Preparation Of Adjustment; Input/Output Gain Adjustment - Sony BKPF-L753A Maintenance Manual

2-2. Preparation of Adjustment

2-3. Input/Output Gain Adjustment

2-2. Preparation of Adjustment
1. Extend the ADA-55 board with a extension board.
2. Write the customer settings of the shorting plugs
(COR1, COR2, and COR3) and switches (S1, and S2)
on the ADA-55 board down in following table.
3. Set their shorting plugs and switches as follows:
Ref. No. (Address) Setting at adj.
COR1 (A-3) 0 dB
COR2 (A-1) 0 dB
COR3 (C-2) ST (STEREO)
S1 (D-1) ON (600 Z)
S2 (D-2) ON (600 Z)
4. Turn on the power of equipment (the signal generator,
audio level meter, and interface unit PFV-L1 or
PFV-L10), and warm up them for about ten minutes.
5. Attach the 600 Z resister for termination to the audio
level meter.
COR2
RV4
D1
COR3
COR1
RV3
ADA-55 Board (Side A)
2-2 (E)
Customer setting
S1
1
RV1
1
S2
RV2
MO
ST
2-3. Input/Output Gain Adjustment
Measuring equipment: Audio level meter
1. Set the output of the generator to +4.0 dBm, 1 kHz.
(0 dBm = 0.775 Vrms)
CH1 adjustment
2. Connect the audio signal generator to the input of CH1
connector.
3. Connect the audio level meter to one output of CH1
connector.
4. Check that COR2 (A-1) is set to 0 dB.
If not, set it to 0 dB.
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. Connect the audio signal generator to the input of CH2
connector.
7. Connect the audio level meter to one output of CH2
connector.
8. Check that COR1 (A-3) is set to 0 dB.
If not, set it to 0 dB.
9. Adjust the CH2 output level on the audio level meter.
Adjustment point: 1RV3/ADA-55 (A-3)
Specification: 4.0 0.1 dBm (at 600 Z load)
BKPF-L753A