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S/M No. :VKB2121NN0 Service Manual COMBO TIMELAPSE VCR Model : DQ-K2121N-P Caution : In this Manual, some parts can be changed for improving, their performance without notice in the parts list. So, if you need the latest parts information,please refer to PPL(Parts Price List) in Service Information Center (http://svc.dwe.co.kr).
SAFETY & PRECAUTIONS SAFETY CHECK AFTER SERVING Examine the area surrounding the repaired location for damage or deterioration. Observe that screw, parts and wires have been returned to original positions. Afterwards, perform the following tests and conform the specified values in order to verify compliance whit safety standards.
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SAFETY & PRECAUTIONS 4. Leakage current test Confirm specified or lower leakage current between B(earth ground, power cord plug prongs) and externally exposed accessi-ble parts (RF terminals, antenna terminals, video and audio input 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.
FEATURES & SPECIFICATION GENERAL FEATURE NTSC SYSTEM REMARK DESTINATION NTSC : NORTH AMERICA COLOR SIGNAL NTSC : NTSC EFFECTIVE PICTURE SIZE 14Ó -> HEIGHT : 8.27Ó(21cm), WIDTH : 11.00Ó(28cm) 20Ó -> HEIGHT : 13.27Ó(34Cm) , WIDTH : 17.09Ó(43Cm) CALENDAR 2003~2102 OSD LANGUAGE ENGLISH Only LETTER COLOR...
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FEATURES & SPECIFICATION FEATURE NTSC SYSTEM REMARK MENU 2. VCR Mode Set 1) Tape Search Select - Alarm Search 01/02/03 . . . 99 <First condition : - -> 01/02/03 . . . 99 <First condition : - -> - Index Serach Forward Search Reverse Search - Zero Search...
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FEATURES & SPECIFICATION RECORDER FEATURE NTSC SYSTEM REMARK Deck Mechanism Head Width NTSC: RÕ:48µm, L:26µm/R:26µm, LÕ:58µm Full Loading - Condition in Power off Unloading Stop ->Play Time About 1Sec FF->REW Time 3 min Under(T-120/E180 TAPE) Dew Sensor Auto Head Cleaner DLC Coated Drum Video Video Head...
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FEATURES & SPECIFICATION FEATURE NTSC SYSTEM REMARK Timer Auto Series Record Auto Repeat Record Yes(MENU SET) Alarm Search Yes(MENU SET) Clock Display Method 24Hours Timer Recording System With the Timer Key Alarm Recording System Yes(When the Stop Key is clear immediately) NTSC SYSTEM : 02/06/18/30H Repeat Recording System Yes(MENU SET)
EXTERNAL VIEWS 2. BACK VIEWS WARNING TAPE ALARM IN 1 IN 2 IN 3 IN 4 AUDIO MONITOR VIDEO POWER INPUT RESET AUDIO CH 1 CH 2 CH 3 CH 4 AUDIO IN (CH1~CH4, rca type) Terminal 1) N.C. 2) N.C. VIDEO IN(CH1~CH4, bnc type) 3) WARNING OUT 4) COM...
EXTERNAL VIEWS 3. REMOCON USER REMOCON SVC MODE BY USER REMOCON * SVC MODE 1.POWER ON(EJECT) 2.Make full screen in CAM4. 3.Push "INDEX -, +, ALARM -, +" buttons in sequence within 10 seconds. 4.Press the POWER OFF key to release SVC MODE. e.20"/14"...
ALIGMENT INSTRUCTIONS 1. VCR DECK ADJUSTMENTS 1) X-DISTANCE & P2,P3 ADJUSTMENT(S10) ¥ Connect Path JIG to connector PS 04, Playback the test tape(DN-2,7KHz) ¥ Connect oscilloscope CH1 to V.SW(PS04#2), CH2 to PB RF(PS04 #1) and trigger on CH1. ¥ Enter the service mode and select service adjustment S10 ¥...
ELECTRICAL ADJUSTMENT Electrical adjustments: Alignment and electrical adjustment - For these adjustments, use the equipment mentioned below and proceed by using the alignment tape and video signal. ¥ Instrument and tools required 1. Color TV . 2. Oscilloscope having 10MHz or more bandwidth. 3.
