Audio System Adjustments; Playback Level Check; Overall Level Characteristics Check; Overall Separation Check - Sony GV-D300 Service Manual

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.
Recording
Pattern generator
VIDEO OUT
(75 Ω )
600 Ω
Audio generator
Attenuator
600 Ω : 270 Ω (1-249-410-11) + 330 Ω (1-249-411-11)
Playback
Main unit
AUDIO
VIDEO L R
Monitor TV
Fig. 5-3-24.
Main unit
AUDIO
L
R
VIDEO
47k Ω (1-249-437-11)
47k Ω
47k Ω
Audio level meter
or distortion meter

1. Playback Level Check

Mode
Signal
Measurement Point
Measuring Instrument
Specified Value
Checking Method
1) Check that the playback signal level is the specified value.

2. Overall Level Characteristics Check

Mode
Signal
Measurement Point
Measuring Instrument
Specified Value
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
Signal
Measurement Point
Measuring Instrument
Specified Value
< >: 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.
5-31
Playback
Alignment tape:
For audio operation check
(XH5-3 (NTSC))
(XH5-3P (PAL))
AUDIO jack left or right
Audio level meter and frequency
counter
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.
Recording and playback
400Hz, –7.5dBs signal: AUDIO jack
left and right
AUDIO jack left or right
Audio level meter
–7.5 ± 3.0dBs
Recording and playback
400Hz, –7.5dBs signal: AUDIO jack
<right> [left]
(Insert a shorting plug to AUDIO jack
<left> [right])
AUDIO jack <left> [right]
Audio level meter
Below –40dBs
(IHF-A filter ON)