LG L316 Service manual

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A AC :Alternating Current

ACC :Automatic Color Control ACSS :Automatic Channel Setting System ADJ :Adjust A/E :Audio Erase AFC :Automatic Frequency Control AFT :Automatic Fine Tuning AGC :Automatic Gain Control A.H.SW :Audio Head Switch ALC :Automatic Level Control AM :Amplitude Modulation AMP :Amplifier ANT :Antenna APC :Automatic Phase Control ASS’Y :Assembly AUX :Auxiliary

B B :Base

BGP :Burst Gate Pulse BPF :Bandpass Filter BS :Brodcasting Satellite BW or B/W :Black and White

C C :Capacitor, Chroma, Collector

CAN :Cancel CAP :Capstan CAP.BRK :Capstan Brake CAP.RVS :Capstan Reverse CATV :Cable Television CBA :Circuit Board Assembly CCD :Charge Coupled Device C.CTL :Chro Control, Capstan Control CFG :Capstan Frequency Generator CHROMA :Chrominance CNR :Chroma Noise Redution COMB :Combination

Comb Filter

COMP :Comparator

Composite

Compensation CONV :Converter C.ROT SW :Color Rotary Switch CS :Chip Selcet C.SYNC :Composite Synchronization CTL DIV :Control Divide CUR :Current CYL :Cylinder

D D :Drum, Digital, Diode, Drain

D.ADJ :Drum Adjust DC :Direct Current D.CTL :Drum Control DEMOD :Demodulator DET :Detector DEV :Deviation DHP :Double High Pass DIGITRON :Digital Display Tube DL :Delay line DOC :Drop Out Compensator DUB :Dubbing D.V SYNC :Dummy Vertical Synchronization

E E :Emitter

EE :Electric to Eletric EMPH :Emphasis ENA :Enable ENV :Envelope EP :Extended Play EQ :Equalizer EXP :Expander

F F :Fuse

FB :Feed Back FBC :Feed Back Clamp FE :Full Erase FG :Frequency Generator FL :Filter FM :Frequency Modulation F/R :Front/Rear FS :Frequency Synthesizer FSC :Subcarrier Frequency F/V :Frequency Voltage

G GEN :Generator H H :High, Horizontal I IC :Integrated Circuit

IF :Intermediate Frequency INS :Insert

L L :Low, Left, Coil

LD :LED LD VTG CTL

:Loading Voltage Control LECHA :Letter Character L.M :Level Meter LP :Long Play

LPF :Low Pass Filter

M MAX :Maximum

MD :Modulator MECHA.CTL

:Mechanism Control MIC :Microphone MIN :Minimum MIX :Mixer, Mixing M.M. :Monostable, Multivibrator MMV :Mono Multi Vibrator MOD :Modulation, Modulator MODEM :Modulator-Demodulator MPX :Multiplex

N NR :Noise Reduction

O OSC :Oscillator

OSD :On Screen Display

P PB :Playback

PCB :Printed Circuit Board P.CTL :Power Control PRE-AMP :Preamplifier P.F :Power Failure PG :Pulse Generator PLL :Phase Locked Loop PREM.DET :Premire Detect P.P :Peak-to-Peak PS :Phase Shift PWM :Pulse Width Modulation PWR CTL :Power Control

Q Q :Transistor

QH :Quasi Horizontal QSR :Quick Setting Record QTR :Quick Timer Record QV :Quasi Vertical

R R :Resistor, Right

RE(or RC) :Remocon, Receiver REC :Recording REC S ‘H’ :Record Start ‘Hight’ REF :Reference REG :Regulated, Regulator REMOCON :Remote Control(unit) RF :Radio Frequency R/P :Record/Playback RTC :Reel Time Counter

