REPAIRING AND NOT THROWING AWAY

REPAIRING AND NOT THROWING AWAY

Richtige Fernseher haben Röhren!

Richtige Fernseher haben Röhren!

In Brief: On this site you will find pictures and technical information about Service Modes, Circuit Diagrams, Firmware Update procedure, Disassemble procedure, Universal remote control set-up codes, Troubleshooting and more....

If you go into the profession, you will obtain or have access to a variety of tech tips databases HERE IT IS Master Electronics Repair !.

These are an excellent investment where the saying: 'time-is-money' rules. However, to learn, you need to develop a general troubleshooting approach - a logical, methodical, method of narrowing down the problem. A tech tip database might suggest: 'Replace C536' for a particular symptom. This is good advice for a specific problem on one model. However, what you really want to understand is why C536 was the cause and how to pinpoint the culprit in general even if you don't have a service manual or schematic and your tech tip database doesn't have an entry for your sick TV or VCR.

While schematics are nice, you won't always have them or be able to justify the purchase for a one-of repair. Therefore, in many cases, some reverse engineering will be necessary. The time will be well spent since even if you don't see another instance of the same model in your entire lifetime, you will have learned something in the process that can be applied to other equipment problems.
As always, when you get stuck, checking out a tech-tips database may quickly identify your problem and solution.In that case, you can greatly simplify your troubleshooting or at least confirm a diagnosis before ordering parts.

Happy repairing!
Today, the West is headed for the abyss. For the ultimate fate of our disposable society is for that society itself to be disposed of. And this will happen sooner, rather than later.

How to use the site:
- If you landed here via any Search Engine, you will get what you searched for and you can search more using the search this blog feature provided by Google. You can visit more posts scrolling the left blog archive of all posts of the month/year,
or you can click on the main photo-page to start from the main page. Doing so it starts from the most recent post to the older post simple clicking on the Older Post button on the bottom of each page after reading , post after post.

You can even visit all posts, time to time, when reaching the bottom end of each page and click on the Older Post button.

- If you arrived here at the main page via bookmark you can visit all the site scrolling the left blog archive of all posts of the month/year pointing were you want , or more simple You can even visit all blog posts, from newer to older, clicking at the end of each bottom page on the Older Post button.
So you can see all the blog/site content surfing all pages in it.

- The search this blog feature provided by Google is a real search engine. If you're pointing particular things it will search IT for you; or you can place a brand name in the search query at your choice and visit all results page by page. It's useful since the content of the site is very large.

Note that if you don't find what you searched for, try it after a period of time; the site is a never ending job !

..............The bitterness of poor quality is remembered long after the sweetness of todays funny gadgets low price has faded from memory........ . . . . . .....
Don't forget the past, the end of the world is upon us! Pretty soon it will all turn to dust!

©2010, 2011, 2012, 2013, 2014 Frank Sharp - You do not have permission to copy photos and words from this blog, and any content may be never used it for auctions or commercial purposes, however feel free to post anything you see here with a courtesy link back, btw a link to the original post here , is mandatory.
All posts are presented here for informative, historical and educative purposes as applicable within fair use. NOTHING HERE IS FOR SALE !

