CurtPalme.com Home Theater Forum

cmjohnson · Joined: 03 Apr 2006 Posts: 5180 Location: Buried under G90s

You may recall that a few years ago, VDC developed the enhanced, higher resolution Marquee 8500HR, which TSE was involved with the development of. He was getting 2048x2048 resolution out of the 8500 with a respectable MTF value at a normal viewing contrast level. The primary modification vs. the regular 8500 of the time was that the HR had higher resolution capable CRTs made by VDC subsidiary Lexel Imaging.

They also prototyped a 9" version, the 9500HR, with similarly high resolution 9" CRTs.

The Lexel CRTs have electron gun assemblies that generate a finer electron beam and spot size than either LCP or LUG tubes.

As I understand it, the HR project was a technical success but a sales failure. I believe that VDC actually sold ZERO 9500HRs and the only ones that exist were the prototype/demo units. The 8500HR didn't fare much better.

Well, I've made a deal and will soon be receiving the only existing 9500LC HR CRT tube assemblies in the world that are not in a VDC owned demo projector. They're already mounted in LC chambers but I'm not sure (yet) which magnetics, if any, they will be coming with.

Their potential resolution should be around 2700x2700 with the same MTF that TSE was getting out of the 8500HR. Maybe more, as the HR actually used the stock Thomson focus yokes. Further improvements by using better optimized focus yokes (Frankenyokes, of course!) may yield still finer spot size.

Of course, that's only useful if you have a source that can deliver that kind of resolution.

The project gives me a faint hope of being able to even THINK about the possibility of a 4K capable projector, with the understanding that the bandwidth of the video chain is inadequate for 4K. (Hey, Mike Parker, how far out can you boost the video bandwidth, anyway?)

What I expect out of these tubes, if i am able to successfully use them, is simply to get unprecedented sharpness out of them at 1080p. MTF values should be quite impressive.

There is a slight chance, via usage of an up to date HTPC, of running 4K content on it, scaled down to less than 4K but higher than 1080p. Maybe...2.5k? Whatever, at the very least I can count on getting a really crisp, sharp HD picture.

This is probably going to force me to make another attempt to optimize my "final" set of Frankenyokes, which is a project I never actually got around to completing.

They'll be going into a Marquee chassis with an MP modded 02 VIM and MP modded neck cards, and a Moome HDMI input card. None of the mods are latest/greatest versions but I think they're more than adequate for this round of experiments.

This should be fun.

My greatest single performance concern will be with light output from the new tubes. With a finer beam spot size, it implies that their light output will be down, just like how with LUGs the light output is less than LCPs for the simple reason that less phosphor is being excited by the beam at any given moment. Maybe they have a higher output phosphor? Don't know.

haireez · Posted: Sat Feb 06, 2016 8:27 am Post subject:

Looking forward for the results. 😊

cmjohnson · Joined: 03 Apr 2006 Posts: 5180 Location: Buried under G90s

They're now in my warehouse.

Part number is 9LPLCP09(color code), made by Lexel Imaging.

They came with a full set of brand new magnetics. but no plastic housing assemblies and no neck cards.

Apparently I won't even be able to attach the neck card cage as they're clocked one pin off from standard. Unless I want to make a custom neck card cage, that is.

I got some bad news about the remaining Marquee lenses and parts inventory. Apparently much of it was purged from the inventory two years ago.

There just MIGHT be some brand new sets of Elcan HD10E lenses in the county dump. Sad

If I knew where to dig, I'd be digging for them now.

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mp20748 · Posted: Thu Feb 18, 2016 11:22 pm Post subject:

cmjohnson · Joined: 03 Apr 2006 Posts: 5180 Location: Buried under G90s

Isabel and Mary, at VDC, when I picked up the tubes today. They checked and confirmed that inventory numbers on the lenses are zero.

Come to FL, bring a shovel and a metal detector, and let's start dump digging.

There are some things left but I asked specifically about the lenses.

cmjohnson · Joined: 03 Apr 2006 Posts: 5180 Location: Buried under G90s

Here they are, pristine and with great potential that I hope to fully exploit.

**AnalogRocks** · Posted: Fri Feb 19, 2016 3:13 am Post subject:

I wondered what became of the ultra-res stuff. I wasn't sure they even made 9" ultra-res units.

Glad to see at least one set made it into proper hands

Too bad about the parts dumping . I wish they would offer it here.

cmjohnson · Joined: 03 Apr 2006 Posts: 5180 Location: Buried under G90s

I'm hunting down the demo units. They made at least one 8500HR and a 9500HR. I have already requested first dibs on them if they are available and still exist.

