This service manual is only for service personnel to take reference with. Before Attention: servicing please read the following points carefully. Safety instructions 1. Instructions Be sure to switch off the power supply before replacing or welding any components inserting/plugging in connection wire Anti static measures to be taken (throughout the entire production process!): a) Do not touch here and there by hand at will;...
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would be unable to work and no way to get it repaired. If the connection wires, connectors or components fixed by the thermotropic glue need to disengage when service, please soak the thermotropic glue into the alcohol and then pull them out in case of dagame.
Alignment instruction 1 Alignment equipment PM5518 (video signal generator) K-7253 (VGA signal generator) CA210 (white balancer) IF signal generator Signal generator Oscillograph 2 Alignment flow-chart The alignment flow-chart is shown as fig-1 Write memory N300 and N400 To produce main board and power supply board Check power supply board and main adjustment All testing Connect with central signal source, then check each function of TV(Station...
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SYSTEM) for X210, input 9v(±0.05v) and 5v(±0.05v) to J202 and J203, adjust L210 to let x205 voltage to be 1.65v(±0.1v). b. Solder to J201, J202, J203 and J5 3.3.2 AGC adjustment Receiving 60dB signal of D-8 or A-7(N system), adjust RP201 to let 3v(±0.05v) of X204. Input 100dB of antenna, the picture should not no-sync and distortion.
800 x 600 @ 60 40.000 37.879 60.317 1024 x 768 @ 60 65.000 48.363 60.004 1024 x 768 @ 70 56.48 70.07 1280 x 1024 @ 60 109.47 63.72 e). YPbPr Interface Input YPbPr signal to YPbPr/YcbCr interface. Separately input the several types of YPbPr format signals: 480P/60Hz, 480P/59Hz;...
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red LED at the front of the TV set) See if it’s receiving the signal that is transmitted from other source than the station Check if it’s connected to the wrong terminal or if the input mode is correct. Check if the signal cable connection between video source and the liquid crystal TV set is correct.
Check if the sound volume is set to minimum. Make sure the earphone is not connected. Check if the cable connection is loose. When playing VHS picture search When being played or in pause VHS picture search tape, there are lines at the top or tape sometimes can’t provide stable picture, which bottom of the picture.
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5. Connect the VGA MONITOR interface on the Y# updating board with the VGA cable, connect the other end to the VGA interface of the LCD. 6. Turn on the LCD 7. Run Gprobe5 Click the icon of Set the Device to Parallel. The click the item of Delays and Buffer Size: Set Long to 50000 ms.
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Select the path of the File: bat.txt Select bat.txt and click to open it: Click “OK” to start the process of burning the program. The following screen appears when the process if finished. If you want to update the software next time, you just need to click the pull-down menu to select the desired Batch file and execute it in the following screen.
The unit working principle analysis For the PAL system, when the RF signal is input to the tuner, the turner generates IF signal. Then the IF signal goes through the pre-amplifying circuit and 38M SAW, the VIF signal and 1ST_SIF signal will be generated.
As follows we are going to introduce the inner IC block diagram and function. 1. Inner block diagram of M52760 IF signal processing IC (AFT, QIF, VIDEO OUT) Descriptions of the pins: Description Description 4, 5 VIF input QIF OUT 1ST_SIF input AUDIO OUT VIDEO OUT...
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2. Inner block diagram of LA72700 stereo decoder...
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Descriptions of the pins: Pin name Connections Pin name Connections PCSTFILT VCO PLL filter IIC data input PCPLDET Driving level test IIC clock input PISIF SIF signal test PCALCFIL ALC filter 25/26 R/L OUT TVF_R/L output SIF DEMOD SIF demodulator PCREC Reference voltage MUTE...
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6. Inner block diagram of FLI8125 digital video processing IC The descriptions of the pins of FLI8125IC Pin name Connections Pin name Connections KEYA Key A S-video terminal identification KEYB Key B Pulse width adjustment AUD_SEL_1 RESETn Reset AUD_SEL_2 XTAL Resonator PBIAS Panel’s oblique line control...
Troubleshooting charts 1. No raster, no picture and no sound When the main power is turned on, the unit’s indicator lights up in red (red indicator is controlled by +3.3VSTANDBY), use the remote control or the unit’s STANDBY to lights up the blue indicator. Power board’s +3.3V Whether the IR board’s is abnormal...
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2. With picture and without sound when turning on: Increase volume; Check if the no sound channel from the signal check whether every input to sound processing IC IC15900 is normal channel has no sound Check whether the signal 15900(IC) or peripheral circuit output by 15900(IC) is does not work normally normal...
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5. Check flow of the power board (20”): Replace the fuse and check Power board damages Replace N501, D501 whether N501, D501 or fuse blows breakdown Check whether C512 has 18V Replace D502 Check whether pin1 of N501 has wave Check whether N502 is damaged Replace N502 Check whether N505, D507 is...
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PART LIST OF EXPLODED VIEW DESCRIPTION IR board Front cabinet Speaker Key board Panel Backlight board Power board Back cabinet Stand Main baord User manual Remote control...
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PART LIST AVL209 ver. REF.No. PARTS No. DESCRIPION Q'TY REMARK IR board XI6LY0150910 Front cabinet XI5QP19W103A XI617A539000 Speaker XI6LY01505A0 Key board Panel 1 AU T200XW02V0 Backlight board XI6LY01414A0 Power board XI6LY0142010 Back cabinet XI5HP19WH04B XI6151059320 Stand XI6LY03001A0 Main baord User manual...