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Repairing Samsung 153V LCD Keep an eye on With Dim Display Difficulty

Among the widespread troubles in Samsung 153v LCD Keep an eye on was screen dim. When you get closer towards the display and start to observe the display below dark environment you really could see the show but it was incredibly dim. If you ever press the front panel button, the on display screen show (OSD) would appeared and this evidence the primary board, driver board and LCD panel is functioning along with the challenge is within the inverter board. The functionality of inverter board would be to generate an ac wave from dc voltage to power up the lamps which was located in the leading and bottom of the LCD Observe. If the inverter board has complications it would not light up the lamps and what you could see only a dim show.

I nevertheless could recall when I 1st encountered these difficulties long time ago and due to lack of data, I could not solve it. I did get in touch with up my restore pals to asked about the solution but nobody in a position to give me an answer. Even should you surf the net for “Samsung 153V LCD Keep an eye on dim exhibit repair”, you’d not get it. On account of this I have to complete my own investigation to obtain the remedy and I’ve in no way quit. Winston Churchill when stated “Never, never, never give up”. I am releasing the remedy only to my loyal members or subscribers only-thanks for the support.

Let us begin now! As soon as the cover and the internal aluminum casing had been opened I found two bulged filter capacitors in the secondary side of switch mode power provide. The value was 470 and 1000 microfarad 25 volts. I noticed four extra electrolytic capacitors situated at the inverter board have changed coloration and also the value was 47 micro farad 25 volts. Browsing by way of the entire board with my ESR meter I discovered yet another capacitor faulty (220 uf twenty five volts) which was near the fuse (3amp). Because this capacitor was located in the exact same line using the fuse, I presumed that the fuse may give way too. True sufficient, checking the fuse with the ohmmeter disclosed that it’s got open circuit.

Now, the real challenge confronted by lots of electronic repairers who deals with this particular design was, soon after changing all the elements earlier mentioned the LCD Keep an eye on still wouldn’t work-it’s nonetheless dim! 1st you’ve to ask your self why the fuse blown? Could it be brought on by the defective capacitors or some thing shorted outside of the fuse line? The nearest circuit towards the fuse was the start off circuit that consisted of the pair of NPN and PNP digital transistor (4k7 +4k7 resistor built in to the transistor). Another LCD monitor developed utilised the mixture of C945 and A733 in commence circuit. From the way the part range for Samsung 153V begin circuit transistors were the A6J (PNP digital transistor) and the A8J (NPN digital transistor) as shown inside the image.

Often only these transistors have complications (shorted) that brought on the fuse to blow but in the above case both digital transistors are tested okay. Since each transistors were working, now the focus need to be within the 4 ic’s that generate the large voltage transformers given that the twelve volts voltage was supplying to every of those ic’s. These four ic’s have a lot of portion numbers and also the most widespread 1 that the manufacturer employed was 4532m. Some board utilised the AD4E10 and BBD3N13 part quantity. In the minute it really is quite hard to obtain the datasheet or technical specification for this range even in the web search.

Do you realize what’s inside these IC’s? It’s truly a pair of P-channel as well as a N-channel mosfet constructed into it. And do you know that it can be check having a meter? Certainly, if you ever utilize the Peak atlas part analyzer, it would prompt to you personally the consequence. From the outcome that which you get are N channel FET located at pin one (supply), pin two (gate), pin 7 & 8 (drain and both pins joint together internally). As for P channel FET, pin 3 (source), pin four (gate) and pin 5 & 6 (drain and each pins joint internally). In the over examination I discovered two of these ic’s have shorted. Changing these two shorted IC using the capacitors and fuse put the LCD Monitor back to life!

One far more issue I would like to share on this design was the inverter PWM IC BIT1305 was really robust and rarely gave trouble.

This BenQ T705 LCD Check features a common fault of screen shutdown after few you “On” for couple of seconds. The cause with the issue was in most cases a shorted one or two in the C5707 push pull transistors. Apart from the shorted transistor, one also needs to examine the tuning capacitor for substantial ESR value using the help of ESR meter. For those who don’t own 1, you possibly can use the digital capacitance meter to examine the capacitance value. Nevertheless, from my encounter, checking only the capacitance worth does not guarantee the capacitor is very good unless you verify it with ESR meter. The reason why I emphasis on checking this tuning capacitors was due to the fact the capacitors have a great failure price that may cause the C5707 transistor to go shorted. Additionally you have to observe the huge voltage transformer pins cautiously. I had arrive across very a number of shorted C5707 transistors brought on by dry joints in pins from the great voltage transformer.

