Sony RMT-V259M, Service Manual

Page: 91 / 117

6-5
2-6-1-2. Overall Audio Distorsion Factor Check
[Adjustment purpose]
Confirm that the audio distorsion is within the specification.
Mode Recording and playback (LP mode)
Signal 400Hz, –6.3dBs
Measurement Point LINE1 A(L) OUT (CN500
3
pin) or
LINE1 A(R) OUT (CN500
1
pin)
Measuring Instrument Distorsion meter
Specified Value Less than 1.0%
Note: Perform “Audio Output Level Check” before this adjustment.
Switch setting:
INPUT SELECT ................................... L1
[Check method]
1)
Input a 400Hz, –6.3dBs signal to both L and R channels of
LINE 1 (A(L/R)IN) terminal.
2) Record the signal in the LP mode.
3) Playback the recorded section.
4) Check that the 400Hz signal distorsion factor satisfies the
specified value.
2-6-1-3. Overall Noise Level Check
[Adjustment purpose]
Confirm that the noise level is within the specification.
Mode Recording and playback (SP mode)
Signal No signal :
Connect a shorting jumper between
A(L/R) IN (pins
2
and
6
) and Au
GND (pin
4
) of CN500
Measurement Point LINE1 A(L) OUT (CN500 3 pin) or
LINE1 A(R) OUT (CN500
1
pin)
Measuring Instrument Audio level meter
Specified Value Less than –67.5dBs
Switch setting:
INPUT SELECT ................................... L1
[Check method]
1)
Connect A(L/R) IN (pins
2
and
6
of CN500) and Au
GND (pin 4 of CN500) with a shorting jumper.
2) Record the signal in the SP mode.
3) Playback the recorded section.
4) Check that noise level is the specified value.
2-6-1-4. HiFi Audio Frequency Response Check
[Adjustment purpose]
Confirm that the frequency characteristics are within the
specification.
Mode Recording and playback
(SP/LP mode)
Signal
1
: 30Hz, –26.3dBs
2 : 400Hz, –26.3dBs
3 : 20kHz, –26.3dBs
Measurement Point LINE1 A(L) OUT (CN500
3
pin) or
LINE1 A(R) OUT (CN500
1
pin)
Measuring Instrument Audio level meter
Specified Value 0 ± 3dB
Note:
Perform “Audio Output Level Check” of “Hi-Fi Audio System
Check” before this adjustment.
Switch setting:
INPUT SELECT ................................... L1
[Check method]
1)
Input a 30Hz, –26.3dBs signal to both L and R channels of
LINE 1 (A(L/R)IN) terminal.
2) Record the signal in the SP/LP mode.
3) Input a 400Hz, –26.3dBs signal to both L and R channels of
LINE 1 (A(L/R)IN) terminal.
4) Record the signal in the SP/LP mode.
5) Input a 20kHz, –26.3dBs signal to both L and R channels of
LINE 1 (A(L/R)IN) terminal.
6) Record the signal in the SP/LP mode.
7) Playback the recorded section.
8) Press the AUDIO MONITOR button of the remote commander
and select the normal audio mode (STEREO indicator on the
display window turns off.).
9) Check that the 20kHz, 400Hz signal level against to the 30Hz
signal level satisfies the specified value.
2-6-1-5. Audio PB Level Check
[Adjustment purpose]
Confirm that the Audio PB Level are within the specification.
Mode Playback
Signal Alignment tape : SP mode
HiFi audio position
Measurement Point LINE1 A(L) OUT (CN500
3
pin) or
LINE1 A(R) OUT (CN500
1
pin)
Measuring Instrument Audio level meter
Specified Value –6.3 ± 2dBs
[Check method]
1)
Check that the audio PB level the specified value.