Mic 1 Demodulation Adjustment; Mic 1 Level Adjustment - Sony CCU-TX7 Service Manual

4-7-6. MIC 1 Demodulation Adjustment

Note : Perform this adjustment only when replacing 1T201/
AA-90 board.
Equipment : Oscilloscope, Audio generator
To be extended : AA-90 board
Preparations :
1. AUDIO SELECT switch (CAMERA/CA-MIC/CA-LINE)/
CA-TX7/TX7P rear panel
2. Input the 1 kHz sine wave signal of the audio generator to
CH 1 of MIC IN (rear panel) on the CA-TX7/TX7P.
. Fig-2 (Refer to 4-1-5. Audio connection.)
3. Adjust the output level control of audio generator so that
the pin 19 (GND : pin 12)/AFM-15 board is 220 mV p-p.
Test point : TP8 (GND : E2)/AA-90 board
Adjustment Procedures :
1. Adjust the white core of 1T201/AA-90 board slowly so
that the DC level at TP8 (GND : E2) /AA-90 board is
1.24 ± 0.01 V dc.
2. Set the input range of oscilloscope to AC mode, and adjust
the blue core of 1T201/AA-90 board so that the sine wave
is minimum.
3. Repeat procedure 1.
4-30
→ "CA-LINE"
1.24 ± 0.01 V dc
GND
Minimum

4-7-7. MIC 1 Level Adjustment

Equipment : Oscilloscope, Audio generator
To be extended : AA-90 board
AFM-15 board (CA-TX7/TX7P)
Preparations :
1. AUDIO SELECT switch (CAMERA/CA-MIC/CA-LINE)/
CA-TX7/TX7P rear panel
2. Input the 1 kHz sine wave signal of the audio generator to
CH 1 of MIC IN (rear panel) on the CA-TX7/TX7P.
. Fig-2 (Refer to 4-1-5. Audio connection.)
3. Adjust the output level control of audio generator so that
the pin 19 (GND : pin 12) / AFM-15 board is 220 mV p-p.
4. S201 (0 dB/_20 dB)/AA-90 board → 0 dB
Test point : TP10 (GND : E2)/AA-90 board
Adjustment point : 1RV201 (MIC 1 LEVEL)/
AA-90 board
→ "CA-LINE"
1100 ± 50 mV p-p
CCU-TX7 (E)/V1