/ or other hazards. Product safety is under review continuously and new instructions are issued whenever appropriate. Components identified by on schematics and parts lists must be sealed by a soldering iron after replacement and adjustment. CF21M*...
3 Disassembly and Reassembly This section of the service manual describes the disassembly and reassembly procedures for the CF21M* monitor. WARNING: This monitor contains electrostatically sensitive devices. Use with caution when handling these components. 3-1 Disassembly Cautions:1. Disconnect the monitor from the power source before disassembly.
Composite sync 0.3 Vp-p negative ET-4000 chipset (strongly recommended if (Video 0.7 Vp-p positive) using Samsung DM 200 software) and that displays: 1280 x 1024 @ 85 Hz, or 1600 x 1200 4-1-1 (d) SCANNING FREQUENCY @ 85 Hz (maximum).
(Is it same the schemetic diagram) Check IC651 (KA78R12) Pin 12? • Appear 4V Pin 4 of IC651? Is the voltage 12V • Done. Check and Micom. (IC201) Check and replace IC651. • Check every IC connected to 12V. • CF21M*...
Check IC201 Pin 25 Does +12V Line off? or replace IC201. (Check the IC651 output Pin 2) Does +14V_V Line off? Check Q671, D670. (Check the Q670 Collector) Check IC201 Pin 23 Does the Q620 activate? or replace IC201. Done. CF21M*...
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Check DY connector connection. WAVEFORMS IC402, #6 Q454, Drain Q401, Gate CH1 P-P = 10.96 V CH1 RMS = 6.180 V CH1 P-P = 11.6 V CH1 RMS = 6.944V Q401, Drain Q402, Base Q402, Collector CF21M*...
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Check some parts around IC403. Check L403. 5-1-7 Invariable H_Size D250 Cothode voltage varies with Check and replace IC250, IC201. different H_Size DAC values? IC402 Pin 6 output duty varies with Check some parts different H_Size DAC values? around IC250, IC201. CF21M*...
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Check and replace IC250. The waveform is right? Check and replace IC402. WAVEFORMS Check some parts IC402 Pin 2 and IC250 Pin 24. IC250, #24 5-1-10 Para. or Pin Balance Failure IC250 Pin 24 output varies with different DAC values? Replace IC261. CF21M*...
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Refer to 5-1-1 No Power supply. IC250, #23 IC250 Pin 23 output exists? Check and replace IC250. The waveform is right? IC301 Pin 6 output exists? Check and replace some The waveform is right? parts around IC301. IC301, #6 Check V DY connector connection. CF21M*...
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Q504 gate driving pulse exist? Check and replace The waveform is right? Q502, Q503, R511, IC501. Q504, Gate Are there some voltages Check and replace Q504, D508, (350V, 30V, -210V, etc) D509, D530, D507, D505. at secondary part of FBT? Done. CF21M*...
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Does the voltage of Q541 collector change as the FH function Check Q541 and others components. CH1 P-P = 580 V CH1 RMS = 278.2 V is changed on the OSD menu? Check the connection between FBT Pin 13, CRT Socket PCB. CF21M*...
Are there waveforms at CRT Check and replace IC105 Socket Pin Red, Green, Blue? (19”:IC102) and components around IC105 (19”:IC102). G2 voltage is right? Check D598, D599 and G2 wire. Heater Voltage is right? Check CN102 wire Assy. Change CRT. Done. CF21M*...
CH1 P-P = 3.42 V CH1 RMS = 2.500V IC201 Pin 40 input is High Active? Check and replace IC202. 3.16 V (IC201, #32) All in/output values are right? Replace IC201. CH1 P-P = 3.16 V CH1 RMS = 2.560 V Done. 5-10 CF21M*...
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Check and replace IC103 (19”:IC103). Pins 1, 4 and 9, 13) input is right? IC103, #5, 24 Does the Voltage Change on IC201 Pins 11, 12 When you Check CN204 and Assy. push the control Button? Check IC201. Done. CF21M* 5-11...
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Done. 5-1-21 Degaussing Failure Check degaussing connector. RL601 operation is right? Check D-Coil, POS601. Q601 base input is right? Check and replace Q601. Check and replace IC201. IC201 Pin 31 output is right? Check user function key. Done. 5-12 CF21M*...
