SERVICE MANUAL This Service Manual is for the LH850-M32 (A0CF2EP) model. For the LH850-M32 (A0CF2EP) model, the letter (A0CF2EP) is printed on the Serial Number Label on the back of the unit. Refer to the Serial Number Label below. Serial No. Label "A0CF2EP"...
IMPORTANT SAFETY PRECAUTIONS Prior to shipment from the factory, our products are strictly inspected for 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.
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4. Hot Chassis Warning - 7. Product Safety Notice - Some electrical and mechanical parts have special safety-related a. Some TV receiver chassis are electrically characteristics which are often not evident from connected directly to one conductor of the AC visual inspection, nor can the protection they give power cord and maybe safety-serviced without necessarily be obtained by replacing them with...
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Precautions during Servicing A. Parts identified by the ! symbol are critical for safety. Replace only with part number specified. B. In addition to safety, other parts and assemblies are specified for conformance with regulations applying to spurious radiation. These must also be replaced only with specified replacements.
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Safety Check after Servicing Examine the area surrounding the repaired location Chassis or Secondary Conductor for damage or deterioration. Observe that screws, parts and wires have been returned to original posi- tions. Afterwards, perform the following tests and con- Primary Circuit firm the specified values in order to verify compliance with safety standards.
STANDARD NOTES FOR SERVICING Circuit Board Indications How to Remove / Install Flat Pack-IC 1. The output pin of the 3 pin Regulator ICs is 1. Removal indicated as shown. With Hot-Air Flat Pack-IC Desoldering Machine: 1. Prepare the hot-air flat pack-IC desoldering Top View Bottom View machine, then apply hot air to the Flat Pack-IC...
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With Soldering Iron: With Iron Wire: 1. Using desoldering braid, remove the solder from 1. Using desoldering braid, remove the solder from all pins of the flat pack-IC. When you use solder all pins of the flat pack-IC. When you use solder flux which is applied to all pins of the flat pack-IC, flux which is applied to all pins of the flat pack-IC, you can remove it easily.
2. Installation Instructions for Handling Semi- 1. Using desoldering braid, remove the solder from conductors the foil of each pin of the flat pack-IC on the CBA Electrostatic breakdown of the semi-conductors may so you can install a replacement flat pack-IC more occur due to a potential difference caused by easily.
CABINET DISASSEMBLY INSTRUCTIONS 1. Disassembly Flowchart Removal Step/ Remove/*Unhook/ This flowchart indicates the disassembly steps for the Loc. Part Fig. Unlock/Release/ cabinet parts, and the CBA in order to gain access to Note Unplug/Unclamp/ item(s) to be serviced. When reassembling, follow the Desolder steps in reverse order.
ELECTRICAL ADJUSTMENT INSTRUCTIONS General Note: “CBA” is abbreviation for How to set up the service mode: “Circuit Board Assembly.” Service mode: Note: Electrical adjustments are required after 1. Turn the power on. replacing circuit components and certain mechanical parts. It is important to perform 2.
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1. Purity Check Mode 2. VCOM Adjustment This mode cycles through full-screen displays of red, Test Point Adj. Point green, blue, and white to check for non-active pixels. 1. Enter the Service mode. Screen buttons 2. Each time pressing [7] button on the remote M.
The White Balance Adjustment should be 5. [CUTOFF] Press [1] button to select “COR” for Red Cutoff performed when replacing the LCD Panel adjustment. Press [3] button to select “COB” for or Digital Main CBA. Blue Cutoff adjustment. [DRIVE] 3. White Balance Adjustment Press [4] button to select “DR”...
HOW TO INITIALIZE THE LCD TELEVISION How to initialize the LCD television: 1. Turn the power on. 2. Enter the service mode. (Refer to page 5-1.) - To cancel the service mode, press [ ] button on the remote control unit. 3.
FIRMWARE RENEWAL MODE Equipment Required [Update procedure] 1. Plug in the AC power cord. a. USB storage device 2. Press [ ] button on the remote control unit to turn b. Remote Control Unit off (standby). 3. Check “STAND BY” indicator (Red LED) lighting. Firmware Update Procedure 4.
TROUBLESHOOTING FLOW CHART NO.1 The power cannot be turned on. See FLOW CHART No.2 <The fuse blows out.> Is the fuse (F601) normal? Check if there is any leak or short-circuiting on the primary circuit component, and service it if defective. (IC607, Q601, Q602, D609, D610, D611, D612, T601, T602, R601) Is 32V voltage supplied to the cathode of D514?
