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68 CRT Management
CRT Management Overview
Controlling the beam with scan is one aspect of displaying a proper video on a CRT.
Beam current must also be controlled in a defined fashion to provide video true to
the original signal or to provide video closer to an "ideal" perception of the original
signal. The MM101 uses several circuits after final video processing to properly set
up the CRT to receive video data and peak CRT performance for the specific visual
display. SVM (Scan Velocity Modulation) modulates scan to increase apparent
contrast of high frequency luminance video. As with previous chassis' the MM101
employs an AKB (Automatic Kine Bias) system to track and compensate for the
normal drift in beam current cutoff bias of a CRT. The MM101 uses a Dynamic
Focus circuit to optimize the corner focus of CRT's 27" and larger. Dynamic Focus
modulates or "varies" the voltage to the CRT focus grids with a horizontal and vertical
parabola signal.

Scan Velocity Modulation
SVM for the MMC101G/MMC102(G) is unchanged from the original MM101.

Dynamic Focus
Dynamic Focus in the MMC101G is used to correct the focus of the electron beam as the
distance between the electron gun and the phosphor surface changes. In other words,
without dynamic focus or dual focus, if beam focus was adjusted to provide optimal focus
of the horizontal scan lines vertical lines may look slightly soft. If the beam was adjusted
for optimal vertical lines, horizontal detail may look soft. Some compromise was required.
Dual focus grids are used to optimize focus in the vertical and horizontal direction. Fixed
voltages on the two focus grids control the electron beam shape. One optimizes vertical
picture elements, the other optimizes horizontal picture elements. This is used in the
traditional "Dual Focus" CRT's, however it still results in some compromise. Dynamic
focus modulates the voltage difference between the two focus grids such that focus
uniformity is achieved over the entire picture.

MMC102(G) Dynamic Focus
Basically the topology of Dynamic Focus for the MMC102(G) is the same as the
MMC101G, but the amount of vertical modulation is less. Phasing of the horizontal
parabola is slightly changed due to the different mechanical geometry of the projection
instruments. There are some value changes in components to accomplish this.
Also notable is the absence of the single focus/screen assembly. The lead from the
output of dynamic focus transistor Q14730-E is connected to the regulator
PTV focus/screen block which contains screen controls and DC focus pots for the
three separate PTV CRT's.
CRT Management 69
CRT Drivers
The CRT driver circuit for the MMC101G/MMC102(G) is unchanged from the original
MM101 circuitry. It consists of three single IC video amplifiers and supporting components.
Each IC is a single 30MHz bandwidth, 125Vp-p video output amplifier contained in
a 13 pin single in-line (SIL) package. The device was specifically designed to drive
CRT cathodes in high-end and HDTV capable television applications.
The device is suited for operation in the MMC101G due to its wide bandwidth, high
power output, low static power draw (app. 2.5W), excellent protection against Kine arcs
and power supply glitches and a cathode current measurement output, labeled Ik, normally
used for Automatic Kinescope Bias (AKB). The Ik output level does not match the video
processor IC AKB sense input level and requires some level shifting to be useful.
The direct view models (MMC101G) will use AKB. Projection models (MMC102(G))
will have AKB disabled and any parts required only for AKB will not be loaded on the
PCB. Otherwise AKB circuitry is unchanged.

Grid Kick
The MMC101G/MMC102(G) will continue to use the "grid kick" circuit to prevent after
glow. When the +12V or +205V supply is removed, the cathode output at pin 12 is
clamped to ground which may cause after glow. Beam current may still flow, but with no
scan and diminishing focus voltage, it appears as an out of focus "blob" in the center of the
screen. In severe cases, if focus voltages hold, it may damage the phosphor. Projection
CRT's have used some form of beam current cutoff for several generations. The MM101
drives the CRT harder than previous chassis and therefore utilizes the grid kick circuit to
ensure beam current cutoff at shut down or with the loss of run supplies.

Further Information
Consult TCE Technical Publication T-MM101-1 for further information on SVM, AKB,
Grid Kick and Dynamic Focus.
70 CRT Management
Color Temperature Alignments
Color temperature for the MMC101G/MMC102(G) becomes slightly more tedious than
the original MM101. For the direct view alignment very little has changed, however for
the projection MMC102(G) alignment becomes somewhat complex requiring additional
patience for field adjustments.
Ideally, to place an instrument back to factory specifications, a color light output meter
should be used for exact alignment, but it is realized that not every shop will have such an
instrument. Alignments will be given for the majority of repair facilities and the values for
light output meters will be noted for those who have access to that equipment.
The following alignments should be performed in the order written, each section completed
prior to beginning the next. Exact patterns are shown in the following illustrations.
Recommended substitutes will also be noted.

