[Alan Gouger]

I have a Marque 9500LC.

The red tube is original. The projector has less than 100 hours.


The green and blue are rebuilds from VDC.


Problem is the beam spot size is larger on the VDC tubes.

This throws off everything.


Anyone encounter this before.


Chris Stephens now has this unit and is trying to work through this for me but he has never seen this before!



Thanks for any help.

 

[Curt Palme]

Yes, I have had this too. I talked with Eric Lang at www.projectorspecs. and he's having about a 10% reject rate. I sold a Marquee 8001 to the UK, and after 20 hours, the green has a pinspot burn (not due to a video failure). The set ran fine here for the first 20 hours, and for the first 19 at his place.


VDC does good work, but is not perfect yet.


Back int eh summer, I had 35% failure rate. I'm waiting for about 10 rebuilds right now of VDC tubes, and when they come in, I'll post again.


Send the tubes back to VDC for another rebuild.


Curt

 

[Alan Gouger]

Thanks Curt!

 

[mark haflich]

Happy Thanksgiving to Alan, Curt, and all. From what my video technician tells me, VDC has had a problem arise with its rebuild of the tubes used in the e-home marquee series. Evidently, the designed placement for the magnetics for these tubes does not allow for any slight misalignment of the tubes' innards. The stuff in side (forgive me for not being able to state the names of the innards parts) must be very very precisely located given the placement of the magnetics on the outside. A small error could be dealt with on other tubes by the ability to adjust the magnets more than they can be adjusted on the e-home tubes. So the bottom line is that VDC (a very fine company and one that does very good work) needs to be able to consistently site the innards with a greater degree of accuracy than they have been able to do so. From what I understand, they are striving exactly to do that and are more than willing to redo any tube they rebuild which can not be focused correctly (too large a spot size if you will). My sources of info re this are indirect. We have not used any VDC rebuilt tubes in any of our rebuilds. We will do so when VDC is able to deliver what we need,and I fully expect they will be able to do so as they gain experience in rebuilding the e-home tubes. The savings over new tubes are huge, almost 80% less. The problem, of course, if you get a tube that performs at less than the focus specs, and if it bothers you, you will have incurred substantial expenses in replacing the tubes in the projector and in set up. That's why we are waiting until they can get it right. I fully want to support their efforts and have several sets of tubes awaiting rebuild.

 

[Curt Palme]

Mark, your info seems pretty bang on.


Curt

 

[CINERAMAX]

Alan I hope you get this issue nipped in time for your exciting event.


Mark what was the resolution of the RED FILTER?


Did you try it?

 

[mark haflich]

Peter. I have not sent any e-home tubes to VDC yet for rebuilding. So I have not yet installed my red filters. When I hear that all rebuild problems are solved, I intend to send them a set of three 9 inch tubes and a red c element. I will then pull my almost new red tube from my 9500LC and substitute it with the red rebuilt. Then that red will be sent off just to have the red c-element installed. Then I will reinstall it in my 9500LC. It is a big hassel to pull and repull tubes and reset all up. I do not want to go through this unnecessarily for a rebuilt tube that has focusing problems. So I am waiting. If I had a new tube, I would just send it in for the c element. Installing that element doesn't touch the innards of the tube. Happy Thanksgiving Peter.


Alan. Best of luck with your event. Knock em dead Kid

 

[Tim in Phoenix]

Guys!


I concur with Curt, quality is not quite where we would like it, my grumble is mainly spot size. If VDC could get Matsushita electron guns it would likely solve the problems.

 

[mark haflich]

Tim. Can you elaborate a bit. By "guns" what exactly are you referring too? Are essentially "not factory parts" being used in the rebuilds? If Mat has stopped making the tubes, have they also stopped making the "guns". Are the guns outsourced by Mat. Can that source be located. Etc Etc. I do not expect you to know the answers to all these questions but what you do know and what you are allowed to disclose would be helpful. Happy Turkey day, Big Guy.