S S :Serial

S.ACCEL :Slow Accel SAOP :Second Audio Program SC :Scart, Simulcast S.DET :Secam Detect SH :Shift SHARP :Sharpness SIF :Sound Intermediate Frequency SLD :Side Locking S/N :Signal to Noise Ratio SP :Standard Play ST :Stereo SUB :Subtract, Subcarrier SW or S/W :Switch SYNC :Synchronization SYSCON :System Control

T T :Coil

TP :Test Point TR :Transistor TRK :Tracking TRANS :Transformer TU :Tuner, Take-up

U UHF :Ultra High Frequency

UNREG :Unregulated

V V :Volt, Vertical

VA :Always Voltage VCO :Voltage Controlled Oscillator VGC :Voltage Gain Control VHF :Very High Frequency V.H.SW :Video Head Switch VISS :VHS Index Search VPS :Video Program System VR :Variable Resistor or Volume V-SYNC :Vertical Synchronization VTG :Voltage VV :Voltage to Voltage VXO :Voltage X-tal Oscillator

W W :Watt

WHT :White W/O :With out

X X-TAL :Crystal Y Y/C :Luminance/Chrominance

YNR :Luminance Noise Reduction

Z ZD :Zener Diode

SECTION1 SUMMARY

KEY TO ABBREVIATIONS

LG L316

1-3

Prior to shipment from the factory, the products are strictly inspected to confrom with the recognized product safety and electrical codes of the countries in which they are to be sold. However, in order to maintain such compliance, it is equally important to implement the following precautions when a set is being serviced.

• Precautions during Servicing

1. Locations requiring special caution are denoted by labels and inscriptions on the cabinet, chassis and certain parts of the product. When performing service, be sure to read and comply with these and other cautionary notices appearing in the operation and service manuals.

2. Parts identified by the symbol and shaded (

) parts are critical for safety. Replace only with specified part numbers. Note : Parts in this category also include those specified to comply with X-ray emission standards for

products using cathode ray tubes and those specified for compliance with various regulations regarding spurious radiation emission.

3. Use Specified internal wiring. Note especially:

1) Double insulated wires

2) High voltage leads

4. Use specified insulating materials for hazardous live parts. Note especially:

1) Insulation Tape

2) PVC tubing

3) Spacers

4) Insulation sheets for transistor

5. Observe that wires do not contact heat producing parts (heatsinks, oxide metal film resistors, fusible resistors, etc.)

6. Check that replaced wires do not contact sharp edged or pointed parts.

7. 1) When a power cord has been replaced, check

that A mark is made on the cord, under strain, near the aperture, and the flexible cord is subjected 100 times to a pull of 40N for a duration of 1 second each.

2) During the test, the cord shall not be displaced by

more than 2mm

8. Also check areas surrounding repaired locations.

9. The internal wiring is secured so as not to approach the heating parts and high voltage parts by its shape. So, these wires must be restored to its former state.

IMPORTANT SAFETY PRECAUTIONS

Fig. 1

Power code

1-4

Fig. 3

SAFETY CHECK AFTER SERVICING

Examine the area surrounding the repaired location for damage or deterioration. Observe that screws, parts and wires have been returned to original positions. Afterwards, perform the following tests and confirm the specified values in order to verify compliance with safety standards.

• Insulation resistance test

confirm the specified insulation resistance or greater between power cord plug prongs and externally exposed parts of the set (RF terminals, antenna terminals, video and audio input and output terminals, incrophone jacks, earphone jacks, etc.) See table below.

• Dielectric strength test

Confirm specified dielectric strength or greater between power cord prongs and exposed accessible parts of the set (RF terminals, antenna terminals, video and audio input and output terminals, incrophone jacks, earphone jacks, etc.) See table below.

• Clearance distance

When replacing primary circuit components, confirm specified clearance distance (d), (d') between soldered terminals, and between terminals and surrounding metallic parts. See table below.

Table 1 : Ratings for selected areas

* Class II model only.

Note. This table is unofficial and for reference only. Be sure to confirm the precise values for your particular

country and locality.