Saturday 21 March 2020

REPAIR / SERVICING TV BBK LT4219HD

Technical description and composition of the BBK LT4219HD TV, panel type and applicable modules. The composition of the modules.
BBK
Model: LT4219HD
Chassis / Version: RSAG7
Panel: V420H1-L11
T-CON: V420H1-C07
Inverter (backlight): 1420B1-16A-Master, 1420B1-16A-Slave
Power Supply (PSU): RSAG7.820.1185 ver E
MainBoard: RSAG7.820.1410 / ROH VER.C
IC MainBoard: SPI Flash: EN25F80
Tuner: TDQ-6FT / W126H
Technical Specifications LT4219HD
BBK LT4219HD
General recommendations for repairing TV LCD
Possible malfunctions
- BBK LT4219HD TV does not turn on, does not respond to the remote control and control panel buttons, indicators do not light up and do not blink.
Most likely in this case, the main switching power supply (IIPS) RSAG7.820.1185 is faulty. It is necessary to measure its secondary output voltages, 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.
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 switch may be PWM (PWM). It is checked only by replacement with a known good one.
- There is no image, but there is sound and reaction to commands from the remote control. Or the image appears immediately after turning on and 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. After checking all the electrolytic capacitors of the filters that are involved in the power supply of the inverter, you should ring in its converter the power switches for breakdown and the secondary windings of the 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 indicator blinks or lights constantly, the TV does not turn on, does not respond to the remote control.
Repair or diagnostics of the RSAG7.820.1410 motherboard should begin by checking the stabilizers and power converters needed to power the microcircuit and matrix. If necessary, update or replace the software (software). When repairing an MB board, you need to check its components SPI Flash: EN25F80. Defective items should be replaced. If chips with BGA soldering technology are used, a problem in its implementation is detected by the local heating of the chip.
In the absence of tuning to the channels of on-air or cable television, you should make sure that the software is correct, as well as in accordance with the ratings of the supply voltage at the terminals of the TDQ-6FT / W126H tuner. It is also necessary to check the presence of pulses of data exchange between the tuner and the processor via the I2C bus using an oscilloscope.
Attention to users! Self-repair of the TV BBK LT4219HD without the appropriate qualifications and the necessary experience can lead to its complete non-repairability!
Service Manual with Schematic Diagram 54 pages of 2008 on the LT4217HD, LT4219HD, LT4221HD, LT4221HDU





The appearance of the MainBoard RSAG7.820.1037 is shown in the figure below:
RSAG7.820.1037
RSAG7.820.1037 can be used in TVs:
BBK LT2614S (Panel V260B1-L02), BBK LT3214S (Panel LC320W01 (SL)(A1)), BBK LT4214S (Panel LC420WX7 Sl A1), BBK LT3215S (Panel LC320WX3 (SL)(C1)), BBK LT4014S (Panel LTA400WT-L17), DAEWOO DLP-26H1C (Panel V260B1-L02).
Main features of the BBK LT4219HD device:
Installed matrix (LCD panel) V420H1-L11.
The matrix control uses the Timing Controller (T-CON) V420H1-C07.
To power the backlight used inverter 1420B1-16A-Master.
The formation of the necessary supply voltages for all nodes of the BBK LT4219HD TV is carried out by the RSAG7.820.1185 power module, or its analogs.
MainBoard - the main board (motherboard) is an RSAG7.820.1410 module, using SPI Flash chips: EN25F80 and others.
The TDQ-6FT / W126H tuner provides TV reception and channel tuning.
Additional technical information about the panel:
Brand: CMO
Model: V420H1-L11
Type: a-Si TFT-LCD, Panel
Diagonal size: 42 inch
Resolution: 1920x1080, FHD
Display Mode: Super MVA, Normally Black, Transmissive
Active Area: 930.24x523.26 mm
Surface: Antiglare
Brightness: 430 cd / m²
Contrast Ratio: 2000: 1
Display Colors: 16.7M (8-bit), CIE1931 72%
Response Time: 6.5 (G to G)
Frequency: 60Hz
Lamp Type: 16 pcs CCFL Embedded (Inverter)
Signal Interface: LVDS (2 ch, 8-bit), 51 pins
Voltage: 12.0V

BBK LT4219HD LCD TV with V420H1-L11 LCD, 42 "(106 cm) diagonal display in 16: 9 format. 400 cd / m² screen brightness is provided by CCFL (EEFL) fluorescent lamps. Maximum brightness to minimum ratio (contrast) ) is 800: 1. The design and technical capabilities of the TV provide for viewing broadcasts and films in high quality HD at a resolution of 1920x1080 pixels in graphic decomposition according to the standard 1080p (Full HD). The input high-frequency or video signal can be processed in analog systems PAL, SECAM, NTSC . Graphic I process and generate the digital signal in the standards 480i, 480p, 576i, 576p, 720p, 1080i, 1080p. Stereo sound is realized by two built-in 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 x4, S-Video, component x2, SCART x2, RGB, VGA, HDMI x2. 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, 1920x1080.
The power consumed by the TV in the operating mode from the network is 250 watts.
Overall dimensions: 1028x736x310 mm.
The mass of the TV: 27 kg.
Attention! The BBK LT4219HD LCD TV panel V420H1-L11 is its most expensive component.
Avoid hitting the glass and exerting pressure on the screen to avoid permanent damage to the LCD panel!
Posted By: FRANK at 08:03
TAG: , , , ,