Sony Ba5 Service Manual

— 11 —
KV-25FS12 / 25FS12C
2-2.  CONVERGENGE
Before starting convergence adjustments:
1  Perform FOCUS, VLIN and VSIZE adjustments.
2.  Set BRIGHTNESS control to minimum.
3.  Feed in dot pattern.
VERTICAL STATIC CONVERGENCE
1.  Adjust V. STAT magnet to converge red, green and blue dots in the 
center of the screen (Vertical movement adjust V.STAT RV701 to 
converge).
B G R
Center dot
R   G   B
V.STAT magnet
RV701
V.STAT
2.  Tilt the V. STAT magnet and adjust static convergence to open or close 
the V....

— 12 —
KV-25FS12 / 25FS12C
DYNAMIC CONVERGENCE  ADJUSTMENT
Before performing this adjustment, perform Horizontal  and Vertical Static 
Convergence Adjustment.
1.  Slightly loosen defl ection yoke screw.
2.  Remove defl ection yoke spacers.
3.  Move the defl ection yoke for best convergence as    
shown below:
RGB
BGR
RGB
RR
R GB
G
BG
B RG B BGR
R
G
BR GB
BGR RGB
4.  Tighten the defl ection yoke screw.
5.  Install the defl ection yoke spacers.
TLH PLATE A DJUSTMENT
1.  Input crosshatch pattern.
2.  Adjust...

— 13 —
KV-25FS12 / 25FS12C
2-5. METHOD OF SETTING THE SERVICE 
ADJUSTMENT MODE
SERVICE MODE PROCEDURE
1.  Standby mode (power off).
2.  Press 
Display  Channel 5  Sound Volume +  Power 
on the Remote Commander (press each button within a second).
SERVICE ADJUSTMENT MODE ON
1.  The CRT displays the time being adjusted.
ModeCategoryDisplay
ItemDisplay
Item
Signal
Typentscservice
defl
vchp
00000000
00000000 hsiz 16
2.  Press 1
 or 4
 on the Remote Commander to select the time.
3.  Press 
3
 or 6
 on the...

— 14 —
KV-25FS12 / 25FS12C
HOLD-DOWN READJUSTMENT
If the setting indicated in Step 2 of Hold-Down Operation Confi rmation 
cannot be met, readjustment should be performed by altering the 
resistance value of R564 component marked with 
X. 
+
IABL ABLT505
FBT
range
-
ammeter
3.0 mA  DC
A
3-2. B+ VOLTAGE CONFIRMATION AND 
ADJUSTMENT
Note: The following adjustments should always be performed when 
replacing the following components, which are marked with 
Y on the 
schematic diagram on the A Board:
  
 A...

— 15 —
KV-25FS12 / 25FS12C
R438
R438R438 R438
R522
R522R522 R522
R541
R541R541 R541 R450
R450R450 R450
R445
R445R445 R445
C611
C611C611 C611
C448
C448C448 C448R449
R449R449 R449
R454
R454R454 R454
C213
C213C213 C213R527
R527R527 R527
R525
R525R525 R525
R514
R514R514 R514R567
R567R567 R567R225
R225R225 R225 R529
R529R529 R529C530
C530C530 C530
C546
C546C546 C546R563
R563R563 R563R218
R218R218 R218R227
R227R227 R227C542
C542C542 C542 C541
C541C541 C541
C518
C518C518 C518R231
R231R231 R231 R232
R232R232...

— 16 —
KV-25FS12 / 25FS12C
4-1. SETTING THE SERVICE ADJUSTMENT 
MODE
1.  Standby mode (Power off).
2.  Press the following buttons on the remote commander within a 
second of each other: 
 
Display  Channel 5  Sound Volumne +  Power
SERVICE ADJUSTMENT MODE ON
1.  The CRT displays the item being adjusted.
service     defl     hsiz 16
ntsc
vchp     00000000    00000000CategoryDisplay 
Item
ModeItem 
Data
Signal
Type
2.  Press 1
 or 4
 on the Remote Commander to select the item.
3.  Press 
3
 or 6
 on the...

— 17 —
KV-25FS12 / 25FS12C
ADJUSTMENT ITEMS (1 OF 2)
Reg # ITEM FUNCTION RANGEFIX    
DATA NTSC VIDEO RFAVERAGE 
DATA
1 HSIZ  Horizontal Size Adjustment 0-63 35
38
2 HPOS Horizontal Position Adjustment 0-63 3321
3 VBOW Vertical Line Bowing Adj. 0-15 59
4 VANGVertical line Bowing Slant Adj. 0-15 75
5 TRAP Horizontal Trapezoid Adj. 0-15 77
6 PAMP Horizontal PIN  Distortion Adj. 0-63 732
7 UPIN Upper PIN Distortion Adj. 0-63 3639
8 LPIN Lower PIN Distortion Adj. 0-63 3639
9 VM Velocity Modulation On/Off...

— 18 —
KV-25FS12 / 25FS12C
ADJUSTMENT ITEMS (2 OF 2)
service     id’s      id5 19
ntsc
M37280MK-00SP VERB.OFunctionID
Number
ModeData
Signal
Type00010011
Chip 
Version
Reg # ITEM FUNCTION RANGEFIX 
DATA NTSC VIDEO RFAVERAGE 
DATA
53 SHPF SHARPNESS Circuit Fo 0,1
1
54 PREL Pre-Shoot / Over-Shoot 0,1 11
55 Y-DC DC Transmission Ratio Switching 0,11
56 GAMMGamma Correction Amnt 0-31
57 ABLM ABL Mode Switching 0,1 11
58 VTH ABL CD VHT Switching 0,1 11
59 YDEL Y Delay Time Control 0-15 77
60 NCOL No Color ID...

— 19 —
KV-25FS12 / 25FS12C
4-4. MB 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 
(TP-500 H. DRIVE) on the A Board.
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 TP-508 (V OUT) or CN501 pin 
6
(V DY+) and ground on the A Board .
4.  Check that V. Frequency shows 60...

— 20 —
KV-25FS12 / 25FS12C
V. CENTER ADJUSTMENT (VPOS)
Perform this adjustment after performing H. Frequency 
(Free Run) Check.
1.  Input a crosshatch signal.
2.  Activate the Service Adjustment Mode.
3.  Select the VPOS item with 
1
 and 4
 .
4.  Adjust value of VPOS with 
3
 and 6
 for the best vertical center.
5.  Press 
MUTING
 then ENTER
 to save into the memory.
H. CENTER ADJUSTMENT (HPOS)
Perform this adjustment after performing H. Frequency 
(Free Run) Check.
1.  Input a crosshatch signal.
2....