Alignment Order

1. Screen Control Setup
2. 2.14H "Video" Mode, "Normal" Temperature.
3. 2.14H, "Video" Mode, "Warm" Temperature.
4. 2.14H, "Text" Mode, "Normal" Temperature.
5. 2.14H, "Text" Mode, "Warm" Temperature.
6. 1H, "Normal" Temperature
7. 1H, "Warm" Temperature

TECH Color Temperature Shift
TIP
In direct view (MMC101G) chassis' a noticeable shift in color temperature may occur
during the initial CRT warm-up period at start-up. If it is noticed at about 6-8 seconds
after power is turned on, the shift is normal. This is when the factory settings for AKB
are downloaded to the video processor. The factory settings are values aligned and
stored in the EEPROM at the time of manufacture and cannot be changed without
Chipper CheckTM. They carry AKB thru the first 10-15 seconds of operation. At that
time, AKB begins to take over adjusting the CRT cutoffs to current conditions. As the
CRT ages, the original factory values may no longer provide an acceptable picture
during the warm-up period, but as soon as AKB begins working, it will adjust the CRT
back to acceptable color temperature.
CRT Management 71

Figure 7-1, Typical Staircase Pattern

Color Temperature Alignment Patterns
Color temperature alignment for the MMC101G will vary only slightly from the previous
MM101 chassis. Some form of staircase pattern similar to Figure 7-1 will be required.
Proper identification of the "0" (if available) and "7.5" or "setup" bars on screen and the
waveform produced at the cathodes of the CRT will be needed. Consult the specification
manual for the pattern generator to confirm the location of these bars.
The oscilloscope waveform shows the relationship between the bars and the video signal
at the cathodes of the CRT. This waveform is present on all three cathodes. With the
oscilloscope adjusted to provide a full peak to peak readout of the waveform at the
horizontal rate, the 7.5 IRE setup bar will be the critical area. Be certain this bar can be
identified using the equipment available. If a 7.5 IRE bar is not available, 10 IRE may be
used.
It should also be noted that bar patterns differ. Some vary from 10 to 100 IRE in various
steps and in different directions, but most should have an identifiable 7.5 or 10 IRE bar.
72 CRT Management
Direct View Screen and Color Temperature Setup
As with previous AKB systems, there is no direct AKB setup. AKB is automatic and requires no
technician adjustments. However, the screen control must be setup and color temperature must be
adjusted to proper levels for AKB operation. AKB will then maintain the cutoff bias of the CRT
based on these initial adjustments.
There are additional color temperature related setups that must be performed prior to the final color
temperature alignments.

To Adjust the Screen Control:
NOTE: AKB will remain "ON" for screen control adjustment. Bias and drive settings should not
be changed unless the eeprom has been changed and no longer has the typical values for these
settings. The screen control alignment with AKB on is very accurate and not significantly
dependent on these bias/drive settings.
1. Apply a vertical gray bar staircase pattern (at least 8 bars from "7.5" to ">75" IRE similar to
Figure 7-1) to the video input and adjust the set for operation from that input. Identify the "7.5"
IRE bar location both on-screen and using an oscilloscope. The 7.5 IRE bar is "black" or
"cutoff" and will be used for reference. On most patterns, the remainder of the bars will
progressively become brighter.
2. Use the "Reset" function on the consumer picture quality controls to place black level, contrast,
color, tint and sharpness to their nominal factory default settings. Use the "Picture Presets" to
place the set in "Normal Lighting" mode.
3. Allow the instrument to warm up with the staircase pattern or active video on screen for at least
15 minutes. Make certain the staircase pattern is again on screen before proceeding.
4. Using an oscilloscope, measure all three CRT cathode voltages and identify the cathode whose
"7.5" IRE pattern is the greatest.
5. Connect the oscilloscope probe to the cathode identified in step 4. Slowly adjust the Screen
Control until the 7.5 IRE bar is at 170V.
6. Do not change the screen control after this setup is complete. Any further adjustments will be
done with the color temperature controls.
Measuring CRT Cathodes
It is difficult to monitor cathode voltage with the shield on the Kine driver board. Oscilloscope
probes may also cause some loading error. To assist the technician in performing these
measurements, a test lead may be made using a 2200-3300 ohm 1/2 Watt resistor with an alligator
or hook type clip soldered to one lead. The clip will easily connect to the end of R15116 (Red),
R15126 (Green) or R15136 (Blue) where they connect to the Kine driver IC U15101/02/03 at pin
13. These resistors are easy to locate and connect to from the open side of the shield. They are
mounted on metal standoffs next to the IC's. This test point will give an accurate measurement of
cathode voltages. Once the highest cathode is determined, the connection to this cathode is used to
set the "0 IRE" or "7.5 IRE" cathode voltage by adjusting the screen control.
NOTE: The connection between the clip and the resistor should be fairly short. The connection
between the resistor and the probe can be longer. It may be easier to have three lead assemblies,
connecting all three prior to screen adjustment. The probe should be at least 10x or 100x.
CRT Management 73

