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FILE NO.


SERVICE MANUAL Colour Television Model No. PF2175
(Argentina)
Service Ref. No. PF2175-00




VIDEO L AUDIO R
MENU
CH
VOL



POWER




Specifications
Power Source . . . . . . . . .AC220V, 50Hz / 60Hz Product Code: 111376408
Receiving System . . . . . .PAL (M/M, N/N), NTSC (M/M)
Channel Coverage
Antenna mode VHF: CH02-CH13, UHF: CH14-CH69 Original Version
CATV mode VHF band: CH01-CH13, Mid band: CH14-CH22
Super band: CH23-CH36, Hyper band: CH37-CH64 Chassis Series: LA5-A
Ultra band: CH65-CH94 and CH100-CH125
Low mid band: CH95-CH99
Video IF . . . . . . . . . . . . .45.75MHz
Aerial Input Impedance . .75
Ext. Terminals Give complete "SERVICE REF. NO." for parts
Video input: Phono jack 2 (1Vp - p, 75) order or servicing. It is shown on the rating
Audio input: Phono jack (R/L) 2 (436mVrms, more than 40K) plate at the cabinet back of the unit.
Video monitor output: Phono jack 1(1Vp - p, 75)
Audio monitor output: Phono jack (L/R) 1(436mVrms, less than 600)
Headphone Jack: Mini stereo jack 1
This T.V. receiver will not work properly in
Sound Output (RMS) . . . . 3W + 3W
Speakers . . . . . . . . . . . . 5cm x 9cm x 2 pcs.
foreign countries where the television trans-
Dimensions . . . . . . . . . . 597(W) 484(H) 481(D)mm mission system and power source differ from
Weight . . . . . . . . . . . . . . approx. 21.8 Kg the design specifications. Refer to the specifi-
cation table.
Specifications subject to change without notice.


C7SJ
Contents
Safety Notice . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Chassis Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-4
IC Block Diagrams . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-7
Service Adjustments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-16
Purity and Convergence Adjustment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
Cabinet Parts List . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Chassis Electrical Parts List . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19-26




Safety Notice
SAFETY PRECAUTIONS

1: An isolation transformer should be connected in the 3: When replacing a chassis in the cabinet, always be
power line between the receiver and the AC line certain that all the protective devices are installed
when a service is performed on the primary of the properly, such as, control knobs, adjustment covers
converter transformer of the set. or shields, barriers, isolation resistor-capacitor net-
works etc.. Before returning any television to the
2: Comply with all caution and safety-related notes pro- customer, the service technician must be sure that
vided on the cabinet back, inside the cabinet, on the it is completely safe to operate without danger of
chassis or the picture tube. electrical shock.


X-RADIATION PRECAUTION

The primary source of X-RADIATION in television receiver is the picture tube. The picture tube is specially con-
structed to limit X-RADIATION emissions. For continued X-RADIATION protection, the replacement tube must be
the same type as the original including suffix letter. Excessive high voltage may produce potentially hazardous X
- RADIATION. To avoid such hazards, the high voltage must be maintained within specified limit. Refer to this ser-
vice manual, high voltage adjustment for specific high voltage limit. If high voltage exceeds specified limits, take
necessary corrective action. Carefully follow the instructions for + B1 volt power supply adjustment, and high volt-
age check to maintain the high voltage within the specified limits.



PRODUCT SAFETY NOTICE

Product safety should be considered when a component replacement is made in any area of a receiver.
Components indicated by mark in the parts list and the schematic diagram designate components in which
safety can be of special significance. It is particularly recommended that only parts designated on the parts list
in this manual be used for component replacement designated by mark . No deviations from resistance
wattage or voltage ratings may be made for replacement items designated by mark .




