Cmrr (Common Mode Rejection Ratio) Adjustment; Input/Output Gain Adjustment For Customer Setting - Sony BKPF-L753A Maintenance Manual

2-4. CMRR (Common Mode Rejection
Ratio) Adjustment
Measuring equipment: Audio level meter
1. Set the output of the generator to +15.0 dBm, 60 Hz.
CH2 adjustment
2. Connect the audio signal generator to the input of CH2
connector.
3. Connect the audio level meter to one output of CH2
connector.
4. Adjust the CH2 output level on the audio level meter.
Adjustment point: 1RV2/ADA-55 (C-2)
Less than _65 dBm (at 600 Z load)
Specification:
CH1 adjustment
5. Connect the audio signal generator to the input of CH1
connector.
6. Connect the audio level meter to one output of CH1
connector.
7. Adjust the CH1 output level on the audio level meter.
Adjustment point: 1RV1/ADA-55 (C-1)
Less than _65 dBm (at 600 Z load)
Specification:
BKPF-L753A

2-4. CMRR (Common Mode Rejection Ratio) Adjustment

2-5. Input/Output Gain Adjustment for Customer Setting

2-5. Input/Output Gain Adjustment for
Customer Setting
n
When the audio gain (COR1 or COR2) is not 0 dB, be sure
to perform this adjustment.
Measuring equipment: Audio level meter
1. Reset the shorting plugs (COR1 and COR2) on the
ADA-55 board to customer settings.
CH1 adjustment
2. Set the output of the generator to the customer setting
of COR1 as follows:
COR1/COR2 customer setting
_8 dB
_4 dB
(0 dB)
+4 dB
+8 dB
3. Connect the audio signal generator to the input of CH1
connector.
4. Connect the audio level meter to one output of CH1
connector.
5. Adjust the CH1 output level on the audio level meter.
Adjustment point: 1RV4/ADA-55 (A-2)
4.0 0.1 dBm (at 600 Z load)
Specification:
CH2 adjustment
6. Set the output of the generator to the customer setting
of COR2. (Refer to table in step 2.)
7. Connect the audio signal generator to the input of CH2
connector.
8. Connect the audio level meter to one output of CH2
connector.
9. Adjust the CH2 output level on the audio level meter.
Adjustment point: 1RV3/ADA-55 (A-3)
4.0 0.1 dBm (at 600 Z load)
Specification:
10. After turning off the power, reset the shorting plug
(COR3) and switches (S1 and S2) on the ADA-55
board to the customer settings.
Output signal
+12.0 dBm, 1 kHz
+8.0 dBm, 1 kHz
(+4.0 dBm, 1 kHz)
0.0 dBm, 1 kHz
_4.0 dBm, 1 kHz
(0 dBm = 0.775 Vrms)
2-3 (E)