Section 3 Electrical Adjustment - Sony MDR-NC22 Service Manual

MDR-NC22
NOISE CANCEL VOLUME ADJUSTMENT
Connection:
AF oscillator
+
amplifier
–
Procedure:
1. Generate a sine wave of specific frequency (200 Hz) from a
AF oscillator, and output it from a speaker placed at the forward
position.
2. Wear this headphones on the ear, and turn on the [POWER]
switch.
3. With this headphones worn, adjust the RV1 (L-ch) and RV51
(R-ch) so that the volume from the speaker becomes lowest
aurally.
Note:
When the headphones are not covered with the ear pieces completely, the
adjustment may not be performed correctly.
Make sure that the ear pieces cover the headphone completely.
Adjustment Location:
– MAIN BOARD (Side A) –
RV51 (R-ch) RV1 (L-ch)
Noise Cancel
Volume Adjustment
6
SECTION 3
ELECTRICAL ADJUSTMENT
speaker
S101
POWER
OFF ON