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Marquee with intermittent horizontal scan problem

5K views 47 replies 12 participants last post by  draganm 
#1 ·
My 9501 has developed an intermittent problem with the horizontal scan stability, see photo. For the first 30 minutes of use the picture is normal, but then suddenly the horizontal scan becomes unstable. The photo shows the test pattern but the effect is independent of input. The photo also has some artifacts, the oscillation is down the whole screen, largest at the top reducing down the screen. If I don't turn it off, sometimes a protection circuit trips and it powers down then comes back up. If I turn it off for a few seconds then back on, it works OK for another 5 minutes before the problem comes back. I'm assuming the problem is either a bad connector contact or a dry joint. I pulled most the boards and sprayed contact cleaner on all connectors including the daughter board on the horizontal deflection board, and checked all IC's were seated OK, but no change. I re-soldered the joints of all power components, coils, relays etc on the horizontal board, but still no change. Now I'm running out of idea's. Since all colors are affected, I'm assuming the problem is before the horizontal coil driver circuits. The contact cleaner I'm using is only a cleaner/degreaser, I'm trying to get hold of a de-oxidizer.

Has anyone seen this problem before or could point me in the right direction?
 
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#2 ·
Clean the U7 chip on the Deflection Processor board. That is the on the Control Logic Module(CLM). The board with all the LED's on the back of the Projector.


Its best to remove and clean all the chips on the CLM and daughter boards with DeOxit cleaner and then followed by the protectant. I bet that fixes it.


Athanasios
 
#3 ·
I have seen exactly this problem, but haven't solved it yet. I had one here about a month ago that did that too, but I swapped the HDM, and it's still here on the bench, I haven't worked on it yet. Try the cleaning, but on mine it was a bad HDM. I can fix yours if it turns out to be that..
 
#8 ·
Thanks for the idea's but after changing q501, c50, r23 and d3 and re-soldered all the joints on the HDM including the daughter board the problem is still there. The problem is temperature related, if the air con in the room is running, the problem does not occur, which still makes me think its a dry joint or bad connector. Curt, I know your problem was on the HDM board, but since the fixes I've tried haven't improved or worsened things, I'm thinking the it might be on the CLM board. Any suggestions?
 
#9 ·
At this point, you either need to send boards out for repair, or get spare boards to swap. I still think it's on the HDM.
 
#10 ·

Quote:
Originally Posted by Curt Palme /forum/post/19134885


I still think it's on the HDM.

Edit: yes most certainly an HDM heat issue.

I'm having this problem with a machine after doing the HD mod's, 2000 vintage 9500Lc ultra. After doing the work, replacing all capacitors, re-flowing the big transistors, etc. I Ran the boards here for 12 hours at 1080P, everything looked perfect. Customer reports oscillation after 2 of viewing. Problem disappears if you switch from short retrace to long.

I now have the HDM back + CLM (which I didn't work on). Tested CLM for over 4 hours and HDM for 12 hours at 1080P and saw nothing wrong.

Also had customer disconnect CVA, FGM, and Stig amp to verfy it wasn't it. the only thing I haven't re-tested here is the VDM.

triplington can you please verify that all 3 belly fans are working in your machine? Especially the one directly under the HDM?
 
#11 ·

Quote:
Originally Posted by draganm /forum/post/19135800


triplington can you please verify that all 3 belly fans are working in your machine? Especially the one directly under the HDM?

One more thing, there's a panel right above the CLM that covers the ACON board and CCM. Can you please take this off and maybe put a fan back there to blow onto the CLM?

I really think it's the CLM as well. Tested this HDM here now for 24 hours with no problems.
 
#12 ·
I had (have) a similar heat related problem with my Marquee 81110+ ultra. I had a long thread about that over a year ago - but basically got an intermittent loss of vertical sync during the hot summer months (with the projector mounted against an insulated ceiling next to very warm attic). I tried chaning the CLM (now have two spares - one damaged because I inserted a chip backwards after deoxiting on the DPB (?)daughter board); easter egged the daughter board amongst the CLMs. Bought and tried both a new HDM and a new VIM. Examined the belly fans and found them all working. Never found the real cause. The intermittnent sync came back again this summer for the third year running.


Last weekend I had enough and the 3-eyed monster came down from the ceiling. Initially I found that the loss of vertical sync could be changed to a stable signal by removing the white connection on VIM. But then hours later the situation was reversed where I had to reconnect the white input when there was no "horizontal sync" to get a stable display - which lasted 10 minutes or so until I lost vertical sync again. I realize fall and winter are coming, but I was quite frustrated trying to find and correct this intermittent problem. In the end I decided it was no longer worth pursuing and will put the HC3800 digital I have up in the theater.


