3. Observe the viewing screen and adjust RP1 to center the text on the raster.
White Balance/Gray Scale Tracking
The CRT Drive Controls (RP1 on the CRT Drive Panels) and Screen or G2 Controls (on the
G2/Focus Assembly between the red and green lenses) are adjusted using the following steps.
1. Set the Picture, Sharpness, and Brightness controls at midrange.
2. Turn the Color fully down.
3. Set all CRT Drive Controls to maximum (CW) and the Screens to minimum (CCW).
4. Tune the set to a snowy channel.
5. Move Service Plug J216 on the Deflection Panel to the service Set-Up position.
6. Adjust each G2 control to obtain a faint line(which appears white with all three colors).
7. Return the Service Plug to the normal position.
8. Check gray scale tracking. Adjust the Brightness control from maximum to
minimum, watching for possible color shift.
9. Re-adjust the CRT Drive controls for best high to low light gray scale.
Video Processor Panel Controls
1. Set all customer controls to midrange.
2. Insert a bar pattern from an NTSC generator.
3. Set RP5 (Peak contrast) to full CCW.
4. Adjust RP4 (Subbrightness) until the last line is black.
5. Adjust RP2 (Black level) until the first bar is white.
6. Adjust RP3 (Subpicture) for a sharp, uniform division between bars.
7. View a picture with bright white highlights. Check for blooming in the white areas
r
or raster edge. Readjust RP2 and/or RP4 until blooming disappears.
NOTE: If a bar pattern generator is not available, the adjustments may be made on a high white
level picture. Begin with RP2 and RP4 set fully CCW. RP5 should always be set fully CCW.
Set RP3 to 75% rotation towards CCW. Begin rotating RP2 CW until minimum blooming is the
white areas is observed. If the overall picture brightness is below proper viewing level before
this occurs, turn RP4 CW slightly and begin procedure again with RP2 full CCW. Repeat until
picture has bright whites, proper black level and acceptable contrast with no blooming or raster
bounce.
Luminance Peaking Control
The Luminance Peaking adjustment is made using the internal Crosshair pattern and the tuner on
a live channel. RP1, Peak Luminance control, is located on the Video Processor Panel next to
the Comb Filter.
1. Set the Picture control to midrange.
2. Set the Brightness control to midrange.
3. Set the Sharpness control to full CW.
4. Adjust RP1 until minimum ringing occurs at the left edge of the vertical line.
NOTE: These troubleshooting charts can not be all inclusive. They are meant to be a service
guide only. There are several safety and/or protection circuits in the set which, if activated, can
resemble or mask the actual defect. One such circuit is the vertical failsafe circuit which can
cause a loss of video. Use of the service manual will be needed to resolve this type of problem.