On this case, as regular after I have confirmed that only two C5707 transistors shorted, I began to test the tuning capacitors and examine the pins of the large voltage transformer. Both the tuning capacitors found to become okay but there had been dry joints in the transformer pins. Clean solder was applied for the superior voltage transformer pins and I’m ready to “On” the LCD Keep track of. Guess what? The Watch has the identical symptom again that is display shutdown immediately after few seconds! I do not think it as most of the time it will certainly function as this is really a widespread fault!

I started to recheck the surrounding components that have connection for the C5707 transistors but found no faults in it. Analyzing the board a lot of times didn’t reveal any improper soldering employment. There have to be something which has gone wrong that had caused the LCD Check to shutdown. Deep in my heart I do not suspect backlights issue due to the fact the C5707 transistors shorted was caused by dry joints in the huge voltage transformer. Beside, the backlights had been quite reliable for this BenQ LCD Observe model.

Considering back again, I bought a new badge of C5707 transistors from my electronic suppliers not lengthy ago. The center pin (leg) is usually a bit shorter compared to other two as demonstrated in the photograph below. I thought to myself would it be this badge of transistors which have predicament producing the show shutdown immediately after couple of seconds? Certainly I can’t blindly suspect the transistors unless of course I’ve some proof of it. The acquiring starts………………

Testing the C5707 transistor with an analogue meter set to X 1 and also to X 10 K Ohm doesn’t appear like it’s got trouble. Comparing the result with an unique C5707 transistor did have some difference inside the X ten K Ohm variety however the studying is appropriate from my decades of experience in testing transistor. The only factor that I have not compared will be the Hfe studying. I used the famous Peak Atlas components analyzer to analyze both transistors and I could obviously see the major distinction in between the Hfe readings with the two transistors. The original C5707 transistor has Hfe worth of 379 even though the new badge in the C5707 transistor has Hfe value of 161! At final I discovered the reply!

I did tried replace the 4 C5707 transistors at 1 go using the new badge of transistors however the consequence was the identical. Setting up the transistors which have the Hfe reading of 350 to 400 solved the exhibit shutdown difficulty. This circuit search like it can only work using the exact same kind of transistor which has the fairly precise Hfe worth! That’s why for this kind of Observe circuit, lots of technicians hardly can locate a appropriate alternative. In other words, even if you could get the substitution transistor which have greater Volt, Amp and Watt but several Hfe value, you nonetheless will not be able to deliver the LCD Keep an eye on back to lifetime again. In the earlier mentioned test, this Keep an eye on circuit has voice out loud and crystal clear that it only have to have the identical part quantity using the exact same Hfe value unless of course you have some comparable transistor replacement specification that’s identical to the unique 1.

For my readers that are on this electronic repairing line, even though a number of you may not be within the LCD Observe repair, I wish you are going to soak up this information and facts and apply it within your area. Who understands 1 day you’d have confront the same predicament that I am dealing with and this article could simply assist you to to solve your trouble quick. Have a good and a blessed day!

If you ever really like the idea of being in a position to watch Tv anywhere you’re then a portable LCD watch is correct for you personally. They are not only created for viewing tv but countless consumers who obtain them enjoy the capability to accomplish so with portability. Becoming tiny and light, they are able to easily go into your bag and be carried anywhere.

A transportable LCD observe can save you from long and dull commutes about the train or bus, supplying entertainment to create time enjoyable, to not mention fly by. You’ve got the choice to flick by means of channels and watch normal Tv broadcasts and catch up on the most recent news or it is possible to even attach a portable DVD player to view films and well-liked Tv demonstrates.

If you are relaxing at a coffee house or at the park on your lunch break and do not fancy reading a book, it is possible to plug inside your headphones and appreciate a film rather. It’s the perfect approach to entertain your self on these breaks with little to complete. Portable monitors also serve like a backup when the primary tv at house is being utilised.

Children just enjoy to view Television and play video clip games, which is often a issue whenever a sports activities game or exhibit you would like to view is on. To save from headache it is just so much easier to consider out the portable LCD keep track of and see what you would like each time you need without getting the children scream at you.

Most portable LCD TVs may have a built in antenna however the alternative is to plug in a Television cable. As mentioned, the advantages of acquiring a transportable check just isn’t just restricted to viewing Television, you possibly can in reality link it for your personal pc giving you dual screen capability.

Having a dual exhibit enables you to perform numerous projects without having possessing to close windows to view other files. This means you’ll be able to depart windows open for example Skype so you can chat to your friends and surf the internet in the same time or maintain as much as date with the news though operating. There is unlimited ways you could use a secondary exhibit to improve productivity as well as satisfaction.

Portable LCD monitors may also be utilized to monitor safety methods. So if you are far from residence and you need to check that every little thing is ok, you can actually link your security camera method to your pc via the net and have eyes in your house every time you want. You may even use it as nanny cam to keep track of your children when away.

