Sony GV-D300 Operating Instructions (primary manual), Service Manual

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3-7. AUDIO SYSTEM ADJUSTMENTS
• Perform the adjustment using the color bar signal as a video signal
input for the VIDEO jack.
[Connection of Audio System Measuring Devices]
Connect the audio system measuring devices as shown in Fig. 5-3-24.
Fig. 5-3-24.
1. Playback Level Check
Mode Playback
Signal Alignment tape:
For audio operation check
(XH5-3 (NTSC))
(XH5-3P (PAL))
Measurement Point AUDIO jack left or right
Measuring Instrument Audio level meter and frequency
counter
Specified Value 32 kHz mode: 1 kHz, +3.0 ± 2.0dBs
48 kHz mode: 1 kHz, +3.0 ± 2.0dBs
44.1 kHz mode EMP OFF section:
7.35kHz +2.0 ± 2.0dBs.
44.1 kHz mode EMP ON section:
–6 ± 2 dB from the signal level
during EMP OFF.
Checking Method
1)
Check that the playback signal level is the specified value.
2. Overall Level Characteristics Check
Mode Recording and playback
Signal 400Hz, –7.5dBs signal: AUDIO jack
left and right
Measurement Point AUDIO jack left or right
Measuring Instrument Audio level meter
Specified Value –7.5 ± 3.0dBs
Checking Method
1)
Input the 400Hz, -7.5dBs signal in the AUDIO jack left and
right.
2) Record the signal.
3) Playback the recorded section.
4) Check that the 400Hz signal level is the specified value.
3. Overall Separation Check
Mode Recording and playback
Signal 400Hz, –7.5dBs signal: AUDIO jack
<right> [left]
(Insert a shorting plug to AUDIO jack
<left> [right])
Measurement Point AUDIO jack <left> [right]
Measuring Instrument Audio level meter
Specified Value Below –40dBs
(IHF-A filter ON)
< >: Left channel check
[ ] : Right channel check
Checking Method
1)
Input the 400Hz, –7.5dBs signal in the AUDIO jack <right>
[left] only. (Insert a shorting plug to AUDIO jack <left> [right])
2) Record the signal.
3) Playback the recorded section.
4) Check that the signal level of the AUDIO jack <left> [right] is
the specified value.
VIDEO
L R
AUDIO
VIDEO OUT
(75
Ω
)
Pattern generator
Main unit
Audio generator
Attenuator
600
Ω
600
Ω
: 270
Ω
(1-249-410-11) + 330
Ω
(1-249-411-11)
L R
AUDIO
VIDEO
Main unit
Monitor TV
47k
Ω
47k
Ω
47k
Ω
(1-249-437-11)
Audio level meter
or distortion meter
Recording
Playback