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FLOW CHART NO.5 INV+16V is not output. Check D504, D505, C503 and their periphery circuit, and service it defective. Check Q504, Q505, D506, D507, P-ON-H1 line and their periphery circuit, and service it defective. FLOW CHART NO.6 AL+3.3V is not output. Is approximately 6V voltage supplied to the collector Check D525, C516 and their periphery circuit, and of Q521?
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FLOW CHART NO.8 LCD+24V is not output. Is approximately 32V voltage supplied to the cathode of D514? Is approximately 32V voltage outputted to the collector of Q504? Is approximately 24V voltage supplied to the emitter of Q405? Check Q404, Q405 and their periphery circuit, and service it if defective.
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FLOW CHART NO.11 The key operation is not functioning. Re-install the switches (SW101, SW103-SW107) correctly or replace the poor switch. Check the switches (SW101, SW103-SW107) and their periphery, and service it if defective. Replace Digital Main CBA Unit. FLOW CHART NO.12 No operation is possible from the remote control unit.
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FLOW CHART NO.14 No operation is possible from the remote control unit. Check AL+3.3V line and service it if defective. Replace the RS102 (remote control receiver) or remote control unit. Check the line between Pin(1) of RS102 (remote control receiver) and Pin(13) of CN403, and service it if defective.
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FLOW CHART NO.16 Picture does not appear normally. Check the line between Pin(16, 18) of CN403 and Are the DIF signals outputted to Pin(16, 18) of CN403? Pin(4, 5) of TU1, and TU1(Tuner Unit), and service it if defective. Replace Digital Main CBA Unit or LCD Module Assembly.
SCHEMATIC DIAGRAMS / CBA AND TEST POINTS Standard Notes WARNING Many electrical and mechanical parts in this chassis have special characteristics. These characteristics often pass unnoticed and the protection afforded by them cannot necessarily be obtained by using replacement components rated for higher voltage, wattage, etc.
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LIST OF CAUTION, NOTES, AND SYMBOLS USED IN THE SCHEMATIC DIAGRAMS ON THE FOLLOWING PAGES: 1. CAUTION: FOR CONTINUED PROTECTION AGAINST FIRE HAZARD, REPLACE ONLY WITH THE SAME TYPE FUSE. 2. CAUTION: Fixed Voltage (or Auto voltage selectable) power supply circuit is used in this unit. If Main Fuse (F601) is blown, first check to see that all components in the power supply circuit are not defective before you connect the AC plug to the AC power supply.
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Power Supply 1 & Power SW Schematic Diagram CAUTION ! NOTE: CAUTION ! Fixed voltage (or Auto voltage selectable) power supply circuit is used in this unit. The voltage for parts in hot circuit is measured using For continued protection against fire hazard, If Main Fuse (F601) is blown , check to see that all components in the power supply hot GND as a common terminal.
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Power Supply 2 Schematic Diagram 10-4 A0CF2SCP2...
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Power Supply 3 Schematic Diagram 10-5 A0CF2SCP3...
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Inverter Schematic Diagram NOTE: The voltage for parts in hot circuit is measured using hot GND as a common terminal. 10-6 A0CF2INV...
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Function & IR Sensor Schematic Diagram 10-7 A0CF2SCF...
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Digital Main 1 Schematic Diagram 1 NOTE: The order of pins shown in this diagram is different from that of actual IC3301. IC3301 is divided into six and shown as IC3301 (1/7) ~ IC3301 (7/7) in this Digital Main Schematic Diagram Section. 10-8 A0CF2SCD1...
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Digital Main 2 Schematic Diagram 1 NOTE: The order of pins shown in this diagram is different from that of actual IC3301. IC3301 is divided into six and shown as IC3301 (1/7) ~ IC3301 (7/7) in this Digital Main Schematic Diagram Section. 10-9 A0CF2SCD2...
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Digital Main 3 Schematic Diagram 1 NOTE: The order of pins shown in this diagram is different from that of actual IC3301. IC3301 is divided into six and shown as IC3301 (1/7) ~ IC3301 (7/7) in this Digital Main Schematic Diagram Section. 10-10 A0CF2SCD3...
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Digital Main 4 Schematic Diagram 1 NOTE: The order of pins shown in this diagram is different from that of actual IC3301. IC3301 is divided into six and shown as IC3301 (1/7) ~ IC3301 (7/7) in this Digital Main Schematic Diagram Section. 10-11 A0CF2SCD4...
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Digital Main 5 Schematic Diagram 1 NOTE: The order of pins shown in this diagram is different from that of actual IC3301. IC3301 is divided into six and shown as IC3301 (1/7) ~ IC3301 (7/7) in this Digital Main Schematic Diagram Section. 10-12 A0CF2SCD5...