170V

Figure 7-1, Typical Staircase Pattern (Repeated)
Color Temperature Background
The purpose of color temperature setup is to assure uniform gray level from black to the
brightest scenes. If a uniform gray screen is displayed, no matter the brightness level, no
tinting in either the red, green or blue direction should be apparent. This is known as
"color tracking". Once the proper color temperature is set, AKB will maintain the cutoff of
the CRT to assure proper low light performance. Assuming color tracking of the CRT
does not change, this will also maintain the high level picture color temperature. 6500K is
a much "warmer" picture than 9300K conforming more closely to the original NTSC
standards. 9300K is much "brighter" resulting in an apparent brighter display at the
expense of shifting the color temperature towards blue.
There are two alignable user selectable color temperature settings, 6500K and 9300K.
Each requires color temperature and light output alignment. The 6500K alignment should
be performed first, followed by 9300K. YUV Cutoff or RGB Cutoff will be adjusted only
during the 6500K setup. A single adjustment is good for both temperature settings.
If a CRT or video processor IC has been replaced, the technician should perform
screen control alignment first. Then a critical evaluation of the color temperature
setup of the CRT should be done. In most cases, color temperature will be TECH
acceptable and not require alignment! TIP
74 CRT Management
Color Temperature Setup (YUV):
NOTE: Perform YUV Cutoff setup first.
1. Apply a vertical gray bar staircase pattern (at least 8 bars from "7.5" to ">75" IRE) to the
video input and adjust the set for operation from that input. Identify the 7.5 IRE bar
location. It is the "black" or "cutoff" bar. For these adjustments, this bar and the next
brighter bar will be used. On most patterns, the remainder of the bars will progressively
become brighter. If a CRT or main EEPROM has been replaced, use Chipper CheckTM
or the front panel menu to set the Red, Green and Blue "Cutoff" values to midrange.
2. If all three colors (red, green and blue) appear too dim or too bright, adjust "YUV
Cutoff" until any single color disappears from the black bar, but is still visible in
the adjacent bar. Note that color.
For instance, the black bar is plainly visible and close to gray. By decreasing the
YUV Cutoff control all three colors will begin to dim. Blue may be the first color to
disappear from the black bar, leaving a red/green (yellow) tint to the black bar.
YUV Cutoff adjustment should stop at this point.
3. Adjust the appropriate remaining red, green or blue "Cutoff " controls until any red, green
or blue tint disappears from the black bar, but is still visible in the adjacent bar. When
properly adjusted, the adjacent bar should be a very low level gray with no color tinting.
Low level color temperature setup is now complete.
4. Now observe the brighter portions of the bars. Adjust the red or blue drive controls to
remove any signs of red or blue tint in the higher brightness bars. Observe the bars for
signs of CRT overdrive. Overall brightness may be adjusted using the "YUV Light
Output" control. Some compromise may be required, but the higher IRE sections should
be as free from color tinting as possible. Color temperature setup is now complete.

>75 IRE 7.5 IRE >75 IRE
>75 IRE 7.5 IRE
"White" Shades of Gray "Black"
"White" "Black" "White"
Shades Shades
of Gray of Gray

Figure 7-2, Typical Grayscale Setup Patterns
CRT Management 75
Overall Brightness Levels (Drive)
There is no control for the green drive (high brightness). Even though there is a front panel
control to toggle the red drive to green, there is no EEPROM location to store the resulting
adjustment. Any value for green would be stored to the red location.
If overall brightness is not adequate, increase it by using the YUV Light Output control.
This control should not affect color temperature at this level, however large changes may
disturb the low brightness level color temperature (cutoff).
After high brightness alignment is complete always recheck low level brightness areas. If
color temperature is not acceptable, begin color temperature alignment again. Generally,
only small changes should be required at this time.

