[jsaliga]

Hi Guys,


My Barco 1209s has been working fine until yesterday, when I moved it to a new custom built projector stand. After moving the projector (my brother in-law and I were very gentle) I began my setup procedure. While I was performing the optical focus in the installation menu I heard an arc, then the red gun went out followed immediately by the remaining two guns. I turned off the projector and pulled the SMPS and HV boards to inspect them. I could find no obvious signs of physical damage (i.e. a burnt component or evidence of bad solder joints). So I pulled all the boards and looked those over as well and reseated them. I turned on the projector again and when the HV came up there was an arc and no picture. Obviously I don't want to be doing that again. I also know that this problem could be something other than the HV board since there are protection circuits designed to shut down the HV in the event of a fault elsewhere such as the H-deflection board.


But I need a good place to start that would help me isolate this problem to a specific board. This is my fourth CRT projector but the first Barco that I have ever owned. So I can't say that I am really familiar with its design at this point. I do have a copy of the service manual and have been studying it closely but some suggestions from the Barco experts here would be very helpful.


Thanks in advance.


--Jerome

 

[audiman]

Check the big red leads, from the HV board, to see if they dont touch anything.

 

[jsaliga]

That was the first thing I checked. Thanks.


Anyone else? Curt? Cousin.It? Anyone?


--Jerome

 

[Cousin.It]

Well, it sounds like your pretty sure the noise is a high voltage arc right? When this happened did you open the projector up and check any of the status LEDs? I would expect the EHT board's red 'holddown' LED to be illuminated. After the arc I assume the projector, controller, fans and all were still functioning right?


When you moved the projector did you change from a table to ceiling mount?


I know you checked the SMPS, but I would check the solder joints on the transformers with a magnifying glass.


What else? I guess I would check that your output amps or neck boards are still fully seated on the crt sockets. I'd check that the hv leads going into the splitter are securely fastened. I'd also look around for accumulated dust.


How do you know that the red went out first and it wasn't all three at the same time? I would expect all three to act up simultaneously. But on that information and assuming this is happening basically every time you power up, I would probably disconnect the hv lead for the red tube at the splitter and run the green and blue tubes briefly and see what happens. If you haven't messed with the hv like this before I'm not sure I would recommend playing in this area though. I usually put electrical tape over the open splitter hole and tape the tip of the removed hv lead for added safety.


I'm actually wondering if your splitter went out, but the moving of the projector seems to be the obvious initiator to your new problem - that's what makes me wonder about the crt sockets being fully seated. I would be very careful. Whenever an hv issue appears I get semi-paranoid about spot buring the tubes and usually turn G2, contrast, and brightness way down until I think I'm past the issue.


What else can you tell us about this?


Mark

 

[jsaliga]

Mark,


Thanks for the reply. I tried to do as you suggested and disconnected the red tube but the projector will no longer power up. The standby light is on but main power is out.


I am going to need to get someone in here who knows more than I do to have a look at it.


--Jerome

 

[Chuchuf]

Jerome,

The two most common failures that I have seen on the 1208/808, which share most of the same circuitry as your 1209S are the SMPS bad solder joints and a failure of the quadripler, which will kill the HV. What I think happens to the quads is that they rdy out from lack of use, and then don't generally fail right away but rather after 5 - 20 hrs of use. It's one of the reasons we run the Barcos a min of 24 hrs prior to shipping, to make the quad fail if it is going to.

Could be the spliter as was mentioned, but we have never seen one fail like the quads do.

Also, if there is any dirt or dust buldup on any of the HV leads or in the HV area it can be very conductive.

But some other questions are in order, on the G2/diagnostic board, what lights are on or not on when the unit powers up? There are green and a red light. Or did you already answer this?


Terry

 

[jsaliga]

Terry,


The G2 + Diagnostics board had a green "straight board" as far as LEDs go. The Red SCAN FAIL light was not lit and CONV OVERVOLTAGE light was not lit.


The EHT Holddown LED on the EHT board was lit after the arcing occured. Unfortunately, the projector never lasted long enough for me to determine where the arcing was coming from. It certainly isn't coming from the card cage--that much I am sure of. It could be bad RGB socket seat, but I checked those out carefully after the first arc occured. The tubes are seated flush and squarely up against the socket.


The splitter block and HV cables are clean. I checked and cleaned those when I first brought the projector home.


I don't know if I have a blown fuse somewhere (I will check on that later in the week when I have time) that is keeping the projector from powering up now. In any event the arcing is what really worries me. I think if it is a fuse I will replace it and disconnect the tubes from the HV. I don't have any spot burns that I can see and I don't want to risk it.


Right now I am deeply disappointed. I was planning on taking a few days off this week (the first time off in nearly a year) to do some movie watching, but those plans obviously have gone into the tank.


Could a quadrupler or splitter block failure cause arcing?


--Jerome

 

[spatz]

I understand your HV is not coming up again but the projector is working ?

If so most likely the EHT has died, usually a few small transistors and a very hard to find opto are blown.

This is what I experienced a few times. The arcing could be inside the tube,

most likely because you moved the projector and some phosphor parts is short circuiting inside a tube.

