Friday 10 April 2020

REPAIR / SERVICING TV AKIRA LCT-26CH01ST

Technical description and composition of the TV AKIRA LCT-26CH01ST, type of panel and applicable modules. The composition of the modules.
AKIRA
Model: LCT-26CH01ST / R
Chassis / Version: LS01
Panel: V270B1-L03 Rev. C1
Inverter (backlight): 1270B1-12A V270B1-L03 (INV 05) 6lamp
PWM Inverter: OZ964GN
Power Supply (PSU): FSP205-5E01
PWM Power: TEA1532A (PWM 8pin), UCC28051 (PFC), L6599D (PWM Resonant)
MOSFET Power: 112N50C3 (PFC), K3568
MainBoard: JUG7.820.015
IC MainBoard: M12L643322A-6T, AT24C64A, T5BS4-9999, SVP-CX32LF, 74HCT4052D
Tuner: JS-6H2 / 121
Technical Specifications LCT-26CH01ST
AKIRA LCT-26CH01ST
General recommendations for repairing TV LCD
Possible manifestations of defects
- The AKIRA LCT-26CH01ST TV does not turn on at all. There is no reaction to the remote control or to the control buttons from the front panel. Indicator lights do not light or flash.
Often in such cases, the FSP205-5E01 power module is faulty. It is necessary to measure its secondary output voltages, and if they are absent, check the health of the power switches (112N50C3 (PFC), K3568) 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 a short circuit in the elements of the primary circuit, the mains fuse usually breaks.
Mos-Fet keys used in switching power supplies usually fail due to a malfunction of other elements that can put it out of operation in key mode or provoke an excess of the maximum current or voltage. It can be supply, damper circuits, or elements of OOS (negative feedback) stabilization. The reason for the breakdown of the power key can be PWM (PWM) TEA1532A (PWM 8pin), UCC28051 (PFC), L6599D (PWM Resonant). It is checked only by replacement with a known good one.
- 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
The defect can be caused by problems in the nodes or elements of the backlight of the display, or in the power supply of the lamps or the inverter.After checking all the electrolytic capacitors of the filters that are involved in the power supply to the inverter, you must ring in its converter power keys for breakdown and secondary windings of transformers for an open.
If in diagnosing a malfunction, it is necessary to disable the inverter protection, there is a risk of failure of the power elements of the inverter, and special care is required during work, and after they are finished, it is necessary to restore the protection circuits for further safe operation of the TV by the owner in normal mode.
- The TV does not turn on, does not respond to the remote control. The indicator blinks or signals standby mode.
Repair or diagnostics of the JUG7.820.015 motherboard should begin by checking the stabilizers and power converters needed to power the microcircuits and matrix. If necessary, update or replace the software (software). Sophisticated MB board repair (SSB) is in some cases possible and practiced by repairmen. To do this, check and, if necessary, replace the elements M12L643322A-6T, AT24C64A, T5BS4-9999, SVP-CX32LF, 74HCT4052D. BGA chip malfunctions are usually easy to detect by warming up.
If there is no reception of television channels, but the TV works properly from external devices, first of all you need to check the voltage of the JS-6H2 / 121 tuner and update the software. The pulses from the I2C bus must be controlled with an oscilloscope.
Attention to users! Self-repair of the AKIRA LCT-26CH01ST TV without the appropriate qualifications and the necessary experience can lead to its complete non-repairability!


SCHEMATIC DIAGRAM  / SERVICE MANUAL   ------------------>   AKIRA LCT-26CH01ST


The appearance of the MainBoard JUG7.820.015 is shown in the figure below:
JUG7.820.015
JUG7.820.015 can be used on TVs:
AKAI LTA-32C904 (Panel V320B1-L04 Rev.C1), AKIRA LCT-26CH01ST /R (Panel V270B1-L03 Rev.C1).
The appearance of the power supply
Key Features of the AKIRA LCT-26CH01ST:
Installed matrix (LCD panel) V270B1-L03 Rev. C1.
To power the backlight, an inverter 1270B1-12A is used, it is controlled by the OZ964GN PWM controller.
The necessary supply voltages for all nodes of the TV AKIRA LCT-26CH01ST are generated by the FSP205-5E01 power supply module or its analogs using TEA1532A (PWM 8pin), UCC28051 (PFC), L6599D (PWM Resonant) microcircuits and 112N50C3 (PFC) type power switches, K3568.
MainBoard - the main board (motherboard) is a JUG7.820.015 module, with the use of chips M12L643322A-6T, AT24C64A, T5BS4-9999, SVP-CX32LF, 74HCT4052D and others.
The JS-6H2 / 121 tuner provides TV reception and channel tuning.
Additional technical information about the panel:
Brand: CMO
Model: V270B1-L03
Type: a-Si TFT-LCD, Panel
Diagonal size: 27.0 inch
Resolution: 1366x768, WXGA
Display Mode: Super MVA, Normally Black, Transmissive
Active Area: 596.259x335.232 mm
Surface: Antiglare (Haze 25%), Hard coating (3H)
Brightness: 500 cd / m²
Contrast Ratio: 1200: 1
Display Colors: 16.7M (8-bit), CIE1931 75%
Response Time: 6.5 (G to G)
Frequency: 60Hz
Lamp Type: 12 pcs CCFL Embedded (Inverter)
Signal Interface: LVDS (1 ch, 8-bit), 30 pins
Voltage: 5.0V

Trademark: AKIRA, Model: LCT-26CH01ST.
Short from TV: LCD, 26 ", 1366x768, 720p HD, sound: 10 watts.
The composition uses MainBoard JUG7.820.015 and the LCD panel (matrix) V270B1-L03 Rev. C1.
Power Supply Unit (PSU) FSP205-5E01 Power Supply.
AKIRA LCT-26CH01ST TV with a V270B1-L03 LCD, 26 "(66 cm) diagonal size in 16: 9 format. 550 cd / m² screen brightness is provided by CCFL (EEFL) lamps. Contrast - the ratio of maximum brightness to minimum is not less than 800: 1. It is possible to view in high quality HD at a resolution of 1366x768 pixels in 720p standard (HD Ready). The input high-frequency or video signal is decoded in PAL, SECAM, NTSC analog systems. Digital signal generation (graphic format) is performed in 480i, 480p standards , 576i, 576p, 720p, 1080i.
The power of the speaker system is 10 W (2x5 W). 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, RGB. A standard VGA (D-Sub 15) connector is used to connect a laptop or computer. This interface supports resolutions: 640x480, 800x600, 1024x768, 1360x768.
Overall dimensions: With stand 731x468x166 mm, Without stand 731x437x87 mm.
Attention! The AKIRA LCT-26CH01ST LCD TV panel V270B1-L03 Rev. C1 is its most expensive component.
Avoid hitting the glass and exerting pressure on the screen to avoid permanent damage to the LCD panel!