CurtPalme.com Home Theater Forum

[deewaan1]

Hey all! Got an issue with my blue tube on my Marquee 8500. I have a vertical line showing up on the right side of my displayed image on screen at all times and a light boxed area near center of the displayed image that can only be seen when the image is black. When I look in the tubes all look fine but the blue. There appears to be scan lines outside of the normal projected area when compared to the other tubes. And adjusting the blanking doesn't do anything to get rid of it. Am I losing my blue tube? Any suggestions on what to try to get rid of this if it is something I can fix? Thanks!

[draganm]

turn the blue G2 down a few clicks.

[deewaan1]

[deewaan1]

Here are some pics.

[Nashou66]

Look at the width adjustment coils on the hdm, are any broken? those are the paper tube's with a winding around them. When you say overscan on the proper display do you mean looking in to the tube? is tihs going over the side of the tube face?

Athanasios

[deewaan1]

[Nashou66]

Hmmm looks like something is wrong with you HDM maybe. do you have another HDM to swap out? dont let it go over the tube for long, and also 73 is too high I think for your G2, set contrast and brightness to 50 each and adjust the blues G2 till you just see the raster light up with a 0 ire pattern, then back off a click.

Athanasios

[1031]

This could come from Vim also, unplug VIM and swap R/G coax cables and see if problem follows to red.
Also that "faint line ........." Tech bulletin mod that includes 3x 1,5Mohm resistors to the VIM , can help with this. (if this problem is related to vim )

Edit: link to Tech bulletin-> http://www.curtpalme.com/docs/ElectrohomeMarqueeTechnicalBulletin_LineFix.pdf

[PaulB]

I think Jarmo has hit the nail on the head, by chance I've just been looking at this thread http://curtpalme.com/forum/viewtopic.php?t=5130&start=0

Half-way down the page, Gary's blue tube looks identical to the one deewan1 has posted above.

The thread linked above has some very good info on the line fix and a related issue caused by connecting a DVD player.

Well worth a read. Its a fix I've yet to do as I have the line on my 02 VIM.

[Nashou66]

I didnt see those Pics! Deewann and i posted at the same time so i missed them it does look like garys issue, whats your source? I still say 73 is way way to high for G2.

Athanasios

[deewaan1]

[Nashou66]

Some times following Tims greyscale method isn't always right. Do this for all tubes and then go from there,

Set brightness and Contrast to 50 and set you drive levels to Tim's settings
then put up an external 0 ire window and adjust G2 till you barely see the raster light up,
then put up the 10% ire window, you should see it also,
once you have the black level set with your G2's put up an external Gray scale ramp and set up
G2's like you normally would. If you still have to raise the G2 on the Blue that high the tube is shot i would say.

How long were you runing it at 81? over 70 to me is still a bit high and only needed towards the end of a tubes life.

Make sure you filament voltage is still 6.35.

Athanasios

[deewaan1]

[Nashou66]

Now I wonder if it's the HVPS . Do you have a spare or borrow one to test?


here is the way to check your voltages, courtesy of Tim Martin


Troubleshooting Marquee Video Problems Without A Scope

One does not always have the luxury of a dual trace scope on the road,
here are a few norms to test for if your Marquee has high voltage and
picture problems, like flashing, or no pix at all, or one color is weak:

Vim Mini Coax Levels, Unplugged From VNB:

With CONT of 40 and BRITE of 40, the tip of the mini coax feed
gives 110mv with internal stairstep, 255mv on white field.

Internal Pattern Sequence is 1) Hatch plus Dots,
2) Dots Only, 3) Stairstep, 4) Full White, 5) Source

G2 Values and Voltage, measured at tip of VNB R76:

G2 of 40 gives +375vdc
45 +415vdc
50 +462vdc
55 +510vdc
60 +555vdc
65 +600vdc
70 +646vdc

Fluke DVM dc limit is 655vdc and goes into alarm mode.

Brightness Control Line to VNBs, P13 Pin 8:

BRITE of 0 gives +2.02vdc
10 +1.59vdc
20 +1.19vdc
30 +0.81vdc
40 +0.37vdc
50 - 0.02vdc
60 -0.44vdc

We have observed Marquees with leaking glycol where this control
voltage was shorted to +5v on the MB and as a result the tubes shut
down for no apparent reason; you would think you had a bad VIM
or neckboard but it was not so.

Tim at E-Tech Systems 480 368 7434 http://www.etechvideo.com/

Athanasios

[deewaan1]

Here's an update of what I've tried. Still have the problem. I have borrowed and tried the HDM, Focus board, , VIM, LVPS, HVPS and CLM. I have also tried unplugging the ribbon cable to the Convergence board and all no fix. I tried unplugging the ribbon cable to the V board but then the tubes don't power up so that doesn't help. I was thinking about trying the HVPS splitter but thought I'd toss the question back to you guys for any other ideas. Anyone? Anyone? Bueller?

[Sparky015]

With your G2 that high on the blue, you will see that faint line on the right side unless you do that tech bulletin on the VIM.

http://www.curtpalme.com/docs/ElectrohomeMarqueeTechnicalBulletin_LineFix.pdf

I had the same thing, went away after doing this fix. Same thing goes for the "DOT" fix bulletin. if you look into your red tube, you will probably see a dot towards the bottom of the tube if this fix has not been done.

As far as the high G2, have you tried swapping VNBs with another tube to see if it follows?

Paul

[deewaan1]

[deewaan1]

Hi. Swapping the neck boards didn't change anything. And I did the mod and that didn't fix this problem either. The problem does seem worse though. It is as if I have two sets of scan lines on the tubes. One just offset and to the lower left of the other with the projector mounted on the ceiling. The second set is not controlled by anything such as blanking or convergence. Is is behind the controlled image. And it is right against the right edge of the tube face. when an image is projected through the projector it is displayed only on the controlled set.

[Nashou66]

Ok , Do you have another CLM to try? or have you ever cleaned the socketed chips on the CLM and the DPB? if Not id clean all those chips, and the connectors to each board . Also try removing the CMM board that is above the CLM(if floor mounted), its used to adjust contrast at different zones, sometimes a faulty board can cause issues.

Athanasios

[Curt Palme]

It really sounds like you've swapped over everything in the set. THe one question that hasn't been asked yet:

Does it do it without an input signal connected?

[Curt Palme]

It really sounds like you've swapped over everything in the set. THe one question that hasn't been asked yet:

Does it do it without an input signal connected?