Not certain if this problem is caused by the bulb, ballast, or something else entirely. When the set is first turned on (cold) there are very pronounced "shadow lines" which flicker a little and slant diagonally across the screen from the lower left to the upper right of the screen. It takes a while, but after the set has warmed up for 15 min or so, they pretty much disappear and are not noticable after that. The picture seems as bright as is ever was, so beginning to think it could be the ballast? The bands are not colored, just shadow like. I don't think it could be mirrors since the problem goes away after warm-up.
Is anyone familiar with this problem and can tell me the cause and repair needed?
Thanks
Just FYI The set is a Samsung HLN567WX from 2004. I've replaced the circuit board once, color wheel once and lamp a few times. Never replaced the ballast.
Forgot to add there are no error lights of any kind on the front of the set.
ewqdpwiw
Moderator: Angel
Re: Shadow lines across screen at start-up only
Hi DaveC
When did the problem start? after any of the replacements you mentioned?
When did the problem start? after any of the replacements you mentioned?
Last edited by Angel on Thu Apr 23, 2009 8:45 pm, edited 1 time in total.
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Re: Shadow lines across screen at start-up only
DaveC,
The noise you are referring to on startup is most likely caused by a failing Digital Board or a weak Power Supply. I think that the problem is caused by insufficient power or a cold solder on the SMGP (surface mount graphic processor) on the digital board. Once the TV warms up, the current runs more fluent.
Also, check your inputs.. Does this happen on all inputs? Try hitting the menu button on your remote immediately and see if the lines also appear over the menu screen or under... This is a good way to see if the problem is comming from the the digital board or the DMD board.
Let us know!
The noise you are referring to on startup is most likely caused by a failing Digital Board or a weak Power Supply. I think that the problem is caused by insufficient power or a cold solder on the SMGP (surface mount graphic processor) on the digital board. Once the TV warms up, the current runs more fluent.
Also, check your inputs.. Does this happen on all inputs? Try hitting the menu button on your remote immediately and see if the lines also appear over the menu screen or under... This is a good way to see if the problem is comming from the the digital board or the DMD board.
Let us know!
Re: Shadow lines across screen at start-up only
Thanks for the replies. I'll try changing between the menu and channel screen tomorrow morning and see what I can observe. I didn't mention any noise in my previous post but since it was mentioned and just to clear things up, there are no unusual/different sounds so I am thinking it is unlikely that the ballast is the cause. I can't remember the order of sounds, but there is the familiar click, the familair electrical charge sound and the chimes. It starts-up just fine and the picture appears, but there are those pronounced diagonal shadow lines until the set warms up, after which they are no longer visible?
The problem just began out of the blue, not after any changes. The set had been operating normally for probably a year or so after the digital module was replaced.
Are there any tests that can be done to identify the problem other than switching between the menu screen? I only have a multi-meter, nothing more sophisticated.
The problem just began out of the blue, not after any changes. The set had been operating normally for probably a year or so after the digital module was replaced.
Are there any tests that can be done to identify the problem other than switching between the menu screen? I only have a multi-meter, nothing more sophisticated.
Re: Shadow lines across screen at start-up only
BTW funny you mention the SMGP. I just had that problem on my sons XBOX 360, a well documented problem. I guess even though the Digital module is only 12 mos old or so it can fail, but I am thinking (hoping) it is something else although the cost on new units has come down a lot. Are there any ste-by-step instructions anyone can point to on changing out the Digital Unit? I found good instructions on the color wheel, but have not see the same on the Digital board. As I recall, the technician had to make a few adjustments after changing the board so not certain it is a DIY repair for that reason?
Re: Shadow lines across screen at start-up only
This morning when I turned the set on, I tried changing between the regular channel and the menu on the "cable" remote. The lines appeared the same on both. I then tried the Samsung remote menu and the lines appeared the same when navigating through the Samsung set-up menus etc..ovadoggvo wrote:DaveC,
Also, check your inputs.. Does this happen on all inputs? Try hitting the menu button on your remote immediately and see if the lines also appear over the menu screen or under... This is a good way to see if the problem is comming from the the digital board or the DMD board.
Let us know!
The set has been running for a few hours now and the lines have diminished, are more horizontal across the screen, but still there and around three lines per inch all across the screen, each line stretching the full length of the screen.
So ..does the menu to screen flipping point to either the PCB Digital Board, the DMD Panel or the Power supply?
I believe it was the DMD Panel that was replaced about a year ago P/N BP96-00249A.
I think the PCB Digial Board is BP94-00385A
Re: Shadow lines across screen at start-up only
Called my local Service company that replaced the DMD Board last July. He asked me to insert and play a DVD to see if the lines still showed. They did, and are now showing slightly even after the set has been running for hours, so getting worse. Does anyone know how playing a DVD helps isolate where the problem is (DMD, PCB Board, power supply???) ? The Service guy said he needed to research the issue and would get back to me.
Re: Shadow lines across screen at start-up only
The tech says it is the Digital PCB (Power Control Board) BP94-00395A
