3-4 (E)
HDCU-900 MM
3-2. Audio System Adjustment
3-2-1. Microphone Level Adjustment
Measures : Oscilloscope, Audio oscillator
Note
This adjustment is described on the premise that the output
impedance of the audio oscillator is 600
Z
.
Preparation
.
Board extension : AT-141 board (front side)
.
Board extension : AU-271 board (CAMERA side)
.
S126 (MIC CH-1 LEVEL)/AT-141 board panel side
→
MIN
.
S128 (MIC CH-2 LEVEL)/AT-141 board panel side
→
MIN
.
S402 (E-3)/AT-141
→
0 dBu
.
S401 (D-3)/AT-141
→
0 dBu
Adjustment Procedure
1.
MIC1 level adjustment
Input a sine wave of 1 kHz, 220 mV p-p (
_
20 dBu)
from the audio oscillator to 20-pin (X), 19-pin (Y) and
18-pin (G) of the extension board (camera side).
2.
Measuring point : TP401 (E-3)/AT-141 or AUDIO
OUTPUT CH-1 connector/HDCU
rear panel
Adjusting point :
1
RV401 (E-2)/AT-141
Specifications :
A = 1100
±
50 mV p-p
3.
Remove the cable that is connected in step 1.
4.
MIC2 level adjustment
Input a sine wave of 1 kHz, 220 mV p-p (
_
20 dBu)
from the audio oscillator to 15-pin (X), 16-pin (Y) and
17-pin (G) of the extension board (camera side).
5.
Measuring point : TP402 (D-3)/AT-141 or AUDIO
OUTPUT CH-2 connector/HDCU
rear panel
Adjusting point :
1
RV402 (D-2)/AT-141
Specifications :
B = 1100
±
50 mV p-p
Setting after Adjustment
S401 (D-3), S402 (E-3)/AT-141
→
Return to the original
setting.
600
Z
Audio oscillator
GND
GND
Y
X
A
600
Z
Audio oscillator
GND
GND
Y
X
B
3-2. Audio System Adjustment