and
play is continued.
∗
Loading becomes unavailable.
If a malfunction is recognized, appropriate remedial
actions must be taken. Such actions include chang-
ing the light source position, changing the unit posi-
tion and applying a cover to the photo-transistor.
• When you press the [EJECT] key to eject a disc, you
must not touch any other key until the ejection is
complete.
• If you press the [TRK+] or [TRK-] for the focus search
in the test mode, you must turn the power off imme-
diately. (Otherwise, the lens will be forced to stick to
the top or bottom, potentially resulting in the burning
of the actuator.)
2) Description of the Test Mode
Adjustment of this unit is done in parallel with the CD
control unit (DEH-M7126ZH or a head unit conforming
to the GA-NET BUS specifications), thus key opera-
tions for adjustments are done from the unit. Taking
the example of the DEH-M7126ZH, the following
describes how to turn on the test mode and operate
the keys. The keys referred to in the following are
those used on the DEH-M7126ZH.
• Turning on the Test Mode
Press the [4] and [6] keys simultaneously to turn on
the ACC and the backup.
• Ending the Test Mode
When ACC or Back up is off, the test mode is can-
celed.
• Operation of TR JUMPs (except 100TR) continues
after your finger has left the key. CRG MOVE and
100TR JUMP are forced to the tracking close mode as
soon as the key is released.
• Turning the power on or off resets the JUMP MODE
to the Single TR.