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ELECTRICAL ADJUSTMENT 1. SERVO/SYSCON CIRCUIT ADJUSTMENT METHOD (1) VIDEO HEAD SWITCHING POSITION Adjustment Part Checking Point Measuring Equipment Mode Test Tape R595 TJ396P502 3PIN Oscilloscope Play DN-1(Color Bar) ¥ Connection Method R595 TJ396 P502 CH-2 Oscilloscope CH-1 ¥ Adjustment Procedure 1) Play back the test tape.
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ELECTRICAL ADJUSTMENT 2 . MONITOR ADJUSTMENT * HOW TO ENTER THE SVC MODE 1) POWER ON(EJECT MODE) and make full screen in CAM4. 2) Push INDEX-,+,ALARM-,+ buttons in sequence within 10 seconds. Then, the screen will display FACTORY V0.1 text on the upper of the reft. 2-1 The adjustment of screen 1) Press the VOL UP, DOWN(S-BRIGHT +,-) key on the remote control to set the sub-bright.
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ELECTRICAL ADJUSTMENT 2-4-2 The adjustment of vertical size 1) Apply NTSC RETMA pattern. 2) Call up the SVC Mode and make full screen in C4 3) Press MENU,PIP(V-SIZE+ or V-SIZE-) key and VERT SIZE OSD will be displayed. 4) Adjust with MENU,PIP(V-SIZE+/V-SIZE-) keys so that the upper and the lower Ô+Õ marks of the RETMA pattern may be located at the boundaries of the screen.
CIRCUIT OPERATION 1. VIDEO PART 1-1) EE MODE Video Signal which is output from monitor is input into pin 36 of IC301. It is amplified 6dB by AGC, then it is output to pin 29 of IC301. The output signal is output to monitor through PJ301.. 1-2) REC MODE Video signal inputted from monitor will be recorded on the tape through head after FM modulated in IC.
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CIRCUIT OPERATION 2. AUDIO PART 2-1) EE MODE External AUDIO signal which is input to pin 78 of IC301 is output from pin 96 of IC301 after being ampli-fied through ALC and Line Amp. 2-2) REC MODE It will be the REC mode when REC 5V is input to base of Q206,Q202. Input signal will be replaced on the tape through R/P HEAD after being amplified and modulated with Bias Frequency.
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CIRCUIT OPERATION 3. SYSTEM PART 3-1) System Block DIAGRAM Terminal Jack CRT & PART DY COIL VCR Servo Syscon . OSC PART PART & High Multiplexer Volt price Part DECK K Monitor MECH K-30 u-com IC Front KEY Matrix Coil Power PART Degauss...
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CIRCUIT OPERATION 3-2) TIME LAPSE RECORDING METHOD The numbers of VHS 2HOUR (SP), 6HOUR (EP) REC FIELD are 60 field/sec, then it will be 1FRAME = 33.3Ms, 1FIELD = 16.65Ms. CAPSTAN MOTOR FG numbers for Time Lapse are 6HOUR(EP) = 720 numbers/sec, 2HOUR(SP) = 720*3=2160 numbers/sec.
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CIRCUIT OPERATION 3-3) TERMINAL PART ALARM INPUT 1,2,3,4 Connect DOOR SW&SENSOR etc and this port will be used for emergency recording by using open/ close status. N/O(NORMALY OPEN) 500ms N/C(NORMALY CLOSED) 500ms TAPE END OUT When the recording tape ends during recording, end sensor will be detected. This port is used Alarm to outsider until release the end sensor detecting.
TROUBLESHOOTING FLOW CHART 1. VIDEO CIRCUIT A. TROUBLESHOOTING OF EE MODE Is VIDEO signal obtain from Check MUX. pin5 of P301? Is E9V supplied at Q 303? Check Q 303. Is the video signal to emitler of Q303? Check power. Is signal input into Check Q303.
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TROUBLESHOOTING FLOW CHART B. TROUBLESHOOTING OF RECMODE Is the video signal input into RECHECK METHOLD A. pin36.of Ic301? Is ON/OFF 5V supplied to Check ON/OFF 5V. IC301 at 5V? Is the luminance signal from pin21 of IC301 fed to pin20 of IC301? Check Q302,C311 Is the color signal from pin72 Check IC 301.
