Rec C Current Adjustment (Vc-195 Board) - Sony Handycam Vision CCD-TRV300E Service Manual

9. REC C Current Adjustment (VC-195 board)

Set the recording current levels of the REC Chroma signal. If it is
too low, chroma signal noise in played back picture will increased.
If too high, Y signal noises will increase and white modulation noises
will be produced.
Mode VTR recording (SP mode)
Signal No signal
Pin !º of CN910 (REC RF)
Measurement Point
Measuring Instrument Oscilloscope
Adjustment Page F
Adjustment Address 65
Specified Value A = 35.7±1.3mV
Connection:
1) Remove C085 (0.01µF, Pin !§ of IC202).
Note: After completing "REC L Level Adjustment" and "REC C
Current Adjustment", replace C085 with new parts (1-162-
970-11 CERAMIC CHIP 0.01µF 10% 25V).
2) Connect Pin 1 of IC001 and GND with a 0.01F capacitor.
0.01µF capacitor: 1-101-004-00
Preparations:
1) Select page: 0, address: 01, and set data: 01.
2) Select page: D, address: 14, after memorizing the data, set the
bit value of bit1 to "1". (Refer to "3. Bit value discrimination" of
"3-1-8. Service mode").
3) Select page: D, address: 15, after memorizing the data , set the
bit value of bit7 to "0".
4) Set to recording mode. (Use the wireless remote commander
of 8mm VCR, or connect Pin 6 of CN935 of DD-105 board
and GND with 4.7kΩ resistor for a second.)
4.7kΩ resistor: 1-249-425-11
Adjusting method:
1) Insert a tape, set to recording mode. (Refer to "Preparations".)
2) Select page: 0, address: 01, and set data: 01.
3) Select page: 3, address: 01, set data: 41, and press the PAUSE
button of the adjusting remote commander.
4) Select page: 2, address: 61, and set data: 30.
5) Select page: F, address: 65, change the data and set the REC
chroma signal level (A) to the specified value.
6) Press the PAUSE button of the adjusting remote commander.
7) Select page: 2, address: 61, and set data: 10.
8) Select page: 3, address: 01, set data: 00, and press the PAUSE
button of the adjusting remote commander.
9) Select page: 0, address: 01, and set data: 00.
Processing after completed adjustment:
1) Select page: 0, address: 01, and set data: 01.
2) Select page: D, address: 14, and set the data memorized at step
2) of "Preparations".
3) Press the PAUSE button of the adjusting remote commander.
4) Select page: D, address: 15, and set the data memorized at step
3) of "Preparations".
5) Press the PAUSE button of the adjusting remote commander.
6) Select page: 0, address: 01, and set data: 00.
5-48
Center of the luminance line width
1.35 µ sec
Fig. 5-3-14.
A