philips lcd shadow on half of the screen??

[buncey]

im getting a Philips 42PFL5603D lcd in tommorow apparently sound perfect and the picture is on ok but there is a shadow covering half of the screen.

would a faulty master or slave invertor cause this??


as from what i have seen if master or slave is faulty theres useual no picture.

anyone have any ideas,

[gabax]

im getting a Philips 42PFL5603D lcd in tommorow apparently sound perfect and the picture is on ok but there is a shadow covering half of the screen.



CHECK FOR POOR CONNECTION ON ONE OF OR MORE OF THE TUBES

[buncey]

ok thanks gabax.

are the tubes easy to get to? can they be changed or repaired?

also do you not think this could be a invertor problem??

[Contrast John]

Hi buncey
Have had a similar fault on 42 inch Philips where replacing the master and slave inverter boards (available from CHS) cured the problem. Picture ranged from completely dark at one side to almost full brightness at the other side. Not a cheap fix though and a big gamble to find out! Other possibilities are the ccfl tubes and/or their connections. Not had to strip one yet so unsure of the degree of difficulty.
Regards
John.

[buncey]

thanks Contrast John.

on inspection seems the invertor s are built into the psu  

the psu in question is PSU - DPS-279CP A

i have noticed the 2 small blue ceramic caps have run hot as the board has tuned a brown color and noticed 1 lead on the underside on one of the blue ceramic caps marked in pic had a dry joint where it must have run hot and melted solder i reflowed but made no difference.

i have also noticed there seems like a buzzing sound comming from a small area on the board, i have marked the area in photo. the transistors on the heatsink tested fine.

i cant see any dry joints in this area.


any ideas??

thankyou

[Turnip]

Hi Buncey,

Great piccy - some of us love 'em.

This is a 42 inch set with usually dozens of invertor transformers - can't see too many on that combined PS/Invertor , must be LED, 42Cm,  or you're pulling our lariats - Chris

[buncey]

hi chris the set in question is a 42PFL5603D which i believe is not a led set.

[Turnip]

Hi Buncey,

Know that, but you were initially talking dual invertors then composite Power/Invertor - bit daft on a 42 inch unless lit from either LEDs or another solar system - just a thought, love SF meself  - Chris

[buncey]

yes chris i was bit puzzled too when i opened set to find the Power/Invertor are one unit as i have found most philips have seperate m/s invertors 

i cant see any faulty components so might just be the main invertor, looks like i will need to order a new board.

as when you power up set you get a buzzing on psu and this reflects the picture are you can see the picture flickering.

[Contrast John]

Hi buncey
Given the price of a replacement psu/inverter (around £200 from CHS) it sounds like its time to dismantle the screen and have a look. Think this may be a model with a couple of pcbs out of sight driving the tubes. It might also be worth checking the ccfl tube holders for poor contacts.
Best of Luck
John.

[Turnip]

Hi Buncey,

But there's now't on that power board that looks like an invertor - hoping that Our Sparky will now dive in with more 'Midlander sense' - never get it me'self - well it's always in lower case  - Chris.

Hi - CJ, you beat me to it - Real Hero - Chris.

[sparky]

hi
if screen made by sony or samsung if so screen faulty
stock fault
dave

[buncey]

no the screen is made by Optronics.
im still convinced its somethink to do with the power board as i have disconnected both invertor connectors and the power board still buzzes and shuts down tv. the tv still acts the same with both connectors disconnected the same as when they are connected so im pretty sure its the main psu board related fault.
so i have ordered another board.

[floapa311]

modify master /slave inverter Lg

[Turnip]

Hi floapa311

Nice one - thanks - Chris.