Audio Modulation Adjustment - Sony HDC1000 Maintenance Manual

3-9-2. Audio Modulation Adjustment

Preparation
1. Connect the oscilloscope to the spectrum analyzer as
shown below.
CH2 CH2
Probe
IN OUT
Oscilloscope
2. Set S1-4 on the TR-136 board to ON (HDC1550).
n
A 400 Hz sine wave is output from the test signal
generator in HDC1550.
Adjustment procedure
3. Adjust width A of each waveform while changing the
CENTER and SPAN of the spectrum analyzer.
Measuring equipment:
Spectrum analyzer
(via oscilloscope)
CENTER: 6.2 MHz (MIC 1)
SPAN:
RBW:
Test point: TP106 (GND: E200)/TR-136 board
Adjusting point and specification:
HDC1000/V1(E)
IN
Spectrum analyzer
6.7 MHz (MIC 2)
7.1 MHz (INCOM 1)
7.4 MHz (INCOM 2)
20 kHz (MIC 1, 2)
25 kHz (INCOM 1, 2)
1 kHz
A
1
2
3
Spectrum Adjusting
analyzer point/
CENTER/ TR-136 board
SPAN
1RV102
MIC 1 6.2 MHz/
20 kHz
MIC 2 6.7 MHz/ 1RV103
20 kHz
INCOM 1 7.1 MHz/ 1RV104
25 kHz
INCOM 2 7.4 MHz/ 1RV105
25 kHz
4. Re-set S1-4 on the TR-136 board to OFF.
B
E2
TP605
S1
RV761
TP604
RV601
RV602
TP801
RV801
TP401
RV721
TP721
E1
TP603
TR-136 BOARD (SIDE A)
Specification
A = 16.0 ± 0.2 kHz
A = 18.0 ± 0.2 kHz
A = 20.0 ± 0.2 kHz
A = 20.0 ± 0.2 kHz
Peak of portion B
Portion B
A
C
D
RV204
LV210
LV102
LV209
TP210
TP209
RV102
LV208
LV207
TP208
LV103
TP207
LV204
RV103
LV203
TP203
LV105
RV202
LV206
LV205
TP206
RV105
TP205
TP106
E200
LV202
TP202
TP201
LV104
E4
RV104
LV101
TP602
TP601
RV203
RV201
TP204
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