 

[KBK]

If the above situation is true regarding the re-built tubes, then logic tells you it plays a part in the average set of tubes. So, this means that there is going to be noticeable variance within a given set of original Panasonic tubes as well.


There is no way that the tubes from Panasonic could be 'perfect' either. Closer speced, and less noticeable.. and probably, for most, not a problem. but, and a Big BUT... If you are maximizing all of the other parameters of the PJ you are going to possibly run into a situation where one CRT out of the three might seem a bit softer than the others. This is exactly what I have run into, at the high numbers I am running at. The green does not seem to want to get as tight as the red and blue. This is under any load level. IT may be the fact that I have NEVER tried to re-adjust any of the tube's coils, at all. They seemed correctly located, and fine. SO, maybe I should try that. The difference is MINOR, I assure you, but it is definitely there. It would probably not be noticeable in any way, with a normally 'aspirated' PJ chassis.

 

[mark haflich]

I am not sure you are correct here Ken. The original manufacturer may know construction techniques better than a rebuilding company. Better jigs, etc or even more precise innards. Who knows? I do not but I can hypothesize why there might be a difference here between new and rebuilt. If the manufacturer fiqured out how to do it right, than given time, money, and enough incentive a rebuilder could get it right. However, these are not givens here. There is only one rebuilder, no competition, and new technologies are surplanting CRTs. That is why the Japanese are stopping production of the tubes we will need. I am stockpiling a replacement set for my baby. VDC is a large company with substantial resources and the incentive to keep the art of CRTs alive. However, anytime there is only one there is a danger that there will be none.

 

[Tim in Phoenix]

Guys!


The electron gun is the rearmost component inside the picture tube; it contains a heater section (filament) that heats the cathode (electron emitter) so that electrons can boil off the surface, and some grids (valves) that accelerate and regulate the stream of electrons that fire down the tube neck and strike the phosphor, the light from which gives us an image. The primary reason that VDC has taken months to get the rebuilds going is that they do not have access to MEC electron guns; they have been working with suppliers in the States, and not all of the experiments have gone so well. Early trials were plagued with arcing in the guns due to 34.9kv anode voltage found in the newer Marquees; they solved that but now focus is still an issue, and sometimes cut-off voltage, the innards of the guns must be precise in thousandths of an inch. R.P. Higgins of VDC will be a Guest on the Forum in a week or so, so be sure to send in your questions over there.

 

[mark haflich]

Thank you Tim. You are the best.

 

[Chris_Stephens]

I should point out, and im not sure Tim has mentioned this, but I feel Tim has been the person behind VDC even thinking about making Panasonic tubes for Marquee's. This may have led to VDC aquiring the Marquee !!!..


I think a very serious set of kudos go to Tim for this work he did with Charlie and VDC. He lent them a Marquee for study and has worked with them all along.


Certinally a big round of thanks needs to go to Tim !


Just thought I would point that out....


---------------------------


YES I have had headache the past week. I am a newbie to a rebuilt Marquee. Tim is the Guru on this subject for sure. I had swapped many a tube however I had never encountered any problems before.


The process of getting you Marquee tubed is VERY different from VDC then with Christie/Electrohome/Vidikron.


With Christie/Electrohome/Vidikron when you order tubes you get an assembly that has everything ready to go and aligned. You simply drop the whole thing in and bolt on the lens, pop on the neck board and plug in the HV lead. So minor alignment of the flare magnets on the neck is all thats required. You then send the old tube back.


With VDC its very different.

First you must first strip all the yoke and magnets off your current tube. Then send in your tube. You get one back and you must then place all the neck elements back on your self including aligning them correctly. This is more of a art then a science and is time consuming to be correct. The tube will have a wider variation on a few items then a Panasonic tube and require large adjustment. Like G2 (Cutoff) and focus in zones. Astig also varies alot more with a VDC replacement.


