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IMPORTANT SERVICE GUIDE ◆ MODE SWITCH (PROGRAM SWITCH) ASSEMBLY POINT 1) When installing the ass’y deck on the Main PCB, be sure to align the assembly point of mode switch. ASSEMBLY POINT VCR MAIN PCB Fig. 1 ◆ HOW TO EJECT THE CASSETTE TAPE (If the tape is stuck in the unit) 1) Turn the Gear Worm Œ...
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Metal Part cal return path to the chassis. Any current measured must not exceed 0.5mA. Reverse the instrument power cord plug in the out- ohmmeter let and repeat the test. See Fig. 1-1. Fig. 1-2 Insulation Resistance Test Samsung Electronics...
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(5) antenna wiring. Always inspect in all areas tinuously and new instructions are issued whenev- for pinched, out-of-place, or frayed wiring, Do not er appropriate. change spacing between a component and the printed-circuit board. Check the AC power cord for damage. Samsung Electronics...
Components ientified by shading, by( ) or by ( ) in the circuit diagram are important for safety or for the characteristics of the unit. Always replace them with the exact replacement components. Samsung Electronics...
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(6) Do not remove a replacement ESD device from its protective package until immediately before your are ready to install it.(Most replacement ESD devices are packaged with leads electrically short- ed together by conductive foam, aluminum foil or comparable conductive materials). Samsung Electronics...
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◆ Be sure to put on a wrist strap grounded to the sheet. ◆ Be sure to lay a conductive sheet made of copper etc. Which is grounded to the table. Samsung Electronics...
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3) Make solder land 2 points short on Pick-up. (See Fig. 1-4) 4) Disassembly the Pick-up. Note : If the assembly and disassembly are not done in correct sequence, the Pick-up may be damaged. PICK-UP ASS'Y SOLDER LAND 2 POINTS SHORT Fig. 1-4 Samsung Electronics...
SOUND TEST EFFECT Head Switching Adjustment ; MODE DIGEST 100+ REPEAT STEP ZOOM ANGLE TV VOL. CH/TRK AMP VOL. TV INPUT SELECT FM/AM INPUT ENTER RETURN MARK TITLE SUBTITLE SCREEN FIT SEARCH SPEED TIMER AUDIO TV/VCR Fig. 2-1 Samsung Electronics...
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Alignment and Adjustments 2-1-1(b) TEST location for adjustment mode setting TEST (SW718) BUTTON Fig. 2-2 Function-Timer PCB (Top View) Samsung Electronics...
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Alignment and Adjustments 2-2 DVD Adjustment 2-2-1 Location of Test Point Fig. 2-5 Location of test Point (DVD Main PCB - Top Side) Samsung Electronics...
(See Fig. 2-6) (See Fig. 2-5) ◆ SKEW (Tangential) : The shift on the Vertical axis of Spindle Motor movement. ◆ SKEW (Radial) : The shift on the Direction of the Spindle Motor movement. Fig. 2-6 Ass’y Deck (Bottom Side) Samsung Electronics...
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If you cannot obtain a Flat waveform, then the unit is defective. Note : The Deck must be in a horizontal position. Use both “A” and “B” screws to adjust, but mostly “A”. Typical Waveform before Adjustment Waveform after Correct Adjustment Fig. 2-7 Envelope Waveform Samsung Electronics...
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Test Point Adjustment Location “RF EQC” TDV-525 1.7 ± 0.2V (DVD Main PCB - Top Side) (DVD Main PCB - Top Side) (See Fig. 2-5) (See Fig. 2-8) Fig. 2-8 Location of VR1 (DVD Main PCB - Top Side) Samsung Electronics...
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4) Adjust according the to table on the previous pages : ◆ 1.7V ± 0.2V ⌘ Warning : Do not turn the Voltage up too high, as this may damage the Laser Diode permanently. Fig. 2-9 RF SUM Level Wavefrom Samsung Electronics...
Fig. 2-10 Location of Tape Transport Adjustment PINCH ROLLER FE HEAD CYLINDER ASS'Y GUIDE ROLLER "S" GUIDE ROLLER "T" POST TENSION #8 GUIDE POST #9 GUIDE POST #3 GUIDE POST MAIN BASE ACE HEAD CAPSTAN SHAFT Fig. 2-11 Tape Travel Diagram Samsung Electronics...
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HEIGHT ADJUST X-POSITION ADJUSTING SLIT SCREW (B) SCREW (D) AZIMUTH ADJUST X-POSITION LOCKING Fig. 2-12 Location of ACE Head Adjustment Screw AUDIO HEAD VIDEO HEAD 0 ~ 0 .25 mm CONTROL HEAD Fig. 2-13 ACE Head Height Adjustment 2-10 Samsung Electronics...
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Fig. 2-14 Tape Guide Check c. AUDIO AZIMUTH ADJUSTMENT 1) Load alignment tape (Mono scope) and playback the 7KHz signal. 2) Connect channel-1 scope probe to audio output. 3) Adjust screw (B) to achieve maximum audio level. (See Fig. 2-12) Samsung Electronics 2-11...
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5) Insert the (-) driver into the X-Point adjustment hole and adjust it so that envelope waveform is maximum. Test point : TP2 (Audio Output) TP3 (Envelope) TP4 (H’D S/W -Trigger) TP5 (Control Pulse) CONTROL PULSE HEAD SWITCHING ENVELOPE AUDIO OUTPUT Fig. 2-15 Location of Test point (VCR Main PCB-Top View) 2-12 Samsung Electronics...
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5) If the section B in Fig. 2-17 does not meet the specification, adjust the guide roller T up or down. a b c d c,b,d/a Fig. 2-16 Envelope Waveform Adjustment H'D SWITCHING PULSE ENVELOPE Fig. 2-17 Adjustment Points Samsung Electronics 2-13...
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) driver to obtain a flat video RF envelope as shown in Fig. 2-18. IDEAL ENVELOPE S HEIGHT TOO HIGH S HEIGHT TOO LOW T HEIGHT TOO HIGH T HEIGHT TOO LOW GUIDE ROLLER S GUIDE ROLLER T Fig. 2-18 Guide Roller S, T Height Adjustment 2-14 Samsung Electronics...
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2) If excessive tape wrinkle is observed, perform the following adjustments in Playback mode : ◆ Tape wrinkle at the guide roller S, T section : Linearity adjustment. ◆ Tape wrinkle at tape guide flange : ACE head assembly coarse adjustment. Samsung Electronics 2-15...
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4) Transportation of accurate driving force is done by gears. (Gear Center Ass’y) Note : If the spec. does not meet the followings specifications, replace the holder clutch ass’y and then recheck. <Table 2-4> MODE TORQUE g/cm GAUGE 42 ± 11 Cassette Torquemeter 145 ± 30 Cassette Torquemeter 2-16 Samsung Electronics...