Color Temperature Setup (RGB):
There is no color temperature setup required for RGB mode. However, note the
brightness levels of RGB are generally lower than YUV for the same or similar inputs.
There are two reasons. First, consumers using the MMC101G as a computer monitor will
be sitting much closer than when viewing commercial program material on the same set.
Second, text characters tend to blur at high brightness levels. To be certain this does not
occur, the MMC101G reduces high brightness output levels in computer text mode. RGB
cutoff should be adjusted in the "Computer/Text" mode until the black bar is unlit, but
the adjacent bar remains slightly visible. RGB Light Output is more subjective and critical
for the reasons given above. Light output should be set so the brightness of the brightest
bar is 1/2 the level of the same bar in YUV mode. If a light output meter is available,
measure the output level of the brightest bar in YUV mode. Then adjust "RGB Light
Output" to provide the brightness level of the same bar approximately 1/2 the YUV level.
If no light meter is available, the adjustment is left to the technicians judgement.
76 CRT Management
AKB Troubleshooting (MMC101G Only)
Diagnosing AKB problems can be troublesome. The AKB pulses occur on lines 20, 21
and 22 of video. Unless test equipment can be procured allowing a technician to view
each of the lines individually, the AKB pulses cannot be viewed directly.
Failure of AKB to maintain cathode bias levels will result in incorrect color complaints.
More than likely it will be in the area of low illumination scenes tinted towards or away
from a specific color.
As with any "wrong color" complaints, traditional troubleshooting techniques may be
applied. Check the RGB output waveforms and voltages, then continue to the CRT
cathode and grid voltages. Finally check the CRT cathode drive waveforms. If all these
are acceptable, suspect CRT problems. If not, troubleshoot the appropriate circuits.
Placing a static pattern on the screen will allow measurement of DC voltages in the AKB
circuits. The level shift components expect a 4-6V pulse from the CRT drivers and deliver
a 1-2V pulse to the video processor IC. If the incoming pulse is too high or low, suspect
CRT driver problems. If the incoming pulse is OK, but the pulse to the video processor is
too high or too low, suspect component failure in the level shift circuitry. If all waveforms
and voltages agree with service data, suspect the video processor IC.
If AKB fails, as the CRT is warming up, a picture (or static depending upon input
selection) may appear for a short time. At about 6-8 seconds, (coinciding with the start of
AKB operation), the screen will either go black, or abnormally bright. The first check
should be at the video processor IC, U22300-56. This is the AKB feedback pulse from
the CRT drivers. Although the technician will not be able to look at the AKB pulses
directly, some sort of pulses about 2Vp-p would indicate the AKB level shift circuits were
working properly. If they are present, suspect the video processor IC.
An oscilloscope probe connected directly to the CRT cathode may cause a measurement
error because of the interaction of AKB with the probe, not just loading. The probe
connection changes the current that AKB measures and can cause as much as a 10V
error. Always follow the recommendation "Measuring CRT Cathodes" of this
chapter for measuring cathode voltages.
CRT Management 77

Notes/Comments/Nominal
Parameter # Parameter Name Value Range
Values
01 Error Detection (1st)

02 Error Detection (2nd)

03 Error Detection (last)

18 Red Cutoff 00 .. 255
19 Green Cutoff 00 .. 255
20 Blue Cutoff 00 .. 255
21 Video Mode Cutoff 00 .. 255
22 Red Drive 00 .. 127
23 Blue Drive 00 .. 127
Video ModeLight
24 00 .. 117 Adjusts all three drives
Output
25 Text Mode Cutoff 00 .. 127
26 Text Mode Light Output 00 .. 127
27 AKB Mode 00 .. 01 00=Off 01=On
28 Red Cutoff 00 .. 255
29 Green Cutoff 00 .. 255
30 Blue Cutoff 00 .. 255

31 Cutoff (Over ride) 00 .. 255

41 RGB Output Mode 00 .. 02 00=Norm 02=Green Only

Figure 7-3, Service Menu Color Temperature Adjustment Locations
78 CRT Management
MMC102(G) Color Temperature Alignment
Color temperature alignment for the MMC102(G) projection instrument becomes complex.
AKB is not utilized in this instrument and color temperature must be setup for two different
deflection modes, 1H and 2.14H, and both user selectable color temperature modes, "Normal"
and "Warm".
Color temperature is actually setup for only one deflection and user mode, then the remainder of
the settings are calculated and placed into the proper EEPROM locations. Proper color
temperature setup is dependant upon screen control setup. This adjustment is done only once and
used as a "reference" for the remaining adjustments.
The order of adjustment is important. The proper order is:
1. Screen Control Setup
2. 2.14H "Video" Mode, "Normal" Temperature.
3. 2.14H, "Video" Mode, "Warm" Temperature.
4. 2.14H, "Text" Mode, "Normal" Temperature.
5. 2.14H, "Text" Mode, "Warm" Temperature.
6. 1H, "Normal" Temperature
7. 1H, "Warm" Temperature