A great thing about these tubes is that they are true LCPs with upgraded electron guns, so they will be compatible with lower refresh rate than the fast decaying LUG tubes.

Since the goal is to push into, to mangle a phrase, "resolutions never before seen by white man on a CRT projector", having the longer persistence LCP spec phosphor is a huge bonus. Odds are there won't be enough bandwidth to spare to run the higher refresh rates that we usually like to see. I'm really expecting nothing faster than 60 Hz progressive at the very most, and that would be at around 3K resolution. If that. Bandwidth is at a premium for this project and it's going to require me to push the chassis into the stratosphere.

I expect to be spending some money and systematically modding an entire chassis, using the Chris Stephens playbook as well as more modern upgrades.

Those wet slug tantalums are not cheap. But I'm going to be buying a few.

I've already figured out a way to get HDMI 1.4 into the projector. Use a Moome card for Sony projectors, which is too short and pinned differently, with a one-off custom made adapter card. That will probably cost me 200 bucks just for the adapter itself.

Part of my information quest is to find out definitively what model number of focus yoke is used on the Barco Cine 9. Because
it would make sense that with the Cine 9 being the sharpest machine on the block with LUG tubes, it would probably be a very smart idea to start out with the same kind of focus yokes. I probably HAVE a set, I just don't know which set is which.

So if anybody has been able to get inside a cine 9 and read off the white label on the focus yokes, I'd sure like to know that information.

It should say something like KF2302 or KF3203 or something vaguely similar.

redfox001 · Joined: 16 Mar 2009 Posts: 2257 Location: The Netherlands

Kf3212

barclay66 · Posted: Fri Feb 19, 2016 10:56 am Post subject:

cmjohnson · Joined: 03 Apr 2006 Posts: 5180 Location: Buried under G90s

Updates and corrections: VDC still fully supports the Marquee line and can build complete new Marquees if asked, other than provide lenses. All other parts are available.

As for these tubes, look at the part numbers. LCP is right in them. Phosphor is "regular", not the fast P43 type. The difference is in the electron gun, which shoots a finer beam than LUGs. Or CAN, if you set everything up right.

Due to an appalling lack of documentation, I do not yet know if they have the extra control grid that LUGs do. If they do, then I willl be looking to make best use of it.

I'm going to shoot an email to Lexel and see if they have some docs.

A funny thing about these is that they were made with the electron gun assemblies clocked wrong. They're rotated a little to the left. The neck cards will fit on OK but the whole card will be rotated so I probably won't be able to put card cages in the housings.

mp20748 · Posted: Fri Feb 19, 2016 2:23 pm Post subject:

barclay66 · Posted: Fri Feb 19, 2016 2:37 pm Post subject:

mp20748 · Posted: Fri Feb 19, 2016 3:21 pm Post subject:

mp20748 · Posted: Fri Feb 19, 2016 4:11 pm Post subject:

Hey Barclay,
that literature says an "1 MEG" resistor should go on that pin 7 to ground. The Marquee (both newer VDC and older Electohome) neck boards use "330K"

The G90 uses a "10 MEG"

The Barco Barco 909 uses "1MEG"

Question: since this is related to capacitance, do you think the difference in value would affect the sharpness because I'm changing to the 10 MEG that the G90 uses?

gjaky · Joined: 05 Jun 2010 Posts: 2802 Location: Budapest, Hungary

cmjohnson · Joined: 03 Apr 2006 Posts: 5180 Location: Buried under G90s

It would be nice to find out quickly if the change in that resistor makes an apparent difference.

It shouldn't affect anything not equipped with LUG tubes or tubes with the extra grid.

redfox001 · Joined: 16 Mar 2009 Posts: 2257 Location: The Netherlands

Normally with tubes those resistors are just to blead charge from those grids.

redfox001 · Joined: 16 Mar 2009 Posts: 2257 Location: The Netherlands

With tubes you can controll the grid letting the cathode to ground or use a grounded grid (biased grid) and controll the cathode. This last one has less miller coupling between cathode and grid and allows higher bandwidth. Using a pentode instead of a triode with tubes introduces extra grids to make the miller coupling even lower and increasing bandwidth.

My guess thse tubes have more grids than lugs?

redfox001 · Joined: 16 Mar 2009 Posts: 2257 Location: The Netherlands

Perhaps they us micro channel plate technology?
http://w140.com/tekwiki/wiki/Micro-channel_plate_CRT