Sony DXF-20W, Service Manual

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2-2 (E)
DXF-20W
2-2. Viewfinder System Adjustment
2-2-1. Heater Voltage Pre-Adjustment
Note
When performing this adjustment, check “2-2-5. Bright
Calibration Adjustment”.
Preparation
.
Measuring equipment: Digital voltmeter (AC mode)
Adjustment procedure
Check the following voltage.
. Test point: TP3
↔
TP4/VF-88 board
. Specification: 0.635
±
0.015 V rms
If the above specification is not met, adjust
1
RV4 (VH-
ADJ)/VF-88 board so that the specification is met.
2-2-2. Focus Adjustment
Note
This adjustment and “2-2-3. Horizontal Frame Adjust-
ment”, “2-2-4. Heater Voltage Adjustment” and “2-2-5.
Bright Calibration Adjustment” affect with each other.
Therefore, repeat the adjustment until all specifications are
met.
Preparation
. Object: Resolution chart
. Measuring equipment: Waveform monitor
.
Lens
IRIS AUTO/MANU
→
MANU
. Viewfinder
BRIGHT control
→
Mechanical center
CONTRAST control
→
Fully clockwise
2
PEAKING control
→
Fully counterclockwise
3
Adjustment Procedure
1. Adjust the lens zoom so that the resolution chart
frame coincides with the underscanned picture frame
on the monitor screen.
2. Set the resolution on the monitor screen to the best
state with the lens focus.
Monitor screen
3. Adjust the lens iris so that the white level at VIDEO
OUT connector on the camera is as follows.
For NTSC: 100
±
2 IRE
For PAL: 700
±
14 mV
4. Adjust
1
RV3 (FOCUS)/VF-88 board so that the
picture on the viewfinder screen is best focused.
TP4
RV4
TP3
RV3
RV2
RV1
VF-88 board
VF-88 board