Plasma Vs LCD Vs LED TVs – What exactly are the Differences?

In the last ten many years, Television technology has state-of-the-art to a terrific extent and has brought in state of art technologies in providing the very best flat-screen TVs. Probably the most crucial feature from the technologies utilised has primarily concentrated about the dimension, resolution and compatibility and with this, within the final 5 to ten decades there has been a gradual alter in the choice and viewing expectations of many people.

The producers have now began to put in exceptional characteristics in their flat-screen Television types creating the product getting a distinctive benefit of complete film impact viewing along with outstanding sound technology. You’ll find diverse types of flat-screen TVs in the market these days, and as a way which you could determine among Plasma, LCD, and a LED Tv, you ought to know a little about the variations.

Overview of Plasma Television: The screen in a Plasma Television is made up of hundreds of thousands of small plasma cells, and to place it just, these cells emit light to make a total image on the display whenever a precise voltage is applied to them.

Plasma TVs offered now present larger display screen size than LCDs. The screen sizes of Plasma TVs that are commonly readily available in the marketplace contain, thirty inch, 42 inch, fifty inch and 63 inch versions, though the LCD TVs are limited to smaller display screen dimensions, which range from ten inch to 40 inch models. Presently bigger display measurements of far more than sixty inches are being created available within the marketplace. 1 favourable point is that, the LCD technologies is extra versatile, which allows broad variety of screen measurements to become developed.

Positive aspects on Plasma TVs:
- Plasma TVs are accessible in larger display display screen dimensions.
- Plasma has superior black amounts, and also the contrast ratio.
- Plasma TVs can be viewed from any angle, as long as the viewing angle is amongst 160 to 180 degrees. – Plasma TVs have best refreshing charge which captures every single detail in a quickly action scene.
- Plasma screen can display billions of colors, producing smooth gradations of shades, enhancing the image top quality to a great extent, creating the pictures life-like and reasonable, responding sharply to fast moving images.

Drawbacks of Plasma TVs:
- Plasma TVS do not perform as well at higher altitudes.
- Plasma TVs are far more susceptible to burn-in of static images.
- Plasma TVS are thicker than LCD TVs and therefore significantly heavier.
- Plasma TVs generate glare in brightly lit rooms though some advancement in technologies continues to be produced to proper this.

Overview of LCD TVs: LCD TVs have Liquid Crystal Displays, a technology which is observed becoming employed in pc monitors, cell phones, and at occasions are identified in digital camera screens. LCD screen was initial developed for pc monitors, and now using the application with the technologies in LCD TVs, they appear to become a little far better when you’re actively playing video games in your Television. On the other hand, the choice totally depends upon the user, since some such as the vivid hues in Plasma Tv, which arrives from its deep black amounts.

LCD panels work with liquid crystal remedy becoming sandwiched between two polarized glasses. When an electrical voltage is applied towards the liquid crystal, the crystals rotate, and this modifications the polarization of the light passing through them. A LCD panel doesn’t generate light by alone. It just filters or subtracts its back again light source to create an image around the screen.

Positive aspects of LCD TVs:
- LCD TVs have better longevity than the Plasma. The average life-span has been predicted as even more than thirty ages.
- The display of LCD TVs uses lower energy compared to Plasma TVs, but has much more usage than LED. – The display sizes of LCD TVs are on the market in many dimensions starting from computer keep an eye on screens to over sixty inches.

Negatives of LCD TVs:
- The Tv has a rather poor contrast level and responds slower to rapidly relocating images, creating a blur.
- The costs of LCD TVs are greater than the Plasma, and for the reason that of the demand and elevated production the prices are gradually falling.

Overview of LED TVs: The term ‘LED’ stands for Light Emitting Diode. It can be an electronic component which emits light when a particular voltage potential is applied to its terminals. Though the Television employing this technology is simply call LED Television, however the LED light supply is utilized because the TV’s backlight, although the Television screen is really LCD. Though some current Television models use CCFL (Cold Cathode Fluorescent Lamps), LED form of backlighting continues to be a far alot more efficient Television backlight method.

The Benefits of LED TVs are as follows:
- With LEDs because the backlighting source, the TVs have a far far better dynamic contrast stage than LCD TVs, since it uses a direct backlighting technologies.
- LED TVS are ultra thin as much as about an inch in thickness.
- The power usage of LED TVs are less than the LCD TVs currently on the market.
- Out from the flat display TVs offered within the marketplace today, LED TVs are regarded as to become most trustworthy.

The disadvantage is the fact that LED TVS are higher priced than LCD TVs, but prices are expected to come down with elevated production.

The earlier mentioned is an attempt to supply a basic conception regarding the differences in between the three technologies obtainable presently in flat-screen TVs which would help a purchaser to determine which Tv to purchase.