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Digital Main 6 Schematic Diagram 1 NOTE: The order of pins shown in this diagram is different from that of actual IC3301. IC3301 is divided into six and shown as IC3301 (1/7) ~ IC3301 (7/7) in this Digital Main Schematic Diagram Section. 10-13 A0CF2SCD6...
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Digital Main 7 Schematic Diagram 1 NOTE: The order of pins shown in this diagram is different from that of actual IC3301. IC3301 is divided into six and shown as IC3301 (1/7) ~ IC3301 (7/7) in this Digital Main Schematic Diagram Section. 10-14 A0CF2SCD7...
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Power Supply CBA Top View Because a hot chassis ground is present in the power supply NOTE: CAUTION ! circuit, an isolation transformer must be used when repairing. The voltage for parts in hot circuit is measured using Fixed voltage (or Auto voltage selectable) power supply circuit is used in this unit. Also, in order to have the ability to increase the input slowly, hot GND as a common terminal.
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Power Supply CBA Bottom View Because a hot chassis ground is present in the power supply NOTE: CAUTION ! circuit, an isolation transformer must be used when repairing. The voltage for parts in hot circuit is measured using Fixed voltage (or Auto voltage selectable) power supply circuit is used in this unit. Also, in order to have the ability to increase the input slowly, hot GND as a common terminal.
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Inverter CBA, Function CBA, IR Sensor CBA & Power SW CBA Top View NOTE: The voltage for parts in hot circuit is measured using hot GND as a common terminal. Function CBA Power SW CBA IR Sensor CBA Not use Inverter CBA 10-17 BA0CF0F01021...
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Inverter CBA, Function CBA, IR Sensor CBA & Power SW CBA Bottom View NOTE: The voltage for parts in hot circuit is measured using hot GND as a common terminal. Function CBA Not use IR Sensor CBA Power SW CBA Inverter CBA 10-18 BA0CF0F01021...
WAVEFORMS WF1 ~ WF6 = Waveforms to be observed at Waveform check points. (Shown in Schematic Diagram.) Input: PAL Color Bar Signal (with 1kHz Audio Signal) Pin 2 of CN404 Pin 4 of CN404 VIDEO-Y VIDEO-Y 0.2V 0.2V 20µs 20µs VIDEO VIDEO 0.2V...
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WF7 ~ WF10 = Waveforms to be observed at Waveform check points. (Shown in Schematic Diagram.) Input: PAL Color Bar Signal (with 1kHz Audio Signal) Pin 22 of CN401 Pin 26 of CN404 WF10 AUDIO(L) AUDIO(L) 0.5V 0.5V 0.5m 0.5ms VIDEO-R VIDEO-R 0.5V...
EXPLODED VIEWS Cabinet Inverter CBA CL802 CL600 SP802 Function CBA CL103A IR Sensor CBA CL801 Power SW CBA CL1003 SP801 AC701 LCD1 Power Supply CBA CL3901 See Electrical Parts List CL401 for parts with this mark. CL404 CL403 Stand Assembly CL402 Digital Main CBA Unit X3301...
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Packing Stand Assembly Some Ref. Numbers are not in sequence. X2-1 X2-2 Tape Packing Tape Tape Packing Tape 13-2 A0CF0PEX...
MECHANICAL PARTS LIST PRODUCT SAFETY NOTE: Products marked with a Ref. No. Description Part No. ! have special characteristics important to safety. RATING LABEL A0CF2EP ---------- Before replacing any of these components, read CLOTH(B) L5201U0 15X10X1.0T 0EM400076 carefully the product safety notice in this service SCREW P-TIGHT M4X14 BIND HEAD+BLK GBHP4140 manual.
ELECTRICAL PARTS LIST PRODUCT SAFETY NOTE: Products marked with a Ref. No. Description Part No. ! have special characteristics important to safety. C207 CHIP CERAMIC CAP . CH J 330pF/50V or CHD1JJ3CH331 Before replacing any of these components, read CAP CHIP 1608 J/C0G/330pF/50V CHD331EYA030 carefully the product safety notice in this service C208...
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Ref. No. Description Part No. Ref. No. Description Part No. CAP CHIP 1608 Z/Y5V/0.1µF/50V CHD104EYA036 CAP ELE 1000µF/10V/M/85 or CEB102KSN001 C406 CHIP CERAMIC CAP .(1608) F Z 0.1µF/50V or CHD1JZ30F104 CAP ELE 1000µF/10V/M/85 CEB102TEP001 CAP CHIP 1608 Z/Y5V/0.1µF/50V CHD104EYA036 C518 CHIP CERAMIC CAP .(1608) B K 0.1µF/50V or CHD1JK30B104 C407...