• Leakage Current test

Confirm specified or lower leakage current between B(earth ground, power cord plug prongs) and externally exposed accessible parts (RF terminals, antenna terminals, video and audio input and output terminals, microphone jacks, earphone jacks, etc.)

Measuring Method: (Power ON) Insert load Z between B(earth ground, power cord plug prongs) and exposed accessible parts. Use an AC voltmeter to measure across both terminals of load Z. See figure and following table.

Table 2:Leakage current ratings for selected areas.

Note. This table is for IEC member only. Be sure to confirm the precise values for your particular country and

Note. locality.

Chassis

Primary circuit terminals

Fig. 2

AC Line Voltage

100 to 130 V

200 to 240 V

*100 to 130 V

*200 to 240 V

Europe

Australia

Europe

Australia

Other terminals

Antenna earth

terminals

E 0.7m A peak

i E 2m A DC i E 0.7m A peak

i E 2m A DC

F 10 MΩ/500 V DC

4kV 1 minute

F 6mm(d) F 8mm(d)

(a Power cord)

Region

Load Z Leakage Current(i)

Earth Ground

(B) to :

Region

Insulation

Resistance

Dielectric

Strength

Clearance

Distance(d),(d)

Ω

50k

Ω

Exposed accessible part

Load

Earth Ground, Power cord plug prongs

AC Voltmeter

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In case that defective EEPROM of PAL models is replaced, to operate these sets from the initial state MP KEY must be repaired as well before delivering to the customer. If MP KEY isn’t repaired the setting of RF OUT channel or LANGUAGE might be different from that for custormer’s country.

•MP KEY : In case of PAL VCR if holding the REC button on the front panel and the CLEAR button on the

remote control handset for 5 ~ 7 seconds with power being switch all and no tapes, OK is displayed at FLD for FLD models and LED becomes on for LED CLOCK models. This is the state that initializing EEPROM is finished. (In case of PAL VCP if holding the REC button on the front panel and the MENU button on the remote control handset for 5 ~ 7 seconds with power being off and no tapes, All the LED DOTs become on. This is the state that initializing EEPROM is finished.)

•MP KEY's function : MP KEY sets EEPROM's data up to the initial state.

SERVICE NOTICE ON REPLACING EEPROM

TIMER

REC

VCR

• FLD MODEL:

MP KEY “OK”

• LED CLOCK MODEL:

MP KEY Switch all on a Light

• LED DOT MODEL:

MP KEY Switch all on a Light

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PREDICTED ERRORS OF MODULATOR & HOW TO COPE WITH THEM

CONTENT

Handle RF OUT CH by each region

For G : 30 ~ 40 ch For I : 30 ~ 40 ch

30 ~ 40 ch

For G/K : 30 ~ 40 ch (G-initial for Australia)

30 ~ 40 ch (K-initial for CIS) 30 ~ 40 ch (G-initial for Southeast asia)

PREDICTED ERRORS

1. In RF Inteference, it is impossible to control from the outside.

2. After forwarding models with G/K system for G/K, it is difficult to change system.

HOW TO HANDLE

1. To subdivide CH according to model and region.

2. To adjust CH or System after open the top case.

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SPECIFICATIONS

General

Power.................................... AC110~240V, 50/60Hz

Power consumption .............. Approx. 10 Watts

Dimensions (W x H x D) ....... 360 x 94 x 230 mm

Weight................................... Approx. 3.0 Kg.

Operating temperature.......... 5 ~ 35°C

Operating humidity................ Less than 80%

Video

Television system.................. CCIR standard (625 lines, 50 fields), PAL/SECAM colour signal

Recording format .................. PAL/MESECAM/NTSC3.58/NTSC4.43

RF OUT................................. PAL/SECAM(G or K)

Input level.............................. 1.0Vp-p, 75 Ohm, unbalanced

Output level .......................... 1.0Vp-p, 75 Ohm, unbalanced

RF modulator ........................ UHF channels 32~40 (adjustable)

Audio

Input level.............................. -6 dBm, more than 47 kOhms

Output level........................... -6 dBm, less than 1.5 kOhms

Audio track ........................... Mono track

Audio frequency response .... 100 Hz ~ 10kHz(-6/+3 dBm)

• Design and specifications are subject to change without notice.

