Pioneer AVH-X7700BT/XNEW5, Руководство по обслуживанию

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AVH-X7700BT/XNUC
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8. EACH SETTING AND ADJUSTMENT
8.1 DVD ADJUSTMENT
1) Precautions in adjustment
Employing the single voltages including 5 V and 3.3 V as the power supply, the machine has the reference potential
for signals being not the GND but VREF (approx. 2.2 V) and VHALF (approx. 1.65 V).
Confusion between the reference voltage and the GND for connection at the time of adjusting the product not only
prevents the proper measurement of potentials but results in the erroneous operation of the servo, giving a high
impact on the pickup. Therefore, be careful of the following:
Do not confuse the reference voltage and the GND at the negative side of the instrument probe. Particularly, do not
connect the negative side of ch1 of the oscilloscope to the reference voltage, or the negative side of the probe of
ch2 to the GND. Also, set the instrument to the floating status as the instrument often has the same potential as the
negative side of the probe.
If the reference voltage is connected to the GND by mistake, turn OFF the regulator or the power immediately.
• Make sure to remove various filters and wire rods necessary for measurement while the regulator is OFF.
• Before adjustment and measurement after turning ON the regulator, run the instrument for around a minute until
the circuit is stabilized.
• In the test mode, do not apply any mechanical or electric shock during adjustment as protections through software
do not operate in this mode.
• Once the EJECT key is pressed, do not press any other key until the disc is completely ejected.
• Power OFF immediately in case of run a way.
• Turning the volume for adjusting the laser power of the pickup unit may result in the breakage of the laser diode.