-2-
K1003 K1001 K1002
REAR MONITOR OUT REAR AV1-IN FRONT AV2-IN
VIDEO A-L A-R VIDEO A-L A-R VIDEO A-L A-R

VIDEO SW AV2
IC802 (AV1 or AV2) IN
2 SP902
MEMORY 7
5 6 AV1 IN IC1201
4
EXT. L-IN (AV2)




AUDIO MONITOR OUT-L
AUDIO MONITOR OUT-R




VIDEO MONITOR OUT
SDA SCL EXT. R-IN (AV2)




EXT. L-IN (AV1)
EXT. R-IN (AV1)
3 4 32 ON-TIMER 39 38 34 33 37 36
31 AUDIO RIGHT R
STANDBY IC3401 3 4 8 SP901
5/6
IC002
IC801 C-CAPTION IN
CXA2134QP LA42052-E
15 AUDIO LEFT 12
L
MTS DECODER/AUDIO CONTROL&SW 4 2
CPU 13
AUDIO AMP.
Chassis Block Diagrams
MAIN SIGNAL PROCESSING CIRCUIT




QXXAVC479P R
19
20
G
OSD
21
B
22
BLK




-3-
K1921
IIC BUS CONTROL HEADPHONE JACK
1
SDA
2 SCL




FM OUTPUT (TV AUDIO)
ANT EXT VIDEO IN




R
G
B
BLK




SCL
SDA
SELECTED VIDEO OUT
12 11 14 15 16 17 2 40 42
19 R
SAW IF IN IC201 Q901
TUNER 5/6 20 G
FILTER LA76818A B CRT
21
(WITH PLL) T611B IF/VIDEO/CHROMA/DEFLECTION
X161 23 27
A101 CONVERTER
TRANS T471 HV
Q432 FBT
HORIZ-OUT
VERT.OUT
HORIZ.OUT




12V(MAIN LOW)
9V REG.IC 5V-2
POWER 20V(AUDIO) DEFLECTION YOKE
AC IC202
CIRCUIT 130V(MAIN HIGH)
24V(VERT) REG.IC 5VRC
IC501
IC681 VERT-OUT
CPU OSC IN POWER ON/OFF OUT
6 31
OSC CPU OSC OUT (STANDBY=LOW)
LED
7
(RED)

IC002 SOUND MUTE OUT
29
SYSTEM CONTROL




AUDIO AMP. (ACTIVE=HIGH) IC3401 POWER CIRCUIT
MTS
RESET IN (RESET=LOW)
13 SDA
IC801 1 A101
2 SCL
KEY KEY SWITCH IN TUNER
12 CPU
SWITCH
QXXAVC479P
RC SIGNAL IN
28
Chassis Block Diagrams




RC PRE-AMP AFT S-CURVE IN
10 IC201
C-CAPTION IN
15 IF/VIDEO/CHROMA
RELAY ON/OFF OUT FOR DEGAUSSING OSD BLK OUT
23 22
(ON=HIGH) 19 OSD RED OUT
OSD GREEN OUT




-4-
20
21
OSD BLUE OUT
IC1201 VIDEO SW OUT
3 26 HORIZ. SYNC. IN
18
VIDEO SW (AV1=LOW, AV2=HIGH) DEFLECTION
VERT. SYNC. IN
17 CIRCUIT
ON-TIMER LED OUT 27
LED 32 3 4
(ON=LOW)
(GREEN)