2-1

SECTION2 CABINET & MAIN FRAME

Fig.2-1

SERVICE METHOD

(1) Disassembly Flow

(Positioned Upside Down)

(2) Re-assembly Flow for service like Fig. 2-1

(3) To check and replace Electrical parts

1 Disassemble the unit according to

No.1) Disassembly Flow.

2 Re-assemble the unit according to

No.2) Re-assembly Flow.

3 Place the unit like Fig. 2-1 4 Check and replace Electrical parts.

NOTE :

1 Insert Video Cassette Tape inversely like Fig. 2-1

to check and replace defective parts.

2 In disassembling and reassembling, be careful not

to damaged CST switch.

Top Case

Bottom Cover

Front Panel

Housing & Deck

Assembly

Main C.B.A

LED C.B.A

Main C.B.A

Housing & Deck

Assembly

Housing y Mecanismo

Cassette Tape

(Upside Down)

C.B.A Princioal

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EXPLODED VIEWS

1. Cabinet and Main Frame Section

283

280

284

261

260

457

A00

464

462

250

300

A43

330

452

457

320

A46

A42

A49

BCD

NOTE) Refer to “SECTION 5 REPLACEMENT

PARTS LIST” in order to look for the part number of each part. _ OPTIONAL PARTS

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2. Packing Accessory Section

• Packing Accessory Section Part List

801

808

INSTRUCTION ASS'Y

BATTERY

810

CABLE SET ASS'Y

803

PACKING ASS'Y

804

SHEET CUSHION

802

BOX CARTON

(Optional Parts)

900

REMOCON

3-13-1

Hi-Fi

AVCP

U-COM

P S

SYSTEM

A/V

DECK CNT.

A/V JACK

M O D U

T O R

MODULATOR

SMPS

DISP

KEY

BOARD(L)

KEY

BOARD(R)

: Measurement point : Adjustment point

SECTION 3 ELECTRICAL

ELECTRICAL ADJUSTMENT POINTS ARRANGEMENT

3-23-2

Fig. 3-2

ELECTRICAL ADJUSTMENT PROCEDURES

1. Servo Adjustment

1) PG Adjustment

• Test Equipment

• Adjustment And Specification

a) OSCILLOSCOPE

b) PAL TEST TAPE (VHS SP)

MODE

SP TAPE PLAY

• Adjustment Procedure and Caution

a) Insert the PAL SP Test Tape and play.

Note - Adjust the distance of X, pressing SET REC KEY and “OK” on RCU simultaneously. (3SEC

HOLD). In ININTIAL MODE, LED of POWER/CST IN/LP/EP/STANDBY is on .(TRK PRESET MODE)

b) In TRK PRESET MODE,Pressing SET REC KEY and “OK” on RCU same, and then PG is adjusted

automatically. (LED of PLAY/REC is off.) c) Connect the CH1 of the oscilloscope to the H/SW(W373, W374) and CH2 to the Video Out for the VCR. d) Trigger the mixed Video Signal of CH2 to the CH1 H/SW(W373, W374), and then check the distance

(time difference), which is from the selected A(B) Head point of the H/SW(W373, W374) signal to the

starting point of the vertical synchronized signal, to 416 µsec ± 32 µsec.

• WAVEFORM

• CONNECTION

V.Out Jack

H/SW(W373, W374)

AUTO

PAL PG : 416 ± 32usec NTSC : 412 ± 32usec

MEASUREMENT POINT ADJUSTMENT POINT SPECIFICATION

t=416 µ sec ± 32 µ sec

VIDEO

OUT

CH-1 CH-2

W373/W374

+ 25 hidden pages