NOTE: The following procedures are for the MMC102(G) only and should not
be used for any other MM(C) chassis. Values that are for the MMC102 will be
in ().
Screen Control Setup
If screen control setup is done properly, the original color temperature settings will probably be
acceptable.
NOTE: AKB will remain "OFF" (0) for all operating conditions of the MMC102(G) including all
alignment procedures. AKB is not used in the MMC102(G) instrument at this time.
PRESETS:
To begin, set the instrument to receive a "VGA" input on the VGA2/DTV rear jack panel using a
clean average video signal. Preheat the instrument for at least 20 minutes with an active video
display.
In the consumer menu, under Picture Quality, set the Picture Presets to "Normal Lighting". Then
using the Picture Controls, set Contrast to "maximum" and Color to "minimum". Set Color
Warmth to "Normal". Also in Picture Quality, set the Picture Mode to "Video".
In the consumer menu under Screen, set the Menu Background Color to "Transparent".
Four test patterns, each available in 1H and 2.14H deflection modes, will be required for the
procedure. TP1 is a 12 IRE 50% display window for setting the screen controls and lowlights. TP2
is a 0 IRE flat field for setting cathode cutoffs. TP3 is a 100 IRE flat field for setting highlights. TP4
is a 100 IRE 50% Window for setting light output.
CRT Management 79