You probably have more reason to pursue with a 9 inch LC versus my 8 inch AC version.
 
#13 ·

Quote:
Originally Posted by RalphArch /forum/post/19136154


Bought and tried both a new HDM and a new VIM. .

new as in brand new from VDC or new to you but old /used



Quote:
Originally Posted by RalphArch /forum/post/19136154


Last weekend I had enough and the 3-eyed monster came down from the ceiling. Initially I found that the loss of vertical sync could be changed to a stable signal by removing the white connection on VIM. But then hours later the situation was reversed where I had to reconnect the white input when there was no "horizontal sync" to get a stable display - which lasted 10 minutes or so until I lost vertical sync again. .

so you could completely disconnect the Vertical BNC cable and the picture would remain stable for a while?
 
#14 ·
I wonder if it has anything to do with Humidity and small "micro arcs" from the HDM cables.


Both posters who had the issues live in areas where there is an ocean with in 100 miles,

And I think a marquee owner in Spain that lived on the ocean also had a similar issue.


And Ralphs goes away in the winter months when humidity is lower typically. I Know Humid air can lead to more frequent electrostatic and other electrical arching.


maybe add a de humidifier in the room for testing, since you had no issues with the AC on since it is basically a de humidifier as well that also cools the air.


The reason it happens more when the PJ gets warm is that the humidity with in the proximity of the hat components would increase since warm air can hold more moisture than cooler air, right?


Just my Hypothesis.


Athanasios
 
#15 ·

Quote:
Originally Posted by draganm /forum/post/19136800


new as in brand new from VDC or new to you but old /used

New to me but used - same model/part numbers as those in my Aug 98 81110+


so you could completely disconnect the Vertical BNC cable and the picture would remain stable for a while?
yes - several times - in many cases it only needs the white wire ((second from left) - but then that didn't last that long maybe 15 to 20 minutes and it would lose sync (horizontal reported with the black wire off) During the remainder of the year (s) - 9months it would be stable with all cables connected the whole time

Regarding the humidity comment - it's been way too hot here to live without the ac on full time. I am pretty sure there is very little humidity in our house and it has been kept pretty cool (76-77). The attic is sweltering hot and the pj is (was) hard up on the ceiling - hard to pass the power cord to the front through the gap.

One tid-bit I left out was the effect of running without the back heat sink enclosed. That gets quite hot and takes a fairly long time to heat up (which may be coincident with my loss of sync. When I tried this last summer it seemed to put off the onset of loss of sync - but I did not try it again this summer.

I recollect a discussion by someone about adding custom fans to the heat sync for supplemental cooling. I never did that.
 
#16 ·
I've been pouring over this thread and the other one Ralph posted. This problem really bugs me because I have an image in my mind of the marquee as a machine that simply never gets "incurable problems" and this marquee along with thee other 2 has really posed a major problem.

What I've found after all this reading is that the one thing all 3 machines have in common is you guys are using the VIM's RGB connectors vs. an internal HDMI card. I have done all my testing here with a Moome internal. WHY that would cause this problem I don't know but last night I ran my clients HDM and CLM for 12 hours solid and nothing. I even hit them both with a hair-dryer until the metal around them was uncomfortable to touch and nothing.


That's approx. 36 hours of testing the HDM and no fricking way it's bad. The only other board it could be at this point is the VDM but I ran that here was well previously overnight at 1080P. I have a feeling that simply testing the VDM here for hours and hours more would produce more of nothing.

This is what I'm going to do, re-cap Brent's CLM and send him the moome card out my test-mule. I'm going to figure this out if it's the last fricking CRT thing I ever do.

ARggghh, a Sony problem in a MArquee, say it ain't so
 
#17 ·
Drags dont you have a way to run RGBHV to your test mule? Id check that first. I have not read through these threads but the owners change out the RGBHV cables? i had a bad break out cable here that something similar. tell them to swap the blue calor for the H sync or V sync and see if the color goes out or not. Also check the Solder connections for the BNC's on the Vims. But if they swapped out Vims and the issue remained then id say cabling should be swapped out next.


If it is not that then id say bad connectors/ solderjoints on the Mother board or back plane.


Thats all thats left.


Athanasios
 
#18 ·
I guess I can still try to help figure this out even though the Marquee is now off the ceiling. It's not going back up in that room - I installed it by brute force with threaded rods and turnbuckles to adjust the four corners hanging on 4 chains each in the very hot insulated attic - not going back there. I will set it up in my basement and try it out. If all my speculation is correct it should be stable down there.