What I have seen is very interesting on these tubes. The red is Panasonic and blue and green are VDC.



What I see is that when contrast (Beam current) is really low (30) then there are no issues at all. Astig/focus/beam spot everything is good. However as you increase beam current (contrast) the spot gets sloppy. Its not really a bigger dot more like a halo. This is very linear as the contrast goes up the beam gets sloppier. The red stays together all the way to 100.



The other weird symptoms are that when the projector is set to 100 contrast and focus is varied from 0 to 100 the way the dot looks is very different at both ends of focus then the Panasonic tube. At a low contrast this strange effect is still visiable.



This is not a subtle problem. at 65 contrast the blue convergence line width is 4 times wider then the Panasonic. The green is like twice as wide. These tubes may be an exception.



So I am going to ship out these tubes today fed-x and have Charlie re-tube me. We will see.



After have long talks with Charlie Acurio I am certin with time these types of problems will be resolved. I have found VDC and Charlie VERY good to work with. Awesome support. In Charlies defense these tubes are VERY hard to make. If just anybody could make them they would have already !.


So, where do I find really deep technical theory on front projection tubes ?. This is hard info to come by.


I did find a very cool site that you guys may have already seen, it was new to me and really cool. here and here I admit after seeing these pages I have serious vintage CRT tube collecting envy.


I will post on here what I find with this whole process and the outcome of this saga.

 

[Tim in Phoenix]

Guys!


Chris is far too kind; VDC Florida likely would have acquired the Marquee operations anyway; R.P. Higgins worked for Christie not real long ago and certainly knows everyone involved. Incidentally, anyone buying tubes with full magnetics for fear of transferring over the old stuff to the new tube has been paying $400 too much, per tube!!! A technician Must understand tube magnetic alignments to extract full potential from each projector he retubes; tubes from the factory bought with magnetics are not necessarily aligned for the local terrestrial magnetics at the destination.

 

[Gertjan]

Quote:

Originally posted by tim tubes from the factory bought with magnetics are not necessarily aligned for the local terrestrial magnetics at the destination.

I'm holding off on having my 8501LC retubed, but i hope to do it sometime. I'm no expert by a long shot with this kind of stuff, as in, i've never took apart a CRT projector, and i really dont feel too comfortable doing it myself. So what are the options that are left to me? Do i need to send the entire projector to sombody like Tim? That would add another $500 or more to the whole operation easily, just for transportation of the darn beast


Gertjan

 

[mark haflich]

Tim is almost always correct. When buying new tubes, there is no need to pay for new magnetics. Likewise with a tube rebuiild. A trained videotech can easily change and adjust the magnetics. Some techs may not know how to do this. That is why companies like Vidikron only list tubes with the magnetics. Every tube I have ever ordered has been without the magnetics. Never ever a problem with changing them. Of course, I couldn't do it myself but techs like Tim, Chuck Williams, and Mike Parker can do it in their sleep.


Re the Georgia install. Find a competent set up tech in your area. They exist. Do not go for rebuilt tubes yet. Wait until VDC get the bugs worked out unless your tech is local and will not charge you for installing and uninstalling a "bad" rebuilt tube.

 

[Gertjan]

Thanks Mark. I'm anxciously awaiting to see when VDC can get the desired level of quality so that i can start thinking about getting my tubes rebuilt And now that you mention local techs: Tim gave me a competent contact for projectors here in Atlanta a while ago, so i'll probably deal with him when the time comes.


Gertjan

 

[Chris_Stephens]

Yes aligning the magnetics is quite easy, just time consuming. Its not aligning thats time consuming its disasembly and reassembly. Ok, even that only takes 10 minutes, but I have been in a hurry usally when replacing tubes it seems and it IS alot quicker to replace a fully assembled tube. This is of course the way Christie and Electrohome shipped replacements. The advantage to doing your own magnetics is that you can calibrate the focus coil while its off the tube


So developments from VDC.