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TROUBLESHOOTING FLOW CHART C. TROUBLESHOOTING OF LUMINANCE IN THE PLAYMODE Is envelope output Is 5V supplied at Check power. pin 87 of IC 401?. from pin 74 of IC 301? Is SW pulse input at Check IC 501. pin 11 of IC 301?. Check P401 and DRUM head.
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TROUBLESHOOTING FLOW CHART D. TROUBLESHOOTING OF COLOR IN THE PLAYMODE. Is color signal from pin72 fed to pin71 Check IC 401. of IC 301? Is the signal obtained from Check IC301. pin 51 of IC 301? Is color Rotary pulse supply to Check IC 501.
TROUBLESHOOTING FLOW CHART 2. SERVO-SYSCON CIRCUIT Playback picture Adjust tracking. is not good Noise appears Noise appears Check and re-adjust although although change the path of Deck. adjusting tracking. cassette tape. CTL HEAD height Adjust the HEAD Is CTL pulse output is normal and height and at pin 2 of P502?
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TROUBLESHOOTING FLOW CHART Playback picture is not good. Noise appears on the Noise appears on the Check flow A. screen on the whole. screen at the bottom Check the PG Adjustment. Is SW-pulse applied to Is sw pulse supplied Check D.PG input video IC? from pin 18 of IC501? and connector.
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TROUBLESHOOTING FLOW CHART Auto-stop during playback. Is reel pulse applied to Check reel sensor. pin 79 and 80 of IC501? Is D. FG applied to Check connector and pin 89 of IC501? D. FG circuits. Check IC501.
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TROUBLESHOOTING FLOW CHART Drum M/T loading stops. Is motor 12V supplied Check circuit adjacent from IC 503? EVER +12.4V. Check power module. Is 5.2V supplied from Check IC808. P506 pin 5? Check connector and motor.
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TROUBLESHOOTING FLOW CHART Capstan M/T loading stops. Check IC808. Is motor 12V supplied? Is the input of pin 6 Check circuit of C547, of P505? R548,R531,R547,R551,C548 Check R549, R552 Is pin 4 of P505 2.5V? Does pin 77 of IC501 Check IC501.
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TROUBLESHOOTING FLOW CHART Drum M/T and capstan M/T rotate at irregular speed. (IN REC MODE) Is C. sync applied to Check C. sync of video pin 93 of IC501? IC and pattern. Check motor Emergency mode when plugging (power cord) Is ever 5V applied? Check IC810.
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TROUBLESHOOTING FLOW CHART Cassette is not inserted. Check power Module. Is motor 12V supplied? CAM DATA is changed Check connector. when CST IN? Is 5V supplied at Check Deck part. pin 31 of IC501? Check pattern Check IC501. and R572.
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TROUBLESHOOTING FLOW CHART Power compensation does not operate. When mains is unplugged, Check C586, is 3.6V at pin 37 of IC501? C501,C515,C516 Is (sine) signal applied to Check X501. pin 38 and 39 of IC501? Check reset circuit Is 5V at pin 37 of IC501? Of IC504.
TROUBLESHOOTING FLOW CHART 3. AUDIO CIRCUIT A. TROUBLESHOOTING OF PB MODE No sound in the playback mode. Set AUDIO ON key to ON. Is AUDIO ON key set to ON? Check PJ 201 Is signal input pin 5 of IC 301? &...
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TROUBLESHOOTING FLOW CHART B. TROUBLESHOOTING OF REC MODE No sound in the playback mode after recording. Set AUDIO ON key to ON. Is AUDIO ON key set to ON? Is signal input pin 78 Check monitor PART. of IC301? Is the voltage above 4V Check SERVO SYSCON.
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TROUBLESHOOTING FLOW CHART C. TROUBLESHOOTING OF EE MODE No sound in the EE modes. Is 12V applied to pin 16 Check IC806, IC807 of IC 943,IC942? Is signal input Check Audio switch part. pin 78 of IC 301? Is signal output Check IC 301.
TROUBLESHOOTING FLOW CHART 4. POWER PART When power is not on Check power cord AC120V at the both side and power switch. of S801? Check D801, D802,D803, DC 150V at the +side of C805 D804, R802 Oscillater Signal at the Check IC801.