50% 12 IRE
Window Pattern
Test Pattern TP1

50% 100 IRE
Window Pattern
Test Pattern TP4

Figure 7-4, Window Patterns for Color Temperature Setup
80 CRT Management
To Adjust the Screen Control:
1. Apply TP1 to the VGA2/DTV input.
2. Make certain the preheat and preset conditions have been met.
3. Enter the serviceman menu using the front panel buttons by pressing and holding "MENU",
then pressing and releasing "POWER". Finally press "VOL UP" and simultaneously
release "VOL UP" and "MENU". Use "VOL UP" to place the "V:" value to "76". When
a parameter is specified use "CH UP" or "CH DN" to change to the correct parameter
number, then use "VOL UP" or "VOL DN" to change the value of the parameter.
4. Set all three screen controls on the focus/screen assembly to minimum (full CCW).
5. Set Video Mode light output (P24) to V:64
6. Set Blue Drive (P23) to V:64.
7. Set Red Drive (P22) to V:64.
8. Set Video Mode Cutoff (P21) to V:64.
9. Set Blue Cutoff (P:20) to V:127.
10. Set Green Cutoff (P:19) to V:127.
11. Set Red Cutoff (P:18) to V:127.
12. Making certain the 0 IRE Flat Field pattern (TP2) is still displayed, observe the LED's located
on the Kine boards on the neck of the CRT's. Adjust the Video Mode Cutoff (P21) until any
LED illuminates. Continue increasing P:21 until the second of the three LED's illuminates. It
does not matter at this point if the first LED goes dim.
13. Now adjust the Red, Blue or Green cutoff control for the LED THAT HAS NOT YET
ILLUMINATED until that LED also lights.
NOTE: If the cutoff control runs out of range, increase the Video Mode Cutoff (P:21) until
the final LED lights.
14. Now decrease the two remaining cutoff controls until the respective LED's are just lit.
15. Continue fine adjustment of the Red, Green and Blue cutoff controls until all three LED's are
full on.
16. If a colorimeter is available adjust the screen controls for x=.300, y=.310 and Y=1.00 +0.50.
If not, increase the screen controls to provide a low level gray pattern. A 10 Bar Gray Scale
or similar pattern may be used to provide a known gray pattern. The important point is when
the adjustment is complete a very low level uniform gray pattern should be visible when the flat
field gray pattern (TP2) is placed on the screen.
DO NOT ADJUST THE SCREEN CONTROLS AGAIN AFTER THIS STEP!!!
17. Exit the serviceman menu by pressing "POWER" on the front panel or remote control. This
stores the new values to the EEPROM and completes screen control setup.
If a colorimeter is not available color temperature setup and screen control adjustment should end
here. If a colorimeter is available continue to the next section.
CRT Management 81
To Adjust 2.14H "Video" Mode "Normal" Color Temperature:
1. Apply TP1 to the VGA2/DTV input and adjust the instrument for normal reception.
2. Make certain the preheat and preset conditions have been met. In the consumer
menu, under Picture Quality, set the Picture Presets to "Normal Lighting".
Then using the Picture Controls, set Contrast to "maximum" and Color to
"minimum". Set Color Warmth to "Normal". Also in Picture Quality, set the
Picture Mode to "Video".
3. Enter the serviceman menu using the front panel buttons by pressing and
holding "MENU", then pressing and releasing "POWER". Finally press
"VOL UP" and simultaneously release "VOL UP" and "MENU". Use "VOL
UP" to place the "V:" value to "76". When a parameter is specified use "CH
UP" or "CH DN" to change to the correct parameter number, then use "VOL
UP" or "VOL DN" to change the value of the parameter.
4. Set the RGB Output Mode (P:41) to V:2. This changes the screen output to
green only.
5. Using the colorimeter, adjust Video Mode Cutoff (P:21) for Y=0.420.
6. Change the video test pattern to TP3 (100 IRE Flat Field). Measure the light
output with the colorimeter and record as LO#1_____ .
7. Change the video test pattern to TP4 (100 IRE Window). Measure the light LO#1 _____
output with the colorimeter and adjust the Video Mode Light Output (P:24)
to obtain a reading 1.78 (3.0) times LO#1. Record it as LO#2______ .
Note: This should make Green peak at aproximately 3.44mA (3.8mA).
LO#2 _____
8. Change the video pattern back to TP1 and repeat step 6-7 if necessary.
9. To return all three colors, set RGB Output Mode (P:41) to V:0.
10. Change the video test pattern to TP1 (12 IRE Window) and adjust the Red, Green
and Blue Cutoffs (P:18, P:19 and P:20) and Video Mode Cutoff (P:21) using the
colorimeter for x=0.300, y=0.310, Y=0.600.
11. Change the video test pattern to TP3 (100 IRE Flat Field). Set highlight temperature
using the Red and Blue Drives (P:22 and P:23) for x=0.300, y=0.310.
12. Repeat steps 10 and 11 as needed for accuracy.
13. Record the values for P:18, P:19, P:20 and P:21, then transfer P:18 to P:28, P:19
to P:29, P20 to P:30 and P:21 to P:31.
14. Record the values for P:18, P:19, P:20, P:21, P:22 , P:23 and P:24 to be used in P:18 _____
Video Mode "Warm" adjustment.
P:19 _____
15. Exit the serviceman menu by pressing "POWER" on the front panel or remote
P:20 _____
control.
P:21 _____
16. Enter the customer menu, select "Color Warmth". Change from "Normal" to
P:22 _____
"Warm" then back to "Normal" to set the correct cutoff values. P:23 _____
P:24 _____
82 CRT Management
To Adjust 2.14H "Video" Mode "Warm" Temperature
Light Output:
1. Set the instrument to receive a "VGA" input on the VGA2/DTV rear jack panel using
a clean average video signal. Preheat the instrument for at least 15 minutes with an
active video display.
2. In the consumer menu, under Picture Quality, set the Picture Mode to "Video",
set Contrast to "maximum", "Color" to "minimum", Color Warmth to "Warm".
3. In the consumer menu under Screen, set the Menu Background Color to
"Transparent".
4. Enter the serviceman menu using the front panel buttons by pressing and holding
"MENU", then pressing and releasing "POWER". Finally press "VOL UP" and
simultaneously release "VOL UP" and "MENU". Use "VOL UP" to place the "V:"
value to "76". When a parameter is specified use "CH UP" or "CH DN" to change
to the correct parameter number, then use "VOL UP" or "VOL DN" to change the
value of the parameter.
5. Set P:18, P:19, P:20, P:21, P:22, P:23 and P:24 to the values recorded in the
previous 2.14H "Normal" setup step 15.
6. Change the video test pattern to TP1 (12 IRE Window) and adjust the Red, Green
and Blue Cutoffs (P:18, P:19 and P:20) and Video Mode Cutoff (P:21) using the
colorimeter for x=0.313, y=0.329, Y=0.600.
7. Change the video test pattern to TP3 (100 IRE Flat Field). Set highlight temperature
using the Red and Blue Drives (P:22 and P:23) for x=0.313, y=0.329.
8. Repeat steps 6 and 7 as needed for accuracy.
9. Exit the serviceman menu by pressing "POWER" on the front panel or remote
control.

