Adjusting The Focus - Ikegami HTM-1517R Operation Manual

(4) Adjusting the color balance
a) Color balance
For the component signal (YPbPr/RGB), adjust the
color balance using CHROMA only. If the decoder
module DE-801 or DE-811 is mounted, input NTSC
composite signal, and adjust the color balance us-
ing HUE/CHROMA.
b) Adjustment procedure 1 (NTSC composite signal)
① Input signal
Input SMPTE color bar signal or the NTSC 75%
color bar signal similar to it.
e a
f b
Fig. 4-6-3. NTSC 75% Color Bar Signal
② Starting
Set the screen to blue only using the SCREEN
switch.
* As the luminance difference is hard to discern
when the screen is bright, dim the surroundings
as much as practical and lower the BRIGHTNESS
manually until the blue signal is slightly visible.
This will help make more accurate adjustment.
③ Adjusting HUE
Adjust HUE so that the parts a to d in Fig. 4-6-
3 become the same brightness.
If they do no become the same brightness, set to
the optimum state, and next adjust CHROMA.
④ Adjusting CHROMA
Adjust CHROMA so that the parts e to h in Fig.
4-6-3 become the same brightness.
If they do no become the same brightness, set to
the optimum state, and adjust the HUE as de-
scribed in step ③ .
⑤ Repeat adjustments ③ and ④ until a to h be-
come the same brightness.
c) Adjustment procedure 2 (Component signal)
① Input signal
Input the 100% color bar signal to the YPbPr in-
put.
a b
Fig. 4-6-4. 100% Color Bar Signal
Blue
c g
d h
Black
c d
② Starting
Set the screen to blue only using the SCREEN
switch.
* As the luminance difference is hard to discern
when the screen is bright, dim the surroundings
as much as practical and lower the BRIGHT-
NESS manually until the blue signal is slightly
visible. This will help make more accurate ad-
justment.
③ Adjusting CHROMA
Adjust CHROMA so that the parts a to d in Fig.
4-6-4 become the same brightness.
If the input signal is 75% color bar signal ( a is
100% white and the parts b to d are 75%), adjust
CHROMA so that the parts b to d become the
same brightness.

(5) Adjusting the focus

a) Focus
Fig. 4-6-5. Flyback transformer
b) Precautions
The flyback transformer provides the CRT with 26-
kV high voltage. Only qualified service engineers
may access this device. Enough care must also be
paid not to touch any other parts than the con-
trols.
c) Adjustment procedure
① Starting
Turn off the power and detach the monitor's top
cover. Turn on the power again and heat-run the
transformer for about 20 minutes.
② Input signal
Select a fine signal that gets characters displayed
over the entire screen or a character signal among
the built-in test signals.
③ Adjusting FOCUS
Adjust FOCUS 2 (static focus) in Fig. 4-6-5 to op-
timize the focus at the screen center. Adjust FO-
CUS 1 (dynamic focus) to adjust the focus at the
screen corners. The FOCUS 1 and 2 affect each
other. Adjust these focus controls alternately until
the optimum focus is achieved over the entire
screen.
29
FOCUS (dynamic)
FOCUS (static)
SCREEN