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Service manual for Sony KLV-L32M1 TV wanted?

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For Test you can use old LCD monitor inverter board for testing as i can use broken l.c.d panel monitor circuit board as a C.C.F.L tester.
You can got it from scrape of l.c.d monitors.

---------- Post added at 01:59 ---------- Previous post was at 01:59 ----------

For Test you can use old LCD monitor inverter board for testing as i can use broken l.c.d panel monitor circuit board as a C.C.F.L tester.
You can got it from scrape of l.c.d monitors.
 

Thank you Imran, however I do not have a collection of old tv's to do this.

Tpetar, I do not have the led facilities available either, I am sure that I would also have to do something about the inverter talking to the processor too
so not as simple as a swap IMO.

How many CCFL tubes is this tv likely to have?
 

Sixteen CCFL tubes…
Have you tried to modify the old inverter board, set 'IND' = pin 39 on OZ976 to high level (disconnect from GND and re-connect to Vdd), in order to test how many lamps are still usable?
For more details post some PCB inverter images near to the OZ976 integrated circuit area.
 


imran99 said:
Its hard to convert like big LCD screens back-light system and remember one thing that you can not build your self controlled Inverter for L.E.D"s .
Click to expand...

LED dont use inverters, they dont need high voltage to operate like CFL, they works on few volts. Only if you put higher number of LED in serie you need higher voltage, that can be easy job.

May opinion is that LCD with CFL is history. CFL life time is bad.

LED controllers can be made very nicely controlled *could I say can be made in garage *. There are tons and tons of LED controllers on markets, DIY circuits,.... you can find on Internet DIY project for inteligent monitoring picture on tv and automaticly controlling brightness of LEDs.

When I take my LED tv from market, few days after that, I open and research design of device, and I put new software for newer video codec.... this is not soo high tech. We will see what will be with UltraHD :wink:
 
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tpetar said:
LED dont use inverters, they dont need high voltage to operate like CFL, they works on few volts. Only if you put higher number of LED in serie you need higher voltage, that can be easy job.

May opinion is that LCD with CFL is history. CFL life time is bad.

LED controllers can be made very nicely controlled *could I say can be made in garage *. There are tons and tons of LED controllers on markets, DIY circuits,.... you can find on Internet DIY project for inteligent monitoring picture on tv and automaticly controlling brightness of LEDs.

When I take my LED tv from market, few days after that, I open and research design of device, and I put new software for newer video codec.... this is not soo high tech. We will see what will be with UltraHD :wink:
Click to expand...


First you may need to update your self,In big Screen L.E.D TVs Like L.G 42LH90 have to controlled L.E.D"s from Inverter Circuit from 27.5 volts :)
I let you know that i am working on E.book of L.C.D and L.E.D T.v Repair and i have good source of information topic like that.
Now i told you more than that L.E.D T.v have some problems when Fails separately as back lights and creates strange problems when you viewing the video.
 

First you may need to update your self,In big Screen L.E.D TVs Like L.G 42LH90 have to controlled L.E.D"s from Inverter Circuit from 27.5 volts :)
Click to expand...
Yes, I agree, but CCFL dont work at 27V, CCFL need higher voltage. LED can work on lower voltage few volts, to to higher voltage when put in serie. Also CCFL inverter needs trafo, for LED there is lots of dedicated IC for LED driving as applications without trafo, or with using simple choke. Of course I speak in DIY variants, to convert LCD to LED.
 
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Life L.E.D VS CCFL

This is still an iffy subject but finally some light was shed when I did more research. I found something incredible. LED's offer the same life expectancy then CCFL's for the most part in LCDs. Keep in mind these life expectancies are for different applications not just LCD's, although I did manage to get some numbers)
CCFL life expectancy: 8,000-100,000 (25,000-75,000 appear to be common life expectancy in LCD's, I found no reference to 100,000 hour CCFL's used in LCD's)
LED Life expectancy (Dependant on color): 25,000-100,000 (50,000 hours is the common life expectancy in most applications** I found no reference to 100,000 hour LED's used in LCD's just claims that LED's "can" have life expectancy of 100,000 hours)
Keep in mind however LED's are subject to failing from heat, while CCFL do not.

**However life expectancy ranges from white, red, blue, etc. Red has the worst life expectancy, just how much worse I could not find however most sources say it's substantially worse.

Verdict: This is a very complex verdict. While I was able to pull up numbers I also found a lot of sources' resentment to LED manufacturers with their documentation/claims. Most criticized them for not:
* Specifying when the LED was considered dead (efficiency loss)- This is a major factor in expectancy. A few manufacturers answered claiming at 50% luminance loss was the LED considered "dead". The results showed 50,000 20,000 hours *I misread*. It would appear life expectancy varies greatly from manufacturer to manufacturer, its apparent to sources that luminance loss percentage was going to vary.
* Specifying LED's used (White, red, etc)
* At least publishing documentation etc. So far no publication
 

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