Note: The LED's on each CRT board may not stay lit after
alignments. DO NOT Readjust the screen controls or align the
cutoffs to get the LED's to light again.
CRT Management 83
To Adjust 2.14H "Text" Mode "Normal" Temperature
Light Output:
1. Set the instrument to receive a "VGA" input on the VGA2/DTV rear jack panel using a
clean average video signal. Preheat the instrument for at least 15 minutes with an active
video display.
2. In the consumer menu, under Picture Quality, set the Picture Mode to "Computer/
Text", set the picture presets to "Normal Lighting". Then using the picture controls set
Contrast to "maximum", Color to "minimum", Color Warmth to "Normal".
3. In the consumer menu under Screen, set the Menu Background Color to transparent.
4. Enter the serviceman menu using the front panel buttons by pressing and holding
"MENU", then pressing and releasing "POWER". Finally press "VOL UP" and
simultaneously release "VOL UP" and "MENU". Use "VOL UP" to place the "V:"
value to "76". When a parameter is specified use "CH UP" or "CH DN" to change to
the correct parameter number, then use "VOL UP" or "VOL DN" to change the value
of the parameter.
5. Set the RGB Output Mode (P:41) to V:2. This changes the screen output to green
only.
6. Change the video test pattern to TP4 (100 IRE Window) and adjust Text Mode Light
Output (P:26) to 1/2 the value recorded previously as LO#2. Record this value as LO#3 _____
LO#3______ .
7. Change the video test pattern to TP1 (12 IRE Window). Using the colorimeter,
adjust Text Mode Cutoff (P:25) for Y=0.420.
8. Repeat steps 6 and 7 as needed for accuracy. P:25 _____
9. Record the DAC values from P26 and P25 for use in the 2.14H Text Mode / Warm
P:26 _____
Color temp mode alignment.
10. Set the RGB Output Mode (P:41) to V:0. This returns the screen output to normal.
11. Exit the serviceman menu by pressing "POWER" on the front panel or remote control.
This should make the Green peak current approximately = 1.72mA (1.9mA)

Note: The LED's on each CRT board may not stay lit after
alignments. DO NOT Re-adjust the screen controls or align the
cutoffs to get the LED's to light again.
84 CRT Management
To Adjust 2.14H "Text" Mode "Warm" Temperature
Light Output:
1. Set the instrument to receive a "VGA" input on the VGA2/DTV rear jack panel using
a clean average video signal. Preheat the instrument for at least 15 minutes with an
active video display.
2. In the consumer menu, under Picture Quality, set the Picture Mode to "Computer/
Text", set the picture presets to "Normal Lighting". Then using the picture controls
set Contrast to "maximum", Color to "minimum", Color Warmth to "Normal".
3. In the consumer menu under Screen, set the Menu Background Color to
transparent.
4. Enter the serviceman menu using the front panel buttons by pressing and holding
"MENU", then pressing and releasing "POWER". Finally press "VOL UP" and
simultaneously release "VOL UP" and "MENU". Use "VOL UP" to place the "V:"
value to "76". When a parameter is specified use "CH UP" or "CH DN" to change
to the correct parameter number, then use "VOL UP" or "VOL DN" to change the
value of the parameter.
5. Set the Text mode cutoff P:25 and the Text Mode Light Output P26 to the values
recorded in 2.14H Text Mode Normal Temperature Light Output step 9.
6. Exit the serviceman menu by pressing "POWER" on the front panel or remote
control.
This should make the Green peak current approximately = 1.72mA (1.9mA).

