CurtPalme.com Home Theater Forum

audvid · Joined: 14 May 2008 Posts: 25

I have a marquee 9800. Last factory build from Christie. 2001.

I am seeing vertical/diagonal white lines across the screen, shifting randomly.. and appearing and disappearing randomly. I see the lines more in the green tube than the other two but essentially, I see a white disturbance pattern of lines.

Some times, they disappear but they seem to be showing up more often, day by day.
I can post the tube images but I don't know how to do that.. I can email the images.
my email is audvid@ameritech.net

Suggestions please?

Thank you.

Nashou66 · Joined: 12 Jan 2007 Posts: 16171 Location: West Seneca NY

Hi Audvid, I would first clean the Chips on the CLM, especially IC U7 on the Deflection processor board(DPB).

use an IC chip puller, radio shack has them just ask. also pick up some De-Oxit cleaner while your there. I spray the De Oxit into a water bottle cap and then dip a tooth brush
into it and brush the contacts on the chips and the sockets. Also do the DPB's connectors tot he maine CLM boards.

Athanasios

audvid · Joined: 14 May 2008 Posts: 25

Thanks! Actually, I swapped the neck boards and the swapping made the problem go away.

the_maniac · Joined: 10 Jul 2009 Posts: 111 Location: Austria - Europe

oh i think i have the same problem, so you interchanged the neckboards and it was completely away ?

audvid · Joined: 14 May 2008 Posts: 25

So far, the problem has gone away.. Perhaps such lines are less visible in blue tube? I don't know but the problem did go away.. It might well have been a grounding issue but even as I was interchanging, I felt that the grounding was quite good before the interchange..

Nashou66 · Joined: 12 Jan 2007 Posts: 16171 Location: West Seneca NY

I forgot to tell you to check the two black wires that are on the VNB, they need to be away from the board. On new VNB's VDC elevates those up away from the board with a blob of hot glue. They have EMI noise that gets into the Video op Amp right near by.

Athanasios

draganm · Joined: 08 Mar 2006 Posts: 8990 Location: Colorado

there's actually a TSB which instructs to bend the 2 metal tabs on the VNB cage away from the board at 30 degree's. This pushes the Black tube grounding wires away from the circuit, I do it to every set of boards i work on. Make sure the big Black wires are attached to the correct location and that the 2 smal black wires are not smashd flat on the board

JustGreg · Joined: 07 Mar 2006 Posts: 3098 Location: Kenosha, WI

I think Mike P actually advocated moving those twin black wires near the mini RCA to the back of the board a long time ago. I haven't done it yet but it's on the list to do to my spares before installing.
Draganm...what were you denoting as CRAP...the cap?

draganm · Joined: 08 Mar 2006 Posts: 8990 Location: Colorado

Nashou66 · Joined: 12 Jan 2007 Posts: 16171 Location: West Seneca NY

mp20748 · Posted: Thu Dec 24, 2009 5:47 pm Post subject:

If it's the same faint white lines that I'm familiar with, they're on every marquee. At least everyone that has a good video chain and reasonably good setup.

They're what I call "radiated noise"

Good luck trying to clean that up.

It's usually not noticed if the drives and input signal level are where they should be. because with a weak drive signal on the tubes, the lines will be somewhat more noticeable and show more.

Everyone of the BEST CRT projectors ever made has some form of lines or other noise in the raster. G90, Barco 909 (Cine9) Marquee, NEC and any other one ever manufactured.

draganm · Joined: 08 Mar 2006 Posts: 8990 Location: Colorado

I really don't think this is H-sweep noise since it's intermittent and getting worse

Nashou66 · Joined: 12 Jan 2007 Posts: 16171 Location: West Seneca NY

I should have posted this earlier, its not the faint line on the edge, I know what your talking about Mike with a good setup, I have that on both longbows and only after i uped the scan rate and got the set up closer to perfect. Audvids issue is noise like a dirty chip onthe CLM or the VNB trademark wire to close to the op amp. or it might have been a bad G2 connection that was fixed after he swapped the boards around, here is his pic.

Athanasios