| Author |
Message |
danielparker
Joined: 23 Sep 2007
Posts: 27
|
| Posted: Fri Dec 02, 2011 10:01 am Post subject: Marquee 9500LC Blue dots / lines |
|
|
Hi,
I have recently noticed that on the odd occasion I end up with blue lines & dots appearing on the screen.
1) This occurs only in dark / black scenes (or at least, thats the only time they are noticeable)
2) They are source independent.. They occur even when there is no input on any source.
3) They are intermittent..
4) They only seam to affect the blue tube
5) Looking at the tube face, they are also occurring outside of the active area.
Image of blue tube: http://cdn.beercellar.com/misc/2.jpg (2.4mb)
Video of blue tube: http://cdn.beercellar.com/misc/2.MOV (27mb)
I have uploaded pictures of the tube faces as they show the problem better than a photo of the screen.
Here is and image of the red tube at the same time, not exhibiting the issue: http://cdn.beercellar.com/misc/3.jpg
Any suggestions please..
Daniel Parker
|
|
| Back to top |
|
 |
barclay66
Joined: 27 Jun 2011
Posts: 1304
Location: Germany
TV/Projector: Marquee 9500 Ultra
|
| Posted: Fri Dec 02, 2011 11:45 am Post subject: |
|
|
Hi,
To me this looks like some noise which is going into the blue channel of the video chain. First I would check all connections to the blue neckboard, especially those for ground. Next I would try to swap the neckboard with another color, let's say green. If the dots switch to green it could be a faulty neckboard. If they stay on blue it could be an issue with the VIM or the cabling going to the blue tube. I don't think it could be the tube itself, but maybe someone may prove i'm wrong...
Regards,
barclay66
|
|
| Back to top |
|
|
tse
Joined: 03 May 2006
Posts: 1014
Location: Sweatbucket, Fl.
|
| Posted: Fri Dec 02, 2011 9:57 pm Post subject: |
|
|
If you look at the front side of the blue neck card, near the video connector, you will see a couple of jumper wires. Pull them up, away from the PCB. They are part of the heater circuit and will radiate noise into the video if close to the input circuits. Carefully replace the G-2 wire if you take the cards off the tubes.
Scott
_________________
"Were we directed from Washington when to sow and when to reap, we would soon want bread."
Thomas Jefferson
|
|
| Back to top |
|
|
draganm
Joined: 08 Mar 2006
Posts: 8990
Location: Colorado
|
| Posted: Fri Dec 02, 2011 11:02 pm Post subject: |
|
|
| Quote: | | front side of the blue neck card, near the video connector, you will see a couple of jumper wires. Pull them up, away from the PCB. They are part of the heater circuit and will radiate noise into the video if close to the input circuits. |
Daniel if you find that that's the source of the noise I have a performance/modification package which moves those wires away from the video circuit and filters the line for a nice noise reduction on all 3 tubes.
|
|
| Back to top |
|
|
danielparker
Joined: 23 Sep 2007
Posts: 27
|
| Posted: Sat Dec 03, 2011 7:03 am Post subject: |
|
|
Thanks for the suggestions.. I will try to take a look tomorrow and report back.
Daniel
|
|
| Back to top |
|
|
danielparker
Joined: 23 Sep 2007
Posts: 27
|
| Posted: Mon Dec 05, 2011 10:36 am Post subject: |
|
|
OK.. Well I moved the two filament wires, and also used some deoxit on the mini rca cables, and other connection points on the VIM etc, and so far, I haven't seen the problem come back.. It might take a while before I can say it is fixed.. but so far, so good.
draganm - Is you modification a part of your 'Marquee HD mods'?
Thanks for your help.
Daniel
Last edited by danielparker on Mon Dec 05, 2011 3:07 pm; edited 1 time in total
|
|
| Back to top |
|
|
Nashou66
Joined: 12 Jan 2007
Posts: 16171
Location: West Seneca NY
|
|
| Back to top |
|
|
draganm
Joined: 08 Mar 2006
Posts: 8990
Location: Colorado
|
| Posted: Mon Dec 05, 2011 7:12 pm Post subject: |
|
|
| Nashou66 wrote: | Yep Drags does that in the VNB upgrade and adds some chokes on the lines. Nice simple mod .
Athanasios |
right, it's all part of the basic HD mod's package. Soon to be joined by the "super HDM" ? upgrade. Haven' thought of a name yet.
Those parts were ordered last night so possibly ready within a week but I will want to run the heck out of it before any sales.
|
|
| Back to top |
|
|
|
|
