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 !

Friday 20 March 2020

REPAIR / SERVICING TV BBK LT2008S

Technical description and composition of the BBK LT2008S TV, panel type and applicable modules. The composition of the modules.
BBK
Model: LT2008S
Panel: 20 inch
Inverter (backlight): BL2006001
PWM Inverter: BIT3106A (30)
MOSFET Inverter: AO4411 (8), AO4404 (8)
Power Supply (PSU): 52008-2 ver: L050818 V2.2
PWM Power: TOP249 (7)
MainBoard: 11703K-0
IC MainBoard: 92TL95D7T1 STV8216 L4950TS
Tuner: JS-6B2 / 121
Control: LT2008S approach LT117-02
Technical specifications LT2008S
BBK LT2008S
General recommendations for repairing TV LCD
Possible malfunctions
- The BBK LT2008S TV does not turn on and does not show any signs of operability at all. There is no reaction to either the remote control or the front panel control buttons.
In most of these cases, the 52008-2 main switching power supply 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. PWM chip TOP249 (7) can also be the cause of 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 indicator blinks or lights constantly, the TV does not turn on, does not respond to the remote control.
Repair or diagnostics of the 11703K-0 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 must check its components 92TL95D7T1 STV8216 L4950TS. Defective items should be replaced. If chips with BGA soldering technology are used, a problem in its implementation is detected by the method of local heating of the chip.
Before changing the tuner JS-6B2 / 121, if it is not possible to tune to television channels, make sure that there are supply voltages that must be measured at the corresponding terminals of the tuner and check the software for correctness. The pulses of the data exchange of the tuner with the processor can be controlled by an oscilloscope
Once again, we remind TV users: you should not make attempts to repair it yourself without the appropriate knowledge, experience and the necessary qualifications! Entrust repair to professionals with sufficient experience in the field of repair of electronic equipment.



Main features of the BBK LT2008S device:
Installed matrix (LCD-panel) 20 inches.
The BL2006001 inverter is used to power the backlight lamps; it is controlled by the BIT3106A PWM controller (30). As power elements of the inverter, keys of the type AO4411 (8), AO4404 (8) are used.
The necessary supply voltages for all nodes of the BBK LT2008S TV are generated by the 52008-2 power module or its analogs using TOP249 microcircuits (7).
MainBoard - the main board (motherboard) is a 11703K-0 module, using 92TL95D7T1 STV8216 L4950TS chips and others.
The JS-6B2 / 121 tuner provides television reception and channel tuning.


BBK LT2008S LCD TV with 20 ”LCD, 20” diagonal 4: 3 format. Screen brightness of 500 cd / m² is ensured by backlighting with CCFL (EEFL) fluorescent lamps. The ratio of maximum brightness to minimum (contrast) is 500: 1. 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 480i, 480p, 576i, 576p. 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 x3, S-Video, SCART, RGB, VGA. 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.
The power consumed by the TV in the operating mode from the network is 60 watts.
Overall dimensions: 620x450x202 mm.
TV Weight: 9.8 kg.
Attention! The 20-inch panel of the BBK LT2008S 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!