POWER PROTECT IN




SCL



SDA
POWER CIRCUIT
(POWER ERROR=LOW) etc.
5 6


IC802
MEMORY
IC Block Diagrams
IC201 < IF/Video/Chroma/Def. > LA76818A




VOL




BPF
SW
DC




54
Audio Output SIF Input




DET



AMP



BPF
1




LIM
FM




SPLL
FM Output/Selected




53
SIF APC Filter

2
Audio Output




52
SIF Output




AGC
PIF AGC
3




IF
AGC
RF




51
RF AGC Output Ext. Audio Input
4




VIDEO




VIDEO




50
TRAP
PIF Input1 APC Filter




AMP
5




DET
VIF




49
PIF Input 2 VCO Coil 1
6




A2C
PLL



48
IF Ground VCO Coil 2
7
VCC 5V




47
IF Vcc VCO Filter
IF
8




IDENT
AFT




46
IF
FM Filter Video Output
9




45
10




AFT Output Black Level Detector
PEAKING




DELAY




VIDEO
CORING




TRAP
LINE




CLMP
SW




44
Internal Video Input (S-C IN)
11




Bus Data
BUS




V/C VCC
43
12




Video/Vertical Vcc


5V
Bus Clock
STRETCH




SYNC
BLACK

SEP




SW




CLMP
ABL




42
13




ABL External Video Input(Y-IN)
ON/OFF
REST




ACC



BPF
DC




41
Video/Vertical/BUS Ground
14




Red Input
CONTRAST




APC1
BRIGHT
CLAMP




OSD




40
15




Green Input Selected Video Output
VXO
DEMO




39
16




Blue Input Chroma APC1 Filter
TINT
PAL
SW




DDS




38
17




Fast Blanking Input 4.43 MHz Crystal
CONTRAST
BRIGHT




CLAMP




APC2
VCO
18




37




RGB Vcc Clamp Filter
VCC




36




Chroma APC2 Filter
19




Red Output
DRIVE/OUT-OFF




MATRIX
OSD


RGB




SECAM R-Y Input
SW




35
20




Green Output
CLAMP
DC ADS.




(Cr Input)
SW




SECAM B-Y Input
34
21




Blue Output
(Cb Input)
SYNC SW




fsc output or C
FSC/




33




CCD/Horizontal Ground
22




Sync output
1H DELAY
COLOR
CLAMP




32
23




Vertical Output CCD Filter
+
RAMP



VER


VER
SEP
VER

C/D




31




Ramp ALC Filter
24




CCD Vcc
ALC
LPF




VCC
1H
HOR
VCC




30
25




Horizontal/BUS Vcc Clock (4MHz) Outupt
VCC
H




1/256
AFC1


HOR




HOR
VCO
C/D




29
26




Horizontal AFC Filter VCO IREF
SHIFTER
PHASE


AFC2
HOR
OUT




FBP


28
27




Horizontal Output Flyback Pulse Input




-5-
1K
SIF
Data Clock APC 1000p
10p Filter 0.01u
SIF.Out SIF.In
11 12 52 54 53
500K LIM FM Gain Deem-TC
BUS Det AMP 1bit 1bit
to BUS Line Snd Sound 500K FM
Interface Det Amp
BPF BPF Det FM
Amp + De- Out
Amp emph 2
SIF -
IC Block Diagrams




VCO FM.Level
5bit
0.01u




SIF. Sys pre-
PIF VIF AMP 2bit scaller + 9
In1 APC - +
5 2.5V FM Mute FM
IF In
1u




OSC Det Chroma Filter
SAW VIF 1 VIF 2 VIF 3 1 bit
C/D C/D
6 Video
PIF Det Video
In2 Sound Out
Amp 46
Trap
IF To Audio in
IF AGC B/N +
9V Video.Level Ident BUS 51
Drive INV
IC201 LA76818A




10u
3bit
Input VOLUME




30K
Select (ATT) 1 Audio.out
RF 2ndIF IF
RF AGC 4




-6-
Out + AGC AGC AGC
A.SW VOLUME A.Fil.Def
Chroma 1bit




120K
1bit Filter
RF AGC VCO
Delay
6bit A.MUTE VOLUME VOLUME
Buzz D/A 7bit
Canceller 1bit
IF AGC
Def Lock 47
IF VCC 1bit -/4 Det + VCO
8 VIF VCO VCO Filter
+
Counter Ident
0.47u




Alignment
+/4
+ To To Phase
BUS Reset VIF.Sys
- BUS Pulse Detector
2bit
IF (6 Vcc)/7 Vcc
GND VIF Chroma
7 APC VCO Counter
100K




Det AFT
PLL Pull-in SW AFT 10
0.1u




3 50 48 49