Dark picture with no other visible symptoms..
Moderator: Angel
Forum rules
Dark picture with no other visible symptoms..
I have a HLS5086WX/XAA. We purchased it in January 2007. We've never had any problems at all. Recently, the screen progressively has gotten darker. I tried to "brighten" it, but it appears to not make any difference. I stopped at Bestbuy, and the salesman said it could be the bulb. I haven't heard any nouses whatsoever other than the cooling fan and that sounds like it allways has. Any advise would be appreciated... Thanks!!
-
ChubbsTech
- TV Wizard
- Posts: 404
- Joined: Thu Feb 18, 2010 12:53 am
- Location: Santa Ana Ca.
Re: Dark picture with no other visible symptoms..
Hello kornfed.
Let me fill you in on how the DLP lamps like the one in your Samsung TV work.
First of all there are UHP ( ultra high performance lamps) that produce a light brighter than the sun. These lamps do not have a metal filament in the middle; they have a thin glass probe that contains mercury gas. It is inserted from the top terminal of the lamp, there is also a metal cable coming from the side terminal that to the naked eye might look that is completing a closed circuit… well its not! On the lamp there will be printed a 1.0 or a 1.3 which indicates the amount of millimeters that separate the middle glass probe from the side metal cable.
Normally when the lamp nears its final hours it either the picture will get gradually dimmer until its pitch black because its running out of mercury gas, or you’ll hear a loud pop and the lamp will implode doe to the complete absence of mercury gas creating and electric spark in the arc.
In other words (in my personal opinion) it’s very probable that you just need to replace the lamp and that’s it.
Good luck.
Let me fill you in on how the DLP lamps like the one in your Samsung TV work.
First of all there are UHP ( ultra high performance lamps) that produce a light brighter than the sun. These lamps do not have a metal filament in the middle; they have a thin glass probe that contains mercury gas. It is inserted from the top terminal of the lamp, there is also a metal cable coming from the side terminal that to the naked eye might look that is completing a closed circuit… well its not! On the lamp there will be printed a 1.0 or a 1.3 which indicates the amount of millimeters that separate the middle glass probe from the side metal cable.
Normally when the lamp nears its final hours it either the picture will get gradually dimmer until its pitch black because its running out of mercury gas, or you’ll hear a loud pop and the lamp will implode doe to the complete absence of mercury gas creating and electric spark in the arc.
In other words (in my personal opinion) it’s very probable that you just need to replace the lamp and that’s it.
Good luck.
- Attachments
-
- DSC00051.JPG (50.2 KiB) Viewed 8933 times
Re: Dark picture with no other visible symptoms..
I experienced the same situation. I replaced the bulb but picture was still dark. Replaced the ballast and it was like having a brand new TV.
-
ChubbsTech
- TV Wizard
- Posts: 404
- Joined: Thu Feb 18, 2010 12:53 am
- Location: Santa Ana Ca.
Re: Dark picture with no other visible symptoms..
Hello, Kentb53.
You are right, some times when the lamp goes out (especially when it implodes) it also takes the ballast with it. Let me explain in more detail.
First of all current is measured in amperes I.
Current (I) is a result of the amount of potential difference (volts) divided by the resistance (ohms). I = V / R.
So the less current there is the more voltage it allows resulting in more current going trough the circuit.
In this case that circuit is the ballast and lamp.
So when the lamp runs out of gas, the current doesn’t have anything to burn so it goes directly to the arc gap creating a very low resistance, and allowing a high amount of voltage. So now the ballast is sending a very high amount of current until it surpasses the capabilities of the materials until the melt or fry up.
Now the moral of the story is if you want to know what part you need replacing, first replace the lamp, if that doesn’t work (same symptoms) replace the ballast.
Good luck.
You are right, some times when the lamp goes out (especially when it implodes) it also takes the ballast with it. Let me explain in more detail.
First of all current is measured in amperes I.
Current (I) is a result of the amount of potential difference (volts) divided by the resistance (ohms). I = V / R.
So the less current there is the more voltage it allows resulting in more current going trough the circuit.
In this case that circuit is the ballast and lamp.
So when the lamp runs out of gas, the current doesn’t have anything to burn so it goes directly to the arc gap creating a very low resistance, and allowing a high amount of voltage. So now the ballast is sending a very high amount of current until it surpasses the capabilities of the materials until the melt or fry up.
Now the moral of the story is if you want to know what part you need replacing, first replace the lamp, if that doesn’t work (same symptoms) replace the ballast.
Good luck.
Re: Dark picture with no other visible symptoms..
Thanks for the replies and info!
I think I will go ahead and replace the bulb 1st and see if that will work. Then on to the ballast if the same system persists. Do you think replacing them at the same time would be best? Since I am having to order the parts any way, I was thinking of ordering them both just to make sure I have the ballast on hand in case it needs replaced as well. Thanks again!!!
I think I will go ahead and replace the bulb 1st and see if that will work. Then on to the ballast if the same system persists. Do you think replacing them at the same time would be best? Since I am having to order the parts any way, I was thinking of ordering them both just to make sure I have the ballast on hand in case it needs replaced as well. Thanks again!!!