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Ref. No. Description Part No. Ref. No. Description Part No. C801 CHIP CERAMIC CAP .(1608) B K 0.047µF/50V or CHD1JK30B473 CONNECTORS CAP CHIP 1608 K/X7R/0.047µF/50V CHD473EYA032 CN101 CONNECTOR PRINT OSU JS-1125-06(K) or J3JT06CHY001 C802 CHIP CERAMIC CAP .(1608) B K 0.047µF/50V or CHD1JK30B473 PH CONNECTOR TOP 6P B6B-PH-K-S J3PHC06JG029 (LF)(SN)
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Ref. No. Description Part No. Ref. No. Description Part No. DIODE ZENER HZS5.6NB2TE-EQ QDTB0HZS5R6N D511 SCHOTTKY BARRIER DIODE SB340 NDWZ000SB340 D309 DIODE ZENER 5V6BSB-T26 or NDTB5R6BST26 D512 DIODE ZENER 24BSB-T26 or NDTB024BST26 DIODE ZENER HZS5.6NB2TE-EQ QDTB0HZS5R6N DIODE ZENER HZS24NB2TE-EQ QDTBHZS24NB2 D310 DIODE ZENER 3V9BSB-T26 or NDTB3R9BST26...
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Ref. No. Description Part No. Ref. No. Description Part No. DIODE SWITCHING 1N4148-F0021 NDTZ01N4148F L303 INDUCTOR 12µH-J-26T LLAXJATTU120 D546 SWITCHING DIODE 1SS133(T-77) or QDTZ001SS133 L304 INDUCTOR 12µH-J-26T LLAXJATTU120 DIODE SWITCHING HSS4148TE-E or QDTZ0HSS4148 L601! LINE FILTER MS036 or LLBG00ZY2009 DIODE SWITCHING 1N4148-F0021 NDTZ01N4148F LINE FILTER JLB2808 or LLBG00ZXB004...
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Ref. No. Description Part No. Ref. No. Description Part No. NPN TRANSISTOR 2SC5343MG-AT or NQSG2SC5343M NPN TRANSISTOR 2SC5343Y -AT or NQSY02SC5343 NPN TRANSISTOR 2SC5343M Y NQSY2SC5343M NPN TRANSISTOR 2SC5343G-AT or NQSG02SC5343 Q403 TRANSISTOR 2SA1020-Y(TE6 F M) or QQSY2SA1020F NPN TRANSISTOR 2SC5343MG-AT or NQSG2SC5343M TRANSISTOR KTA1281-Y-AT/P NQVYKTA1281P...
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Ref. No. Description Part No. Ref. No. Description Part No. RES CHIP 1608 1/10W J 47k Ω PNP TRANSISTOR 2SA1980M Y or NQSY2SA1980M RRXA473YF002 CHIP RES. 1/10W J 15k Ω or PNP TRANSISTOR 2SA1980MG-AT NQSG2SA1980M R211 RRXAJR5Z0153 RES CHIP 1608 1/10W J 15k Ω Q521 TRANSISTOR 2SC2120-Y(TE2 F T) or QQSY2SC2120F...
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Ref. No. Description Part No. Ref. No. Description Part No. RES CHIP 1608 1/10W J 560 Ω CHIP RES. 1/10W J 10k Ω or RRXA561YF002 R423 RRXAJR5Z0103 CHIP RES. 1/10W J 15k Ω or RES CHIP 1608 1/10W J 10k Ω R324 RRXAJR5Z0153 RRXA103YF002...
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Ref. No. Description Part No. Ref. No. Description Part No. RES CARBON FILM T 1/4W J 10 Ω or RES CARBON FILM T 1/4W J 1.8k Ω or RCX4100T1001 RCX4182T1001 RES CARBON FILM 1/4W J 10 Ω RES CARBON FILM 1/4W J 1.8k Ω RCJ100PAK001 RCJ182PAK001 CHIP RES.
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Ref. No. Description Part No. Ref. No. Description Part No. RES CARBON FILM 1/4W J 330 Ω RCJ331PAK001 FH605 FUSE HOLDER MSF-015 LF (B110) XH01Z00LY002 RES CHIP 3216 1/4W J 1.0M Ω or R623 RRX4105HH034 FH606 FUSE HOLDER MSF-015 LF (B110) XH01Z00LY002 RES CHIP 3216 1/4W J 1.0M Ω...
