SAFETY PRECAUTIONS IMPORTANT SAFETY NOTICE The parts identified by many electrical and mechanical parts in this chassis have special safety-related characteristics. in the Schematic Diagram and Replacement Parts List. It is essential that these special safety parts be replaced with the same components as recommended in this manual to prevent X-RADIATION, Shock, Fire, or other Hazards.
SERVICING PRECAUTIONS CAUTION: Before servicing receivers covered by this service manual and its supplements, please read and follow the SAFETY PRECAUTIONS. NOTE: If unforeseen circumstances create conflict between the following servicing precautions and any of the safety precautions, always follow the safety precautions. Remember: Safety First.
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8. Always connect the test receiver ground lead to the receiver chassis ground before connecting the test receiver positive lead. Always remove the test receiver ground lead last. 9. Use with this receiver only for the test fixtures specified in this service manual. CAUTION: Do not connect the test fixture ground strap to any heat sink in this receiver.
Electrostatically Sensitive (ES) Devices Some semiconductor (solid state) devices can be damaged easily by static electricity. Such components are usually called Electrostatically Sensitive (ES) Devices. Examples of typical ES devices are integrated circuits and some field effect transistors and semiconductor “chip” components. The following techniques should be used to help reduce the incidence of component damage caused by static electricity.
General Soldering Guidelines 1. Use a grounded-tip, low-wattage soldering iron and appropriate tip size and shape that will maintain tip temperature within the range of 500 F to 600 2. Use an appropriate gauge of RMA resin-core solder composed of 60 parts tin/40 parts lead.
“Small-Signal” Discrete transistor Removal/Replacement • Remove the defective transistor by clipping its leads as close as possible to the component body. • Bend into a “U” shape the end of each of three leads remaining on the circuit board. • Bend into a “U”...
Circuit Board Foil Repair Excessive heat applied to the copper foil of any printed circuit board will weaken the adhesive that bonds the foil to the circuit board causing the foil to depart from or “lift-off” the board. The following guidelines and procedures should be followed whenever this condition is encountered.
PRODUCT FUNCTIONS FUNCTIONS TYPE TN131AUV LA76814 OTHER Type of power plug √ Tube V-CHIP CCD Color system NTSC Broadcast system No. Of preset channels CATV band width Blue/black screen Menu OSD √ OSD language English/French/ Spanish Manifold PIC modes √ Program preview Y/C separation circuit Denoise circuit...
Audio output power (w) Super woofer NO of built-in speakers Analog surround stereo Treble/bass lifting and balancing Multiple audio mode AV stereo Digital reverberation Tone control Auto volume leveling Mute 3D surround sound MAX volume preset 5 bands equalizer NICAM AV in Flank 1: Rear 1 AV out...
Alignment and Adjustments 1. Please read and remember the contents of the user’s manual and the warnings on the back cover of the TV set carefully before using the machine especially the safety instructions. 2. Keep the set away from heaters, ovens or such heating equipment. 3.
d. AV input check: press AV/TV button, screen will display AV mode or TV mode and audio input signal can be observed, picture and sound must be normal. Stereo adjustment: Receive stereo signal (recommended audio: L 300Hz, R 3KHz). Connect two inputs of double trace oscillograph into XS601, XS602 Note: Do not make XS601, XS602 outputs short.
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AGC ALIGNMENT: Receive a color bar signal, 60dB, NTSC M color bar pattern, and check if there is noise in the picture, if there is some noise, press FACTORY button and enter service mode, adjust RF.AGC value and make the noise just disappear, press FACTORY button and exit service mode.
2. Setting item explanation: Function LA76814/LA768 1:select 0: select LA76814 LA76812 SAP IC SELECT 0:TDA9850; 1:CXA2104; 2:TDA9855; 3:UPC1815B SUB.CONT Sub-contrast (0-31) SUB.COLOR Sub-color (0-63) SUB.SHARP Sub-sharpness (0-31) SUB.TINT Sub-tint (0-63) BLK.STR.DEF Black level stretch (0:on; 1:off) AFC GAIN AFC gain (0:low; 1:high) V.SEPUP Vertical synchronize sensitive 0 low;...
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AV OPTION 0 without AV 1 one AV input 2 two AV input 3 three AV input POSITION L/R 1 logo display on right top of 0 logo display on left top of screen screen 1 blue background without BLUE BACK 0 No blue background without signal signal BLACK BACK...
IC reference data: 1. N701 (LC86F3232A) Voltage Function Voltage V Function R-input 0.06 Connect to 5V resistor 5.03 G-input 0.06 via a Connect to 5V resistor 5.03 B-input 0.07 via a Connect to 5V 5.04 Blank 0.15 resistor via a Connect to 5V 5.03 n.c.
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2. N101 LA76814K Voltage Voltage Function Function Audio output 2.23 FBT input 1.06 FM output 2.23 I reference 1.69 IF AGC filter 2.22 Clock output 0.002 RF AGC 2.59 0.002 n.c. PIF AMP input 1.30 OSD gain control 3.05 PIF AMP input 2.83 IF ground 2.83...