Note: The LED's on each CRT board may not stay lit after
alignments. DO NOT Readjust the screen controls or align the
cutoffs to get the LED's to light again.
CRT Management 85
To Adjust 1H "Normal" Color Temperature:
1. Apply a pattern similar to TP1 to the VID1 input and adjust the instrument for normal
reception of this signal.
2. Preheat the instrument for at least 15 minutes with an active video display.
3. In the consumer menu, under Picture Quality, set the Picture Presets to "Normal".
Then using the Picture Controls, set Contrast to "maximum", Color to "minimum",
Color Warmth to "Normal".
4. Enter the serviceman menu using the front panel buttons by pressing and holding
"MENU", then pressing and releasing "POWER". Finally press "VOL UP" and
simultaneously release "VOL UP" and "MENU". Use "VOL UP" to place the "V:"
value to "76". When a parameter is specified use "CH UP" or "CH DN" to change
to the correct parameter number, then use "VOL UP" or "VOL DN" to change the
value of the parameter.
5. Set P:18, P:19, P:20, P:21, P:22, P:23 and P:24 to the values recorded in previous
2.14 "Video mode Normal" step 15, as a starting point.
6. Set the RGB Output Mode (P:41) to V:2. This changes the screen output to green
only.
7. Change the video test pattern to TP1 (12 IRE Window). Using a colorimeter,
adjust Green Cutoff (P:19) and Video Mode Cutoff (P:21) for Y=0.420.
8. Change the video pattern to TP4 (100 IRE Window). Using the colorimeter,
adjust Video Mode Light Output (P:24) to make the value 0.95 (.89) times LO#2
previously recorded in step 7 of the first alignment.
Note: This should make Green peak approximately 3.44mA (3.8mA).
9. Repeat step 8 to check for correct value of LO#2, and readjust Video Mode Light
Output P24 as needed.
10. Set the RGB Output Mode (P:41) to V:0. This changes the screen output to Red,
Green and Blue.
11. Change the video test pattern to TP1 (12 IRE Window) and adjust the Red, Green
and Blue Cutoffs (P:18, P:19 and P:20) and Video Mode Cutoff (P:21) using the
colorimeter for x=0.300, y=0.310, Y=0.600.
P:18 _____
12. Change the video test pattern to TP3 (100 IRE Flat Field). Set highlight temperature P:19 _____
using the Red and Blue Drives (P:22 and P:23) for x=0.300, y=0.310. P:20 _____
13. Repeat steps 11-12 if necessary.
P:21 _____
P:22 _____
14. Record the values for P:18, P:19, P:20, P:21, P:22, P:23 and P:24. These will be P:23 _____
used for the "Warm" temperature setup. P:24 _____
15. Exit the serviceman menu by pressing "POWER" on the front panel or remote
control.
Note: The LED's on each CRT board may not stay lit after
alignments. DO NOT Readjust the screen controls or align the
cutoffs to get the LED's to light again.
86 CRT Management
To Adjust 1H "Warm" Color Temperature:
1. Apply a pattern similar to TP1 to the VID1 input and adjust the instrument for normal
reception of this signal.
2. Preheat the instrument for at least 15 minutes with an active video display.
3. In the consumer menu, under Picture Quality, set the Picture Presets to "Normal".
Then using the Picture Controls, set the picture presets to "Normal Lighting". Then
using the picture controls set Contrast to "maximum", Color to "minimum", Color
Warmth to "Warm".
4. Enter the serviceman menu using the front panel buttons by pressing and holding
"MENU", then pressing and releasing "POWER". Finally press "VOL UP" and
simultaneously release "VOL UP" and "MENU". Use "VOL UP" to place the "V:"
value to "76". When a parameter is specified use "CH UP" or "CH DN" to change
to the correct parameter number, then use "VOL UP" or "VOL DN" to change the
value of the parameter.
5. Set the values for P:18, P:19, P:20, P:21, P:22, P:23 and P:24 to those recorded in
step 14 of 1H Normal Color Temperature adjustment.
6. Change the video test pattern to TP1 (12 IRE Window) and adjust the Red, Green
and Blue Cutoffs (P:18, P:19 and P:20) and Video Mode Cutoff (P:21) using the
colorimeter for x=0.313, y=0.329, Y=0.600.
7. Change the video test pattern to TP3 (100 IRE Flat Field). Set highlight temperature
using the Red and Blue Drives (P:22 and P:23) using the colorimeter for x=0.313,
y=0.329.
8. Repeat step 6 and step 7 as necessary for accuracy.
9. Exit the serviceman menu by pressing "POWER" on the front panel or remote
control.
10. Enter the customer menu, select "Color Warmth". Change from "Warm" to
"Normal" then back to "Warm" to set the correct cutoff values.

Note: The LED's on each CRT board may not stay lit after
alignments. DO NOT Readjust the screen controls or align the
cutoffs to get the LED's to light again.
CRT Management 87

Conclusion
The purpose of screen control alignment is to match the electronic video signal to the CRT
electrical characteristics. In other words, if the video signal requires beam current to stop,
the CRT must know the respective voltage value that cause the cathodes to cutoff. Screen
control setup is an exact adjustment. If AKB is present, the adjustment may last the life of
the CRT. Screen control setup is more favorable to proper adjustment.
On the other hand, color temperature can be perceived differently depending upon room
lighting and environment, original program material, electrical adjustment of the video
processing and control circuits and finally, the viewer. What looks red to a technician,
may look purple or orange or any other color to another viewer. The technician should
strive to provide a "trained" eye by knowing what proper color tracking is. Color
temperature alignment is actually striving for a uniform gray, with no hint of color tinting, as
the ideal for any light output level of the CRT. If the CRT is properly tracking the gray
level, colors will normally be reproduced faithfully.