CDX-P2050VC,P2050VN,P2050VS
7. GENERAL INFORMATION
7.1 DIAGNOSIS
7.1.1 TEST MODE
- CD Test Mode
1) Precautions2) Test Mode
Y This unit uses a single power supply (+5V) for the reg-This mode is used for adjusting the CD mechanism
ulator. The signal reference potential, therefore, ismodule of the device.
connected to REFO(approx. 2.5V) instead of GND.
If REFO and GND are connected to each other by mis-Y Test mode starting procedure
take during adjustments, not only will it be impossi-Reset while pressing the 4 and 6 keys together.
ble to measure the potential correctly, but the servo
will malfunction and a severe shock will be applied toY Test mode cancellation
the pick-up. To avoid this, take special note of the fol-Switch ACC, back-up OFF.
lowing.
Do not connect the negative probe of the measuringY If the 8 or 9 key is pressed while focus search is in
equipment to REFO and GND together. It is especiallyprogress, immediately turn the power off (otherwise
important not to connect the channel 1 negativethe actuator may be damaged due to the lens stuck).
probe of the oscilloscope to REFO with the channel 2
negative probe connected to GND.Y Jump operation of TRs other than 100TR continues
Since the frame of the measuring instrument is usual-after releasing the key. CRG move and 100TR jump
ly at the same potential as the negative probe, changeoperations are brought into the OTracking close� sta-
the frame of the measuring instrument to floating sta-tus when the key is released.
tus.
If by accident REFO comes in contact with GND,Y Powering Off/On resets the jump mode to OSingle TR
immediately switch the regulator or power OFF.(91)�, the RF AMP gain setting to 0 dB, and the auto-
matic adjustment value to the initial value.
Y Always make sure the regulator is OFF when connect-
ing and disconnecting the various filters and wiringY During exchanging discs, do not press the keys for
required for measurements.the discs to be exchanged.
Y Before proceeding to further adjustments and mea-
surements after switching regulator ON, let the player
run for about one minute to allow the circuits to stabi-
lize.Key to adjustment textHEAD UNIT (6 keys type)
Y Since the protective systems in the unit's software areinside (12 keys type)
rendered inoperative in test mode, be very careful toBANDBAND
avoid mechanical and /or electrical shocks to the sys-TRK+/FFTRK+/FF
tem when making adjustment.
TRK-/REVTRK-/REV
Y Disc detection during tray extraction and return oper-71
ations is performed by means of the photo transistor82
in this unit. Consequently, if the inside of the unit is93
exposed to a strong light source with the outer casing104
removed for repairs or adjustment, the following mal-115
functions may occur:
*Even with a disc loaded, the unit detects "no disc"126
and cannot start play.DISC-DISC-
*Although a 12-cm disc is loaded, the unit detectsSOURCE ON/OFFSOURCE ON/OFF
"8cm disc" mistakenly.
When the unit malfunctions this way, either re-posi-
tion the light source, move the unit or cover the photo
transistor.
Y During exchanging discs, do not press the keys for
the discs to be exchanged.
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ACEC
