Ir Audio Deviation Adjustment (Mi-37 Board) - Sony DCR-TRV820 Service Manual

3. IR Audio Deviation Adjustment (MI-37 board)

Mode VTR stop
Audio signal:
400 Hz, –7.5 dBs: Audio left and
right terminal of A/V jack
Signal
Video signal:
Color bar signal: VIDEO terminal
of A/V jack
AUDIO L terminal and AUDIO R
Measurement Point terminal of IR receiver jig
(Terminated at 47 kΩ)
Measuring Instrument Audio level meter
Adjustment Page F
Adjustment Address 7F
Signal level: –7.5 ± 1.0 dBs Level
Specified Value
difference of L and R: Below 2 dB
Connection of Equipment
Connect the measuring device as shown in the following figure,
and adjust.
Pattern generator
VIDEO OUT
(75 Ω)
Audio oscillator
Attenuator
Video
Audio (L)
600 Ω
Audio (R)
600 Ω (270 Ω (1-249-410-11) + 330 Ω (1-249-411-11))
Adjusting method:
1) Select page: 0, address: 01, and set data: 01.
2) Connect the audio level meter to the AUDIO L terminal of the
IR receiver jig.
3) Select page: F, address: 7F, change the data and set the 400 Hz
audio signal level to the specified value.
4) Press the PAUSE button.
5) Connect the audio level meter to the AUDIO R terminal of the
IR receiver jig.
6) Check that the 400 Hz audio signal level is within the speci-
fied value. If outside, repeat from step 3).
7) Select page: 0, address: 01, and set data: 00.
Main unit
A/V jack
Fig. 5-3-17
5-52
IR receiver jig
AUDIO OUT
L R
Audio level meter
47 kΩ
47 kΩ (1-249-437-11)