Technical description and composition of the BBK LT1914S TV, panel type and applicable modules. The composition of the modules.BBK
Model: LT1914S
Chassis / Version: HUDSON
Panel: 19 inch 1440x900
Inverter (backlight): JSI-190411ROH
PWM Inverter: BIT3105
MOSFET Inverter: MI3106 (so8)
Power Supply (PSU): JSI-190411 ROH
PWM Power: SG5841SZ (SO8)
MainBoard: E-RSAG7.820.847A LCD1533EU HUDSON LT1914S
IC MainBoard: FLI8125, SST39VF088-70-4CEKE, MSP34XX, TDA1517
Tuner: DQ-6FT / W116H
Technical Specifications LT1914S
BBK LT1914S
General recommendations for repairing TV LCD
Possible manifestations of defects
- The BBK LT1914S TV does not turn on, does not respond to the remote control and the control panel buttons, does not blink with any indicators.
With such manifestations in most cases, the JSI-190411ROH power supply module is faulty. It is necessary to measure the secondary output supply voltage, and in case of their absence, check the serviceability of the power switches of the converters and rectifier diodes for a short circuit.
In case of breakdowns in the secondary circuits, the converter can operate in a short circuit mode, and during short circuit in the elements of the primary circuit, the mains fuse usually breaks.
The breakdown of Mos-Fet keys used in pulsed sources is often caused by malfunctions of other elements, for example, power supply, frequency-setting, damper ... as well as elements of the Negative Stabilization Feedback. The PWM chip (PWM) SG5841SZ (SO8) can also cause a malfunction of the power switch of the converter and is checked by replacement.
- There is no image, but there is sound, it reacts to the remote control. Or the image appears when you turn it on and immediately disappears
These manifestations can be triggered by a power module, or by defects in the inverter, as well as a distortion of the currents in the lamps due to their uneven wear. If all the electrolytic capacitors of the filter according to the inverter power supply are serviceable, you should make sure that the lamps are working, then you need to check the converter keys and the secondary windings of the transformers.
Sometimes, for diagnostic purposes, inverter protection must be disabled. In such cases, special care must be taken during work, and the protection circuits should be restored immediately after the repair is completed.
- The TV does not enter the operating mode, does not respond to the remote control. The indicator on the front panel lights constantly or blinks.
Repair or diagnostics of the HUDSON motherboard should begin by checking the stabilizers and power converters needed to power the chips and matrix. If necessary, update or replace the software (software). Board repair and replacement of FLI8125, SST39VF088-70-4CEKE, MSP34XX, TDA1517 microcircuits are carried out with the necessary equipment, and the corresponding element base. Faults associated with the application of BGA processor soldering technologies can be localized by the heating method.
If the TV works normally with external devices, but does not tune into television channels, the DQ-6FT / W116H tuner may be malfunctioning. In such cases, first of all, you should make sure that there are supply voltages at its corresponding terminals. It is also necessary to make sure that the tuner and processor can exchange data via the I2C bus. Sometimes the cause of the inoperability of the tuner may be a software failure.
For LT1914S TV owners, we recommend that you contact qualified personnel with the necessary work experience for repairs! Self-repair attempts without the appropriate knowledge and skills can lead to irreversible negative consequences!
Service Manual / Schematic Diagram ----------------------> BBK LT1514S, LT1914S (HUDSON)
Service Manual 24 pages on the LT1514S, LT1914S.
The appearance of the MainBoard E-RSAG7.820.847A is shown in the figure below:E-RSAG7.820.847A
E-RSAG7.820.847A can be used in TVs:
BBK LT1514S (Panel SVA150XG04), BBK LT1914S (Panel 19 inches 1440x900), BBK LT1915S (Panel HT190WG1-101).
The appearance of the power supply
Main features of the BBK LT1914S device:
Installed matrix (LCD-panel) 19 inches 1440x900.
The JSI-190411ROH inverter is used to power the backlight, controlled by the BIT3105 PWM controller. As power elements of the inverter, keys of the type MI3106 (so8) are used.
The necessary supply voltages for all nodes of the BBK LT1914S TV are generated by the JSI-190411 power module or its analogs using SG5841SZ (SO8) microcircuits.
MainBoard - the main board (motherboard) is an E-RSAG7.820.847A module, using the chips FLI8125, SST39VF088-70-4CEKE, MSP34XX, TDA1517 and others.
The DQ-6FT / W116H tuner provides television reception and channel tuning.
BBK LT1914S LCD TV with 19 ”LCD, 19” (48 cm) diagonal 16:10 aspect ratio. 400 cd / m² screen brightness is provided by CCFL (EEFL) fluorescent lamps. The ratio of maximum brightness to minimum (contrast) is 500: 1. It is possible to view images in high quality HD with a resolution of 1440x900 pixels in the standard of graphic decomposition 720p (HD Ready). The input high-frequency or video signal can be processed in analog systems PAL, SECAM, NTSC. Graphic processing and digital signal generation occurs in the standards 4 80i, 480p, 576i, 576p, 720p, 1080i.
The power of the sound system 3 W (2x1.5 W) provide two speakers. The audio processing system NICAM STEREO is used.
The external interface (communication with other devices) is supported by standard input and output connectors: antenna input (RF), AV, audio x2, S-Video, component, SCART, RGB, VGA, HDMI. An output for connecting headphones is provided. To connect a computer or laptop to this TV model, a VGA (D-Sub 15) connector is used on the TV case, this interface supports resolutions: 640x480, 800x600, 1024x768, 1360x768.
The power consumed by the TV in the operating mode from the network is 40 watts.
Overall dimensions: 493x479x198 mm.
TV Weight: 7 kg.
Attention! The 19-inch 1440x900 panel of the BBK LT1914S LCD TV is its most expensive component.
Avoid hitting the glass and exerting pressure on the screen to avoid permanent damage to the LCD panel!