Replace the CRT. 5-2-2 Shut Down LED is blinking so fast Check SDA (IC201 Pin 30) and SCL (Once per 300m sec)? (IC201 Pin 29) Replace IC280, IC201. LED is blinking once a second? Check signal cable and signal source. CF21M* 5-13...
Proper DC voltage are Pin 1, 3 and 5. on all cathodes? Check and replace IC105 (19”: IC102) and IC104 (19”: IC104). Check D598, D599 and G2 wire. G2 voltage is right? Check around FBT circuits also. Change the CRT. Done. 5-14 CF21M*...
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Check IC102 (19”: IC101) Pin 25, 28 and 30 of IC102 and related components. (19”: 29, 32 and 35 of IC101)? Is V_FLB and DC_bias on Check Q301, CN102 Assy, G1 Pin at CRT socket? Q520, D520, and D521. Done. CF21M* 5-15...
IC250 Pin 23 and 26 right? Are H_FLYBACK of IC102 Pin 23 Check CN102 Assy and Q103. (19”: IC101 Pin 27) right? Check clamp pulse of IC102 Pin 22 (19”: IC101 Pin 19) replace IC201 and Q107. Done. 5-16 CF21M*...
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(CN104, CN105). Proper voltage are appeared Check and replace IC106. The convergence is on IC106 Pin 7, 8, 10, and 11 now within spec.? in Video Board. Change CRT and readjust convergence. Change CRT and readjust convergence. Done. Done. CF21M* 5-17...
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Refer to 5-1-15 Dynamic Dynamic focus circuit is right? Focus Failure. Replace the CRT and verify focus. 5-2-8 Purity Failure Degaussing Purity is right? Done. Degaussing circuit is right? Refer to 5-1-20 Degaussing Failure. Replace CRT and verify purity. 5-18 CF21M*...
(Horizontal x Vertical Size Table) CONDITIONS Scanning frequency: 91 kHz / 85 Hz 21” Display image: Crosshatch pattern Horizantal Brightness: Cut-off Contrast: Maximum 294.5 Vertical Click on the << or >> box next to H_POSI to center the horizontal image on the raster. CF21M*...
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“@4: USER DELETE” in right menu. 4-2-5 Parallelogram Adjustment CONDITIONS Scanning Frequency: 91 kHz / 85 Hz Display image: Crosshatch pattern Brightness: Cut-off Contrast: Maximum Use control bar after selecting “PARALLEL” in left menu to make the image area rectangular. CF21M*...
3. Select COLOR FACTORY SAVE to save the CUTOFF” in left menu to 0.283 ± 0.015 data. * If color values would not be matched desirable values, repeat sequence 3 and 4 after readjusting “GREEN CUTOFF” control a little different. CF21M*...
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Adjust the brightness of the G_GAIN less 2 ft-L 3. Click on the << or >> boxes next to R_CUT than brightness of procedure for 9300K. and B_CUT to adjust the R-Bias to x = 0.313 ± 0.02 and the B-Bias to y = 0.329 ± 0.02. CF21M*...
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(For 9300K color adjustment: x = 0.283 ± 0.02, y = 0.298 ± 0.02) Scanning frequency: 91 kHz / 85 Hz 7. When you have the PCMs properly adjusted, Display image: “H” character pattern carefully glue them together to prevent their Brightness: Cut off point movement during shipping. Contrast: Maximum CF21M*...
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4 plastic ties on the Bracket. side. 2. Lift the Degaussing Coil Assembly from the 3. Disconnect CN201, CN409, CN601, H_DY, Bracket. CN604 and Anode Cap on the Main PCB Assembly. 3-2 Reassembly Reassembly procedures are in the reverse order of Disassembly procedures. CF21M*...
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B : Horizontal sync width O : Frame time total P : Vertical sync width C : Back porch D : Active time Q : Back porch R : Active time E : Front porch S : Front porch CF21M*...
“anti-static” a carpeted floor can generate enough static can generate electrical charges sufficient to damage electricity to damage an ESD. ESDs. Indicates ESDs on the Schematic Diagram in this manual. CF21M*...
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Samsung Electronics Co.,Ltd. 416, Maetan-3Dong, Paldal-Gu, Suwon City, Kyungki-Do, Korea. Printed in Korea P/N : BH81-00017A-00 http://www.samsungmonitor.com (SyncMaster Worldwide) http://www.samsung-monitor.com (SyncMaster USA) http://www.sec.co.kr/monitor (Korea)