TROUBLESHOOTING FLOW CHART 5. MONITOR PART In case the monitor screen does not appear. DC133V at the pin10 of Check the power part. PJ801? Check T802 and Pin42 Does Q802 Oscillate? of IC401 B(+), HEAT Signal at the Check T803. PIN2,3 of PJ804? Vertical signal and Drive(+),(-) Check IC805, IC401...
TROUBLESHOOTING FLOW CHART 6. MUX PART Is the EE SCREEN (Monitoring screen)wrong? Video Input signal at Check video switch part. pin 3,5,7,9 of P001? VIDEO Signal at the pin30 Check IC 010, P003. of IC000? VIDEO Signal at the Check IC011. pin6 of IC012? VIDEO Signal at the pin20 Check the pattern.
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TROUBLESHOOTING FLOW CHART When the Rec Screen is wrong? VIDEO Signal at the Check video switch part. pin3,5,7,9 of P001 ? VIDEO Signal at the pin30 Check IC 010, P003. of IC007? VIDEO Signal at the Check IC011. pin3 of IC012? VIDEO Signal at the pin50 Check the pattern.
VCT 3834 PIN ASSIGN NC = Not Connected, LV = if not used Leave Vacant, X = Obligatory : connect as described in circuit diagram PinNo. Pin Name Type Connect(if not used) Descriptions Key 1 I/O ( I ) Key Matrix 1 input. Ñ> Not used (connected 3.3V) System Sel I/O ( I ) Key Matrix 2 input.
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VCT 3834 PIN ASSIGN PinNo. Pin Name Type Connect(if not used) Descriptions RSW1 Range Switch for Measuring ADC.Open Drain Pulldown Outputs.The switch is off while the Cutoff and the whitedrive are measured. RSW2 Range Switch for Measuring ADC.Open Drain Pulldown Outputs.The switch is off while the Cutoff is measured.
µ -COM PORT DESCRIPTION Pin No. Pin Name Type Connection Short Description START SENS IN/OUT ANALOG START SENSOR VOLTAGE INPUT MD OUT IN/OUT MONITOR COMMUNICATION SIGNAL OUTPUT POWER FAIL IN/OUT POWER SUPPLY VOLTAGE LEVEL INPUT ALARM IN2 IN/OUT CAMERA2 ALARM SIGNAL INPUT CAM B IN/OUT CAM SIGNAL INPUT...
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µ-COM PORT DESCRIPTION Pin No. Pin Name Type Connection Short Description VIDEO IN COMPOSITE VIDEO SIGNAL INPUT LECHA WHITE LEVEL INPUT VIDEO OUT IN/OUT COMPOSITE VIDEO SIGNAL OUTPUT OSD Vcc OSD POWER SOURCE INPUT IN/OUT FILTER CONNECTION PIN FOR SLICER M CLK IN/OUT MONITOR COMMUNICATION SIGNAL OUTPUT...
Ris a recommendable part for stock. 1. PCB MAIN AS PART-CODE PART-NAME PART-DESC REMARK PART-CODE PART-NAME PART-DESC REMARK PVMCASN667 CHASSIS MAIN AS DQ-K2121N-P AL03 2291050305 FLUX LIQUID RF-800KN A0010 97SA309700 MAIN BASE AS K-MECHA AL04 2291050306 FLUX THINNER RF-800ADD...
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ELECTRICAL PARTSLIST PART-CODE PART-NAME PART-DESC REMARK PART-CODE PART-NAME PART-DESC REMARK C002 HCFH104ZBA C CHIP CERA 25V Y5V 0.1MF Z 1608 C057 HCBK473KBA C CHIP CERA 50V X7R 0.047MF K 1608 C003 HCBK473KBA C CHIP CERA 50V X7R 0.047MF K 1608 C058 HCBK473KBA C CHIP CERA...
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ELECTRICAL PARTSLIST PART-CODE PART-NAME PART-DESC REMARK PART-CODE PART-NAME PART-DESC REMARK C119 HCFH104ZBA C CHIP CERA 25V Y5V 0.1MF Z 1608 C314 HCQK101JBA C CHIP CERA 50V CH 100PF J 1608 C120 HCFH104ZBA C CHIP CERA 25V Y5V 0.1MF Z 1608 C315 CEXF1C470A C ELECTRO...
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