Either way I will post back after I try it out a while in a new location.


(I also noted the wrong cable above which I disconnected to get stable for a while when this happened in past - it was the black cable - last one on left looking at pj on ceiling)


One thing I also did somewhere along the line while troubleshooting was remove a resistor (or wire?) that disabled sync on green as discussed in some tech bulletin. It appeared to make no difference but I thought I would mention that as well. Other than that the boards are as received.
 
#19 ·
I'm using an internal Moome card, one of the older DVI types. I'll try setting up one of other inputs to see if that helps.


I checked the belly fans and they're all working OK. I removed the cover for the ACON board and pulled the board to get better air flow to the CLM board. The problem still occured after the "normal" 30 to 40 minutes. I even tried blowing on the board with a hairdryer on cold, but it didn't seem to have any effect.
 
#20 ·
Hello


I can test any boards here that you would care to send over. PM me if interested



Tim at E-Tech Phoenix
 
#21 ·
wow, so hair dryers, RGB cables vs. DVI-HDMI, swapping multiple modules, none of this makes a difference


I'm sending my cleint his CLM and HDM which I have tested here now for 3 days. Will move on to the VIM and VDM next if problem persists.

I hope it's not what Nash suggested, Mobo or back-plane, but that's really all that's left short of power supply's.
 
#22 ·
do the fans on the lvps work?


i would tear the entire pj apart remove the mobo and clean all contacts with alcohol.


remove the vdm cva and astig from the heatsink clean the heatsink and the fets on the 3 boards with ethanol and apply new cooling paste on the fets of the 3 boards.


i would solder all the fets on the cva too just to be sure (90 solder joints or so) this is done in less then 10 minutes.


if you have a known good working lvps and hvps i would test that first.
 
#23 ·

Quote:
Originally Posted by dvh99 /forum/post/19145280


remove the vdm cva and astig from the heatsink clean the heatsink and the fets on the 3 boards with ethanol and apply new cooling paste on the fets of the 3 boards

been done.

Quote:
Originally Posted by dvh99 /forum/post/19145280


i would solder all the fets on the cva too just to be sure (90 solder joints or so) this is done in less then 10 minutes.

the problem occured with CVA and STIG amps disconnected


I have one strong theory left. The one thing that would explain what could have happened from the time the boards were sent, tested, re-built, re-tested, and re-installed. The ONE thing I'm still considering is the RGB connectors on the VIM, the ones on top of the board. There's been instances in the past of these connectors on the board developing small crack's in the solder from being handled. I know they were only un-plugged and re-attached a total 6 times from my place to the clients but if the solder connection was a little shaky from the factory then this would do it and be heat related as well since the joint would swell as it warmed up. I've seen less than ideal wave-soldering on some marquee boards before. Mostly too little solder (cupped joints) or even air bubbles in the joint itself.
 
#24 ·
replacing the VIM had no effect. however determined fiddling by the owner of the machine finally paid off. This is what he found

Quote:
recall 2 has the RETRACE setting set to "Short", whereas the recall 01 has the RETRACE setting set to "Long". True enough, if I'm on recall 02 and the problem happens, if I go into the Pic menu and change the RETRACE to "Long", the problem goes away - changing the RETRACE back to "Short" causes the problem to occur. This is AFTER I heat up the HDM opening (so it's still heat related). Any clues from this?

any ideas? why would short re-trace cause the raster to become unstable after the PJ warms up and not when it's cold and why would switching to Long retrace cause the problem to go away? Is this simply the common problem with MArquee's not liking short porch settings and developing scan problems when they're not long enough?
 
#25 ·
With short retrace you giving the beam less time to settle down in the blanking section for the video signal. Now I do not know why heat would affect this unless it is causing a large change in resistance of the coils or maybe the amps driving them. So this problem only happens with the said HDM or with other HDM's?


I still think its the HDM connector on the mother board. have him move the Cage that hold the HDM, wiggle it a bit while it is doing the problem.


Now thinking more as I type, why would it only do it with Short retrace if it is a bad mother board connector , unless the signals are on different connector pins.


Athanasios
 
#26 ·
Athanasios,


haven't tried another HDM yet


I wiggled the HDM cage with the problem happening and there was no change (problem didn't get worse or better)


Also, once the problem starts to occur, if I blow hot air into the openings of the HDM cage on the side of the cage, the problem doesn't get worse quickly, whereas if I blow hot air into the cage hole below the HDM heat sink, the problem quickly gets worse (I can alternately make the problem come/go by blowing hot air and cool air into the cage hole).


thoughts?


Brent
 
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