Sony HCD-ED2 Service Manual page 11

Record Bias Adjustment
Procedure :
1. Mode : Record
MD IN (JK301)
1) 315Hz
2) 10kHz
AF OSC
600 Ω
attenuator
2. Mode : Playback
recorded
position
set
MD OUT (JK301)
Confirm playback the signal recorded in step 1 become adjustment
level as follows.
If these levels do not adjustment level, adjustment the VR701 (L-
CH) and VR702 (R-CH) on the TAPE PREAMP board to repeat
steps 1 and 2.
Adjustment level : Playback output of 10kHz level diffrence
against 315Hz reference should be ±0.5 dB.
Adjustment Location : TAPE PREAMP board
Record Level Adjustment
Procedure :
1. Mode: Record
MD IN (JK301)
315Hz 50 mV (–23.8 dB)
AF OSC
600 Ω
attenuator
}
50 mV (–23.8 dB)
blank tape
CS-123
set
level meter
blank tape
CS-123
set
2. Mode: Playback
recorded
position
set
MD OUT (JK301)
Confirm playback the signal recorded in step 1 become adjustment
level as follows.
If these levels do not adjustment level, adjustment the VR705 (L-
CH) and VR706 (R-CH) on the TAPE PREAMP board to repeat
steps 1 and 2.
Adjustment level :
Playback level : 47.2 to 53.0 mV (–24.3 to –23.3 dB)
Adjustment Location : TAPE PREAMP board
Adjustment Location
[TAPE PREAMP BOARD] (Component Side)
VR706
REC BIAS
R
VR705
REC BIAS
level meter
VR703 VR704
PB LEVEL PB LEVEL
L R
L
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