Screen Centering Check; Vertical Linearity Adjustment - Sony DXF-20W Service Manual

2-2-8. Screen Centering Check

Note
When performing the centering magnet adjustment in the
check of this section, perform "2-2-3. Horizontal Frame
Adjustment" and "2-2-7. Vertical Frame Adjustment".
Preparation
. Measuring equipment: Waveform monitor
. Viewfinder
→ Mechanical center
BRIGHT control
CONTRAST control → Mechanical center
→ Fully counterclockwise 3
PEAKING control
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.
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
700 ± 14 mV
For PAL:
4. Push the VF tube against the top chassis on the
horizontal position as shown in the illustration below.
Check that the image is in the center when it is viewed
through the viewfinder in the normal state.
If the image is not in the center, perform the centering
magnet adjustment to adjust the image to the center.
DXF-20W
VF tube
Top chassis
Centering magnet

2-2-9. Vertical Linearity Adjustment

Preparation
. Measuring equipment: Waveform monitor
. Viewfinder
→ Mechanical center
BRIGHT control
CONTRAST control → Mechanical center
→ Fully counterclockwise 3
PEAKING control
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.
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
700 ± 14 mV
For PAL:
4. Adjust 1RV105 (V-LIN)/DF-70 board so that each
circle at the four corners of resolution chart is the
perfect circle (symmetrical in top and bottom).
DF-70 board
2-9 (E)