Purity Adjustment - Sylvania 6319CCB Service Manual

11. Head Switching Position
Adjustment
Purpose: Determine the Head Switching Point during
Play back.
Symptom of Misadjustment: May cause Head Switch-
ing Noise or Vertical Jitter in the picture.
Note: Unit reads Head Switching Position automat-
ically and displays it on the screen (Upper Left Corner).
1. Playback test tape (FL8A, FL8N).
2. Enter the Service Mode. (See page 1-4-1)
Then press the number 5 button on the remote
control unit.
3. The Head Switching position will display on the
screen; if adjustment is necessary follow step 4.
6.5H(412.7µs) is preferable.
4. Press "CH " or "CH
control unit if necessary. The value will be changed
in 0.5H steps up or down. Adjustable range is up to
9.5H. If the value is beyond adjustable range, the
display will change as:
Lower out of range; 0.0H
Upper out of range; -.-H
5. Turn the power off and on again.
12. CCS Text Box Location
When replacing the CRT, the CCS Box might not stay
in appropriate position. Then, replace micro computer.
Note: This adjustment automatically done by the micro-
computer.
" button on the remote
The following 2 adjustments normally are not at-
tempted in the field. They should be done only when
replacing the CRT then adjust as a preparation.

13. Purity Adjustment

Purpose: To obtain pure color.
Symptom of Misadjustment: If Color Purity Adjust-
ment is incorrect, large areas of color may not be
properly displayed.
Test Point Adjustment Point
Deflection Yoke
---
Purity Magnet
Tape
--- Pattern Generator
GREEN
* This becomes RED COLOR if push 7KEY with a
service mode.
1. Set the unit facing east.
2. Operate the unit for over 30 minutes before adjust-
ing.
3. Fully degauss the unit using an external degaussing
coil.
4. Set the unit to the AUX Mode which is located before
CH2 then input a red raster from video in.
5. Loosen the screw on the Deflection Yoke Clamper
and pull the Deflection Yoke back away from the
screen. (See Fig. 6)
6. Loosen the Ring Lock and adjust the Purity Magnets
so that a red field is obtained at the center of the
screen. Tighten Ring Lock. (See Fig. 5,6)
7. Slowly push the Deflection Yoke toward the bell of
the CRT and set it where a uniform red field is
obtained.
8. Tighten the clamp screw on the Deflection Yoke.
1-7-5
Mode
---
M. EQ. Spec.
See below.
Figure
RED
Input
*Red Color
BLUE
Fig. 5
T7200EA