I sent the tubes back priority overnite fed-x. Charlie tested them and found absolutly nothing wrong. He was/is vary happy to retube anyway however but its a time issue for Alan.


The problem I have with how these tubes are QC'ed is they are not QC'ed with magnetics. The problem I have is when I setup everything exactly, astig/flare/focus/optical and all that THATS when I see the problem. AND only on high beam current (contrast) at low contrast there is no problem. It appears the problem i see comes from how the focus and astig magnetics interact with the beam.


These tubes are not QC'ed with full magnetics correcting the beam to its smallest possible size at full contrast. VDC cannot currently verify what the beam spot size is on a tube because they can't focus, astig and deflect the beam.


I suggest the following.


1) VDC's CRT division aquire a Marquee and turn it into a QC station. This can not be that hard as VDC has aquired the Marquee from Christie. This projector would get sorta disembled somewhat and turned into a testing JIG. This JIG could be made to handle one tube at a time. The magnetics could be mounted to some fixed assembly so the entire assm could be slid on the tube neck and be sorta prealigned. The assembly then with tube mounted into its mechanics for the marquee could be dropped onto a preset fixed table with a pin attached to this table for instant alignment onto this fixed table. A lens could be mounted to the tube assm very quickly using just one screw to keep the lens on. The table is fixed to the floor and a screen is at a fixed distance from the table. A quick optical and flare adjustment with mabey minor center electrical and asitg and you are now seeing what the tube is really doing. Obviously the marquee chassis would be sorta under the table and wires would need to be extended.



This really isn't that hard to do, i have built many JIG's for testing and QC and this would be a few days project.


I believe the future manufacturing of this tube for production of all new Marquee's from VDC will justify this effort and expense. It would also instantly resolve support issues before VDC replaced a tube at VDC's cost by allowing a real life tube test that would show that the problem was with the projector not with the tube. This savings in cost would alone justify creating this test jig. As production begins on this tube for real production of the Marquee line it will be very important to quickly resolve if its the tube or projector because replacements costs could soar quickly.



I also believe after a short period of having this QC in place most issues would get resolved quickly and R&D would resolve issues and tighten variations. This would result in this JIG getting used just to sample a satistical number of tubes with a corresponding lowering of labor costs as quantity increased.


I suppose even a seperate company or division could do this work.


I think the future of the marquee projector in terms of awesome picture depends on these measures. I think its possible that VDC could improve the tube beyond what Panasonic did but it will require proper funding of equipment like test jigs and further R&D.



The other lesson here is that you get what you pay for. These tubes are WAY less expensive then the Panasonic tubes.


So......


I am now in search of a green and blue Panasonic tube for Alan. As you guys know Alan, mabey someone has a set of tubes below Christie/Electrohome costs that you might want to part with ? Email Alan if you do.


-----------------------------------------.



Tim, I understand from charlie you were indeed quite pivotal in thier having marquee's to develop the tube !. So I still think VDC would not be making tubes with your involvement. AND if you can't get tubes you can't make projectors SO im sure VDC would not have purchased the Marquee if they couldn't make tubes. SOOOOooo I still think you were very important to the whole Marquee production being aquired by VDC. If this had not happened then the marquee line was dead in 1.5-2 years.



So I still think Tim deserves credit for his involvement.

 

[Mark Glover]

Quote: from Chris Stephens,


"Yes aligning the magnetics is quite easy, just time consuming. Its not aligning thats time consuming its disasembly and reassembly. Ok, even that only takes 10 minutes, but I have been in a hurry usally when replacing tubes it seems and it IS alot quicker to replace a fully assembled tube. This is of course the way Christie and Electrohome shipped replacements. The advantage to doing your own magnetics is that you can calibrate the focus coil while its off the tube "


And Mark Haflich:


"A trained videotech can easily change and adjust the magnetics. Some techs may not know how to do this. "


Can you guys please elaborate on how to do change the magnetics. I started a new thread, -Magnetics change on Marquee