4-3 CD
4-3-2 To Adjust Tracking Gain (PLAY mode)
1. 2. 3. Connect the GND terminal of the oscilloscope to Vref and (+) terminal to TP2. Load and play the disc While the disc is running adjust the gain with NVR1704 as shown below. Normal frequency Low frequency High frequency
---0 V
---0 V
---0 V
TE CENTER FE CENTER E.F BAL F.BIAS
NVR1704 NVR1703 NVR1702
NVR1701
VOLT/DIV : 0.2V TIME/DIV : 2mS
VOLT/DIV : 0.2V TIME/DIV : 2mS
VOLT/DIV : 0.2V TIME/DIV : 2mS
Vref
4-3-3 To Adjust Focus Gain (PLAY mode)
1. 2. 3. Connect the GND terminal of the oscilloscope to Vref and (+) terminal to TP1. Load and play the disc While the disc is running adjust the gain with NVR1703 as shown in the following figure. Normal frequency
TP1
---250mV
Low frequency
High frequency
TP2
---100mV ---0 V ---0 V
---100mV ---0V
VOLT/DIV : 0.1V TIME/DIV : 2mS
VOLT/DIV : 0.1V TIME/DIV : 2mS
VOLT/DIV : 0.1V TIME/DIV : 2mS
4-3-4 To Adjust E/F Balance (PLAY mode)
1. 2. 3. Set TIME/DIV of the oscilloscope to 2mS. Set Volt/DIV of the oscilloscope to 0.5V. Ground the scope input and set to DC and then set the DC range. Connect the GND terminal of the oscilloscope to Vref and (+) terminal to center to TP2. Load and play the disc. Turn NVR1704 counterclockwise to the minimum value. Raise NVR1702 and adjust the waveform so that its middle comes to GND of the oscilloscope (or until the upper half of waveform becomes symmetrical to the bottom half, A=B) Adjust NVR1704 (arrow) for normal sound.
4-3-1 To Adjust FOCUS BIAS(STOP mode)
1. 2. 3. 4. Set Volt/Div of the oscilloscope to DC 100mV. Ground the scope input and set the waveform to 0V, DC range. Connect the GND terminal of the oscilloscope to Vref, and (+) terminal to center of TP1. Set NVR1701 to 0mV.
