5-4. MA BOARD ADJUSTMENTS
H. Frequency (Free Run) Check
1.Input a TV mode (RF) with no signal.
2.Connect a frequency counter to base of Q501
3.Check H. Frequency for 15735 ± 200 Hz
V. Frequency (Free Run) Check
1.Select video 1 with no signal input.
2.Set the conditions for a standard setting.
3.Connect the frequency counter to
CN501pin 
(V DY+) and ground on the A Board .
4.Check that V. Frequency shows 60 ± 4 Hz.
Drive (RDRV)
1.Input a
2.In Standard mode, set PICTURE to maximum and COLOR to minimum.
3.Activate the Service Adjustment Mode.
4.Set both GON and BON items. Using 
and 
; set each to the following values. Leave RON set to “1”.
SERVICE RON 1
1: ON
0: OFF
R ON: | ON | (1) |
G ON: | OFF | (0) |
B ON: | OFF | (0) |
5.Connect an oscilloscope probe to CA Board, J701 Pin 12 (KR) (Red Out) .
6.Select RDRV with 
and 
.
7.Adjust the value of RDRV with 
and 
for 92.5 ± 3 VDC.
8. Reset GON and BON values to “1”.
R ON: | ON | (1) |
G ON: | ON | (1) |
B ON: | ON | (1) |
9. Reset Picture and Color to normal values:
PICTURE: MAX
COLOR: CENTER
10. Press 
then 
to save into the memory.
Display Position Adjustment (DISP)
1.Input a
2.Set to Service Adjustment Mode.
3.Select DISP with 
and 
.
4.Adjust values of DISP with 
and 
to adjust characters to the center.
5.Write to memory by pressing 
then 
.
6.Check to see if the text is displayed on the screen.
SERVICE DISP 15
Sub Bright Adjustment (SBRT)
1.Input a monoscope signal.
2.Activate the Service Adjustment Mode.
3.Set the PICTURE and BRIGHTNESS to minimum.
4.Select the SBRT item with 
and 
.
5.Adjust the values of SBRT with 
and 
to obtain a faintly visible crosshatch.
6.Press 
then 
to save into the memory.
Sub Hue, Sub Color Adjustment (CHUE, CCOL)
1. Input a
2. Activate the Service Adjustment Mode.
3. Connect an oscilloscope probe to CA Board, CN705 Pin 
.
4. Select the CHUE and CCOL item with 
and 
.
5. | While showing the CHUE item, adjust the waveform with | |||
| and | until the second and third bars show the same level | ||
| (V2 = V3 < 0.1 |
|
| |
6. | While showing the CCOL item, adjust the waveform with | |||
| and | until the first and fourth bars show the same level | ||
| (V1 = V4 < 0.1 | V2V3 | V4 | |
7. Press 
then 
to save into the memory.
V. Size Adjustment (VSIZ)
1.Input a crosshatch signal.
2.Activate the Service Adjustment Mode.
3.Select the VSIZ item with 
and 
.
4.Adjust value of VPOS with 
and 
for the best vertical center.
5.Press 
then 
to save into the memory.
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