Electronic Viewfinder System Adjustments; (Vf-102 Board); Power Supply Voltage Check; Horizontal And Vertical Position - Sony CCD-TRV32 Service Manual

18. Electronic viewfinder system adjustments

(VF-102 board)

Note : About 2200V dc is applied to CRT anode and about 200
Vdc to the grid. Be careful not to touch them. If hand
touches them, there is danger of electric shock
Preparation :
1. Disconnect a flexible board from CN901 on VF-102 board.
2. Connect equipments as follows.
regulated dc
power supply
+4.85Vdc
pattern
generator
Following signals
Required signals
1. Monoscope signal
Output amplitude:
Horizontal resolution:
Vertical resolution:
2. Dot pattern signal
Output amplitude
3. Contrast signal
Output amplitude
fH :
fV :
Others: Complies with NTSC and PAL. (Refer to Fig. 6-1-12.)
9µ S
Fig. 6-1-11
VF-102 BOARD (SIDE A)
1 5
CN901
Fig 6-1-12
CN901
1
2
3
4
5
1.0 Vp-p (75Ω terminated)
600 TV lines or more
350 TV lines or more
1.0 Vp-p (75Ω terminated)
0.5 Vp-p (75Ω terminated)
15.750kHz (NTSC)
15.625kHz (PAL)
60Hz (NTSC)
50Hz (PAL)
0.2V
0.3V
RV904
RV905

18-1. Power supply voltage check

Measuring Instrument
EVF5V
Measurement Point
Specification Value

18-2. Horizontal and vertical position

Purpose : Maintains horizontal position.
Adjustment error : Horizontal position cannot be maintained.
Signal
Adjustment
Specification Value
Adjustment procedure:
Order
1 Confirm that the horizontal and vertical picture sizes
satisfy the specification values.
4.5%

18-3. BRIGHT adjustment

Signal
Measurement Point
Adjustment
Specification Value
Adjustment procedure:
Order
1 Adjust RV904 until each step of gray scale signal is
clearly display. (For the brighter region, do not
increase brightness to such an extent that the cross-
hatch at the center of monoscope signal becomes
flared. For the dark region, do not decrease brightness
to such an extent that the first step (the darkest step)
and the third step cannot be identified.)
6-26
Digital voltmeter
CN901 Pin 1
4.65 + 0.1Vdc
Monoscope signal
RV905
Overscan 3.5 ± 3.5%
(horizontal) (one side)
Overscan 4.5 ± 5% (vertical) (one
side)
Procedure
3.5%
Monoscope signal
CRT screen
RV904
Each step of gray scale signal is
displayed clearly.
Procedure