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Ref. No. Description Part No. Ref. No. Description Part No. VARISTOR 10D 471K SVR or NVQZVR10D471 C1062 CAP CERAMIC (AX) 1500pF/50V/B/K CA1J152TU061 VARISTOR/Q TVR10471KS42Y NVQKTVR10471 C1063 ELECTROLYTIC CAP . 10µF/50V M or CE1JMASDL100 T601! TRANS POWER BCK-35-0755 or LTT3PE0XB063 CAP ELE 10µF/50V/M/85 or CEF100KSN001 TRANS POWER BCK-35AN LTT3PEMEK011...
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Ref. No. Description Part No. Ref. No. Description Part No. CERAMIC CAP . RB 470pF/2KV or CA3D471TE006 D1006 SWITCHING DIODE 1SS133(T-77) or QDTZ001SS133 CERAMIC CAP . BL 470pF/2KV CA3D471XF003 DIODE SWITCHING HSS4148TE-E or QDTZ0HSS4148 C1552 CHIP CERAMIC CAP .(1608) B K 0.01µF/50V or CHD1JK30B103 DIODE SWITCHING 1N4148-F0021 NDTZ01N4148F...
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Ref. No. Description Part No. Ref. No. Description Part No. DIODE SWITCHING HSS4148TE-E or QDTZ0HSS4148 DIODE SWITCHING 1N4148-F0021 NDTZ01N4148F DIODE SWITCHING 1N4148-F0021 NDTZ01N4148F D1221 SWITCHING DIODE 1SS133(T-77) or QDTZ001SS133 D1121 SWITCHING DIODE 1SS133(T-77) or QDTZ001SS133 DIODE SWITCHING HSS4148TE-E or QDTZ0HSS4148 DIODE SWITCHING HSS4148TE-E or QDTZ0HSS4148 DIODE SWITCHING 1N4148-F0021...
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Ref. No. Description Part No. Ref. No. Description Part No. PNP TRANSISTOR 2SA1980MG-AT NQSG2SA1980M Q1551 TRANSISTOR 2SC2120-Y(TE2 F T) or QQSY2SC2120F Q1005 TRANSISTOR KTC3198-Y -AT/P or NQSYKTC3198P TRANSISTOR 2SC2120-O(TE2 F T) or QQS02SC2120F TRANSISTOR KTC3199-GR-AT/P or NQS4KTC3199P TRANSISTOR KTC3203-Y-AT/P or NQSYKTC3203P TRANSISTOR KTC3198-GR-AT/P or NQS4KTC3198P...
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Ref. No. Description Part No. Ref. No. Description Part No. CHIP RES. 1/10W J 2.2k Ω or TRANSISTOR KTC3198-GR-AT/P or NQS4KTC3198P R1008 RRXAJR5Z0222 RES CHIP 1608 1/10W J 2.2k Ω TRANSISTOR 2SC1815-Y(TE2 F T) or QQSY2SC1815F RRXA222YF002 CHIP RES. 1/10W J 82k Ω or TRANSISTOR 2SC1815-GR(TE2 F T) or QQS12SC1815F R1009...
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Ref. No. Description Part No. Ref. No. Description Part No. METAL OXIDE FILM RES. 1W J 12k Ω or RES CARBON FILM 1/4W J 150 Ω R1050 RN01123ZU001 RCJ151PAK001 METALOXIDE RES 1W J 12k Ω RES CARBON FILM 1/4W J 2.2k Ω or RNJ123PAK001 R1503 RCX4222FS002...
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Ref. No. Description Part No. Ref. No. Description Part No. RES CARBON FILM 1/4W J 12k Ω or RES CARBON FILM 1/4W J 1.5k Ω or R1812 RCX4123FS002 R1970 RCX4152FS002 RES CARBON FILM T 1/4W J 12k Ω or RES CARBON FILM T 1/4W J 1.5k Ω or RCX4123T1001 RCX4152T1001 RES CARBON FILM 1/4W J 12k Ω...
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Ref. No. Description Part No. Ref. No. Description Part No. T1050! TRANS INV ETJV23ZF2WAC LTZ3PZ0MS005 RESISTORS RES CARBON FILM 1/4W J 270 Ω or T1100! TRANS INV ETJV23ZF2WAC LTZ3PZ0MS005 R123 RCX4271FS002 RES CARBON FILM T 1/4W J 270 Ω or T1150! TRANS INV ETJV23ZF2WAC LTZ3PZ0MS005...