DEH-1400,14
6. ADJUSTMENT
6.1 CD ADJUSTMENT
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 VREF(approx. 2.1V) instead of GND.
If VREF 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 After pressing the EJECT key, do not press any other
equipment to VREF and GND together. It is especiallykey until the disk is completely ejected.
important not to connect the channel 1 negative
probe of the oscilloscope to VREF with the channel 2Y If the ] or [ key is pressed while focus search is in
negative probe connected to GND.progress, immediately turn the power off (otherwise
Since the frame of the measuring instrument is usual-the actuator may be damaged due to adhesion of the
ly at the same potential as the negative probe, changelenses).
the frame of the measuring instrument to floating sta-
tus.
If by accident VREF comes in contact with GND,
immediately switch the regulator or power OFF.
Y Always make sure the regulator is OFF when connect-
ing and disconnecting the various filters and wiring
required for measurements.
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.
Y Since the protective systems in the unit's software are
rendered inoperative in test mode, be very careful to
avoid mechanical and /or electrical shocks to the sys-
tem when making adjustment.
Y The RFI and RFO signals are easy to oscillate because
of a wide band. When observing them, insert a resis-
tor of about 1 k& to the series.
Y This equipment will not guarantee the load ejection
operation when the mechanical unit is turned upside
down. In particular, if the ejection operation is incor-
rectly performed and recovery is disabled, the recov-
ery is enabled by resetting a product or turning ACC
off to on.
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ACEC
