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picree
Joined: 31 Mar 2006
Posts: 351
Location: Johnson City, TN
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| Posted: Fri Aug 17, 2007 2:45 am Post subject: Red tube brighter on one half-Barco 808-WITH PHOTO!! |
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BG808-I have tried to troubleshoot this without bothering the forum with simple questions but I'm out of ideas and think it's the tube. Interested in the experts opinion before I go shopping for a new tube or send this thing off to VDC for a rebuild.
Looking at the screen the left side of the red tube is brighter than the right side. So, at 30 IRE the red glow on the left side is obvious and certainly not correctable. At 80 IRE you can't tell. The red active area is no longer nice an uniform but sort of wavy and fades out to the right. I have ruled out the following components by swapping parts:
G2 board
Quad decoder/RGB Gain board
HV Splitter (swapped HV leads)
RGB output amp
Neckboard
Have I missed anything? Has anyone seen this before? If it is the tube what would be causing it? One of the coils on the neck? Focus coil?
It only recently started doing this. During a recent power-on the entire projector "glitched". The result was that all the G2's reset themselves to a very high level for no obvious reason. I quickly opened up the proj and turned the G2 pots to lower it back down. Never figured out what happened. Related?
Any help is greatly appreciated. Does anyone have a red 180DVB22 they might want to sell (maybe a 9/10)?
Curt
Edit-uploaded a photo that might help diagnose the problem. This is supposed to be a 10 IRE gray field. Any thoughts?
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picree
Joined: 31 Mar 2006
Posts: 351
Location: Johnson City, TN
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| Posted: Sat Aug 18, 2007 3:31 pm Post subject: |
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Bump.....
_________________
MAIN THEATER: (JVC RS2000; Yamaha UDP-LX500; Yamaha RX-V2400; Lumagen Radiance Pro, Vertex)
SECOND WII-ATER: (BG808; WII; Oppo 971H; Moome external box; BG-DVI transcoder; tse gamma box; Extron)
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Tom.W
Joined: 09 Mar 2006
Posts: 6635
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| Posted: Sat Aug 18, 2007 4:16 pm Post subject: |
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Try reversing the scan . Does the trouble move to the other side of the CRT face ? Don't think it's the CRT
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picree
Joined: 31 Mar 2006
Posts: 351
Location: Johnson City, TN
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| Posted: Sat Aug 18, 2007 4:28 pm Post subject: |
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Cool suggestion Tom! If I reverse the scan the bright area does indeed flip from the left to the right. Considering what I have swapped out already which component would you suspect?
_________________
MAIN THEATER: (JVC RS2000; Yamaha UDP-LX500; Yamaha RX-V2400; Lumagen Radiance Pro, Vertex)
SECOND WII-ATER: (BG808; WII; Oppo 971H; Moome external box; BG-DVI transcoder; tse gamma box; Extron)
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Tom.W
Joined: 09 Mar 2006
Posts: 6635
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| Posted: Sat Aug 18, 2007 4:31 pm Post subject: |
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Bad scan coil maybe but Iv'e never seen this type of problem before . Does it make any difference when you switch input ports ?
Last edited by Tom.W on Sat Aug 18, 2007 4:43 pm; edited 1 time in total
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Curt Palme
CRT Tech
Joined: 08 Mar 2006
Posts: 24396
Location: Langley, BC
TV/Projector: All of them!
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| Posted: Sat Aug 18, 2007 4:38 pm Post subject: |
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This has to be video or G2 related. I can't see it being a scan coil, you'd have massive linearity distortion, but I'll bet the grid is fine. This is a new one on me. I'm assuming the G and B are fine? try swapping the yellow wires going to the motherboard from the video output board between the R and G. If you take off the video output boards, you should have enough length. that's the video drive signal, and the green should then show the problem. That would eliminate the G2 and would narrow it down to a video problem.
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picree
Joined: 31 Mar 2006
Posts: 351
Location: Johnson City, TN
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| Posted: Sat Aug 18, 2007 5:03 pm Post subject: |
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The grid is fine (square, I mean)...G & B are fine. If I swap the video drive signal the problem does indeed go over to the green tube. This is good news as the red tube looks brand new w/ no wear and I didn't want to have to buy a new one...
So, a video problem?...I'll check the signal. Are there any suspect boards???
EDIT: Thanks for the help guys. Looks like it's something either in my tse gamma box or being amplified by it... Anyways, glad it wasn't a tube.
Thanks Tom & Curt
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Tom.W
Joined: 09 Mar 2006
Posts: 6635
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| Posted: Sat Aug 18, 2007 7:04 pm Post subject: |
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Who made tse's card for you . Bad solder joint or does it look like a failed component ?
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Curt Palme
CRT Tech
Joined: 08 Mar 2006
Posts: 24396
Location: Langley, BC
TV/Projector: All of them!
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| Posted: Sat Aug 18, 2007 8:22 pm Post subject: |
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Well thank gawd it was external, this problem inside of a Barco would have had me stumped..
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lucht
Guest
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| Posted: Sat Aug 18, 2007 8:26 pm Post subject: |
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Do you have instead of a 2nd analog R7621055 a R761876 on this place?
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picree
Joined: 31 Mar 2006
Posts: 351
Location: Johnson City, TN
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| Posted: Mon Aug 20, 2007 1:30 am Post subject: |
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| Tom.W wrote: | | Who made tse's card for you . Bad solder joint or does it look like a failed component ? |
I made my own tse card so therein may lie the problem...  
Well, I think that in the end the tse box was simply amplifying a problem that was coming from somewhere up the line or maybe a loose cable. I did connect/reconnect all the RGBHV cables in/out of the tse box/projector and the problem diminished significantly. However, it's still there. Then I bypassed the tse box but could still barely see it.
It's either coming from the Oppo DVD player via DVI (doubtful), the moome external transcoder, or the Extron (my bet). I know I have too many components on the signal line for the purists but the result is generally quite good. I'll have to swap out the Extron and see what happens (although it is a brand new one so we'll see).
| lucht wrote: | | Do you have instead of a 2nd analog R7621055 a R761876 on this place? |
No I have the R7621055. All of this is running through port 5 via RGBHV...
Thanks very much for help & guidance... 
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