You can try knocking on the outside of the tube to move this object but be careful I once cracked a tube doing this. But what choices do you have anyway.

 

[jsaliga]

Spatz,


When it first arced the projector was still running but I had no HV. But later I disconnected the red tube from the splitter and now the projector won't power up at all. It is stuck in standby. Hopefully it's just a blown fuse.


As you stated, there could be a short in a tube. But if so I really doubt that moving the projector caused it. When the problem occured the projector didn't last long enough for me to determine where the arcing was coming from.


I am going to have KevinD come over and take a look at it this weekend. Hopefully he can at least tell me what is wrong with the machine. If it is a tube then I am going to be without a projector for a very long time unless I get lucky and find another tube for a good price. God only knows what else was taken out. Repairing this projector could be a very expensive proposition, and I cannot afford to just take my lumps and go buy another projector. I may wind up parting it out.


So at the moment I am depressed beyond belief. This whole thing started when I made the mistake of selling a NEC XG110LC about a year ago. That projector was perfect. I haven't been completely happy with any projector (3 different machines) that I have owned since then. I'm getting to the point where I am throwing a lot of money into this hobby and not getting much out of it. Very disillusioned at the moment.


--Jerome

 

[spatz]

Sorry to hear that, but before you are parting it out I will take it

Actually I had my problems with NEC HVPS as well, so you will find

problems with HV on almost all projectors.

Honestly besides the many problems you can have with BARCOs the

HV generation in the newer model is quite reliable.


Now that the projector does not power at all this is really bad news, meaning first your HV died and later the LVPS.

The fuses usually only go when the BUPs are gone as well.

Hope I am wrong.

 

[jsaliga]

Spatz,


I understand there is risk of failure no matter which projector you buy. The way I see it I made one bad decision (selling the XG110LC that I owned for about a year) and two good decisions with bad results. One of the intervening machines I owned was bought from a dealer, and I was never happy with it. That really wasn't his fault per se, and he did work with me to some extent on my issues, but after months of owning it with no solution or satisfaction I had more than sufficient motive to want to get out from under it.


Now I have a projector that is dead. And it has in fact been a very long time since I have been able to sit down and watch a movie and enjoy the image. This problem may turn out to be a relatively simple matter but I really don't believe that will prove to be the case. The very fact that the red tube went out first followed by the other two leads me to believe that the red tube is the problem, along with a few other things that the arc took along with it. I think it is worthwhile to have Kevin take a look at it, but I have already prepared myself for really bad news.


I have no idea when I will have a functioning projector again, if ever. There are NO guarantees in this hobby.


--Jerome

 

[Cousin.It]

Jerome,


I wish I were close enough to come see what it is and isn't doing myself. HV arcing can propagate failures, but I did not expect you to not be able to get out of standby at this point. Is this even when you try to turn it on with the built-in keypad?


Originally I was thinking the splitter, quadrupler, and EHT but don't know if they're the source or possibly the victim if the red tube started it all. Did anything happen when you disconnected the red tube's HV lead or did it never power up again at that point?


When its in standby, is the controller acting normally? Standby power LED and flashing processor cycles LED? When you press the STBY button on the built-in keypad does the RCU LED flash briefly or sort of hang on?


Looking at the service manual it appears the main F100 fuse could blow and leave standby power alive. You have an ohmmeter? I'd check that one for starters.


In an earlier post you mentioned disconnecting the tubes from HV. I can't recall exactly, but I believe I read somewhere that at least one tube needed to stay connected to load down the HV chain. If I want to prevent any HV at all for a quick run I just pull the EHT board out.


Mark

 

[jsaliga]

Quote:

Originally posted by Cousin.It Jerome, I wish I were close enough to come see what it is and isn't doing myself. HV arcing can propagate failures, but I did not expect you to not be able to get out of standby at this point. Is this even when you try to turn it on with the built-in keypad?

I don't have the wireless remote. It will not power with the built-in remote.

Quote:

Originally I was thinking the splitter, quadrupler, and EHT but don't know if they're the source or possibly the victim if the red tube started it all. Did anything happen when you disconnected the red tube's HV lead or did it never power up again at that point?

After I removed the red HV lead it would not power up at that point.

Quote:

When its in standby, is the controller acting normally? Standby power LED and flashing processor cycles LED? When you press the STBY button on the built-in keypad does the RCU LED flash briefly or sort of hang on?

The controller does act normally. Standby power and processor cycles LEDs behave normally. I did not note the status of the RCU LED, but I can check that later tonight or tomorrow.

Quote:

Looking at the service manual it appears the main F100 fuse could blow and leave standby power alive. You have an ohmmeter? I'd check that one for starters.

I have a meter and will check the fuse. I have been meaning to do that but haven't had the time.

Quote:

In an earlier post you mentioned disconnecting the tubes from HV. I can't recall exactly, but I believe I read somewhere that at least one tube needed to stay connected to load down the HV chain. If I want to prevent any HV at all for a quick run I just pull the EHT board out.

I only disconnected the red. I can try pulling the EHT board and see if the projector will start.


Thanks Mark for your continued help.


--Jerome