Technical description and composition of the SUPRA STV-LC3742 TV, panel type and modules used. The composition of the modules.SUPRA
Model: STV-LC3742
Chassis / Version: LC- (26-37) HU26S
Panel: 37 inch
MainBoard: 782.GHU25-010D
IC MainBoard: MST9E88L-LF HEF4052 PI5V330
Tuner: TDQ-6F6 / W124X
STV-LC3742 Specifications
SUPRA STV-LC3742
General recommendations for TV LCD repair
SUPRA TV made on the LC- (26-37) HU26S chassis, like many other electronic devices, it is advisable to start repairing by inspecting all external and internal elements. Specific external damage to some elements can sometimes indicate further actions to determine the malfunction of the TV and localize the defect before starting the necessary measurements. Electrolytic capacitors of filters with a swollen case, as well as ring cracks formed in the soldering of the leads of heating elements or a layer of coal on burned out resistors sometimes prompt the repairman about the causes of the malfunction and the possible consequences.
In the case when the STV-LC3742 does not turn on, does not respond to the remote control and front panel buttons, does not blink the lights and does not show any signs of operability, the power module is probably faulty in this case. If it is working properly with such manifestations, it is necessary to check the processor power regulator (converter) on the motherboard. When repairing the power supply, it is advisable to start diagnostics with checking the mains fuse and electrolytic capacitors of the filters of the converter's secondary rectifiers. In the event of a break in the fuse, the cause should be sought in the power semiconductor elements of the pulse converter of the main power supply unit. It is necessary first of all to check the diodes of the rectifier bridge of the mains voltage and the power switch (s) of the converter.
If a breakdown of the power switch is detected, it should be remembered that in a switching power supply (SMPS) it does not fail by itself without reasons that should be looked for by checking other elements of the primary circuit - electrolytic capacitors, a PWM controller, which can only be checked replacement, as well as other semiconductor elements (diodes, transistors, zener diodes).
If SUPRA STV-LC3742 has no picture, but there is sound and the TV is controlled from the remote control, a malfunction in the display backlight units is likely. The lamps or the power converter - inverter may be faulty. Often in such cases, when the TV is turned on, an image appears and immediately disappears. First of all, it is necessary to make sure that the electrolytic capacitors of the rectifier filter supplying the inverter are in good working order, and check the LCD lamps by connecting external and known good diagnostics to the connectors.
Often attempts to repair the inverter are complicated by the fact that the diagnosis of a malfunction is complicated by the work of its protection, which is designed to turn off the inverter in emergency modes - when lamps are depressurized, breaks or short circuits in high-voltage connections and other emergency situations. Blocking protection for localizing a defect is popular among repairmen.
On the 782.GHU25-010D motherboard, in the event of a malfunction, you should first check the operability of all stabilizers or power converters of microcircuits and, if necessary, update the software (software). In some cases it is necessary to check or replace (if necessary) elements of the MB (SSB) board - MST9E88L-LF, HEF4052, PI5V330, tuner TDQ-6F6 / W124X. In cases where a BGA processor is used, its malfunction is usually detected by the local warm-up method.
Attention! Users and owners of STV-LC3742 TVs who do not have the appropriate qualifications, knowledge and experience are strongly discouraged from attempting to repair themselves in order to avoid negative consequences that may lead to the complete non-repairability of the device.
DOWNLOAD SCHEMATIC DIAGRAM / SERVICE MANUAL ------------------> SUPRA STV-LC3742 chassis: LC-(26-37)HU26S
The appearance of the MainBoard ST6369IV-E1C is shown in the figure below:ST6369IV-E1C
ST6369IV-E1C can be used in TVs:
SUPRA STV-LC50ST900FL (Panel HK500WLEDM-AHA7H), SUPRA STV-LC40ST900FL (Panel V400HJ6-PE1).
Main features of SUPRA STV-LC3742 device:
Installed matrix (LCD-panel) 37 inches.
The necessary supply voltages for all nodes of the SUPRA STV-LC3742 TV are provided by a switching power supply.
MainBoard - the main board (motherboard) is a 782.GHU25-010D module, using MST9E88L-LF HEF4052 PI5V330 chips and others.
The TDQ-6F6 / W124X tuner provides reception of television programs and tuning to channels.
LCD TV SUPRA STV-LC3742 with LCD, 37 "(94 cm) in 16: 9 format. The brightness of the screen is 500 cd / m², backlit by CCFL (EEFL) fluorescent lamps. Contrast - the ratio of maximum to minimum brightness is 1200: 1. It is possible to view broadcasts and films and images in high quality HD at a resolution of 1366x768 pixels in the standard graphic decomposition of 720p (HD Ready). Input high-frequency or video signal is decoded in analog systems PAL, SECAM, NTSC. Graphic processing and digital signal formation occurs in standards 480i, 480p, 576i, 576p, 720p, 1080i.
Speaker power 16 W (2x8 W) is provided by two speakers. The NICAM STEREO audio processing system is used.
External interface (communication with other devices) is supported by standard input and output connectors: antenna input (RF), AV, S-Video, component, SCART x2, RGB, HDMI. A headphone output is provided. To connect a computer or laptop to this TV model, use the VGA (D-Sub 15) connector on the TV case, this interface supports resolutions: 640x480, 800x600, 1024x768, 1360x768.
Dimensions: With stand 876x653x180 mm, Without stand 464x390x80 mm.
Attention! The SUPRA STV-LC3742 LCD TV panel is the most expensive component.
Avoid hitting the glass and putting pressure on the screen surface to avoid irreversible damage to the LCD panel!