| Author |
Message |
redfox001
Joined: 16 Mar 2009
Posts: 2257
Location: The Netherlands
|
| Posted: Sun Feb 14, 2016 9:53 pm Post subject: |
|
|
I think pixels and pixelclocks are for digital guys. We are analogue people!
_________________
701s->runco933->8500ultra->cinemax->9500mp->919 splitpack + cinemax
|
|
| Back to top |
|
 |
redfox001
Joined: 16 Mar 2009
Posts: 2257
Location: The Netherlands
|
| Posted: Sun Feb 14, 2016 9:54 pm Post subject: |
|
|
If we allow pixelclocks next thing will be someone gets a digital projector 
_________________
701s->runco933->8500ultra->cinemax->9500mp->919 splitpack + cinemax
|
|
| Back to top |
|
|
GREG1292
Joined: 10 Oct 2006
Posts: 417
Location: indiana
|
| Posted: Sun Feb 14, 2016 10:11 pm Post subject: |
|
|
| mp20748 wrote: | | redfox001 wrote: | | I objected to Mikes clame that he can modify neckboards to very much higher bandwidth than they are standard and I provided pictures for that and arguments (there are only two high bandwidth parts modified). I am leaving it with this. |
Can I get anyone near by to come by my house so that I can for maybe the 10th time in the past year, show proof TECHNICALLY and on my screen that I can modify a Marquee neck board to not only do 300mhz (using an industry standard), but can also go beyond this.
I have posted these pictures many time in the past year, to include mentioned when other forum members were here and had also witnessed this. I've also posted shots showing the actual bandwidth (the generator puts it on the pattern) based on what was shown on the test pattern. Kurt (Strids) has also witnessed this and have also mentioned it here on this forum, to include some others.
And I would like to go one further to show what is actually done on the boards that are very capable of 100% resolving that resolution.
I would like for someone to come by so that I won't have to go through this every 30 days or so for the next year here.
The neck boards in my Marquee right now, can do well with the SMPTE pattern close to 270mhz, but I rate them at 250mhz. For higher bandwidth at or beyond 300mhz, I'll be making up another set for that purpose. I prefer the 250mhz boards because they have a lower noise floor and since I'm now were near needing 300mhz, it only make sense to not go that high. |
pixel clock does matter.
_________________
https://www.avforums.com/threads/worldwide-crt-projector-shootout.2000957/page-87
https://discuss.avscience.com/?topic=30.120
|
|
| Back to top |
|
|
cmjohnson
Joined: 03 Apr 2006
Posts: 5180
Location: Buried under G90s
|
| Posted: Sun Feb 14, 2016 10:12 pm Post subject: |
|
|
Just choose a standard for signals and measurements and quit arguing about it. The signal to noise ratio of this thread is getting dangerously close to the noise floor because of these pointless arguments.
I firmly believe that resolution on the screen is what we're after so just ignore even talking about pixel clock speeds and use a performance based standard. "I measure X MTF at point Y on test pattern Z at resolution A and scan rate B. " DONE.
Oh, in case you hadn't figured it out, I'm actually hoping to see 4K running on a CRT projector. And doing justice to it.
Optimistic, aren't I?
Well, I didn't buy that SINGLE available set of ultra resolution 9" CRTs from the Marquee 9500HR project just to run them at 800x600! Those tubes are intended specifically to be sharper than LUGs with a finer spot size and higher bandwidth tolerance. So, in theory, they're even better than the tubes in the Barco Cine 9. That's theory, not proven in practice.
I see that Mike's latest experimental mod pretty much bypasses the whole VIM amplifier sections anyway, and routes the signal through his own custom amplifiers. I may be interested in that setup.
Then there's the HDMI 2.0 issue. And, probably, an HDCP issue. I may know an engineer who would be able to design a circuit that would interface with the HDMI receiver and output analog RGB signals. If it can be done at not insane cost, I may commission him to do it, using the Moome HDMI interface card as a point of reference.
|
|
| Back to top |
|
|
gjaky
Joined: 05 Jun 2010
Posts: 2802
Location: Budapest, Hungary
|
| Posted: Mon Feb 15, 2016 6:18 am Post subject: |
|
|
Cmjohnson, your efforts are really welcome, but when you ask about MTF comparision you ask about a lot of information you don't want to know when it comes to modding... With the MTF you'll get the person's ability to setup a CRT projector, and the inherent effect of the tubes/lenses, or even of the room where it was used.
It is not a secret that I am almost finished to mate the Electrohome VNB to my NEC XG135LC, and added a AD834 multiplier stage (like VIM 03p) to the VNB directly, and omitted the original input amplifiers of the VNB. This thing happens to be usable even on Electrohomes, and not just on my XG.
But If I'd post about the MTF of this new board in my XG it would be pointless since all about my tubes and lenses are involved in the MTF that you don't want to know. Everyone involved such thing would have settle with the exact same machines too. And since you'll be the only with 9500 HR tubes no one else can help you with MTF readings. Not even by simply changing boards. But If I'd post something like that my neckboard has a 10%-90% rise time of 1.3ns at 55Vpp output on either G1 and K output (with the addition of my measuring equippment's limits) that is something more technical but also a better reproducible result.
My debate with Mike about his 'bandwidth' definition is over. I am an electro engineer by profession, at the university we had a lecture "signals and systems" which took 2 semesters about the concepts and techniques of linear and non linear systems and signals. I have different terms in my mind than what Mike uses but as I said earlier I'll leave this up to him.
_________________
projectors in the past : NEC 6-9PG xtra, Electrohome Marquee 6-7500, NEC XG 1351 LC ( with super modified Electrohome VNB neckboard !!!)
current: VDC Marquee 9500LC
The MOD: VNB-DB, VIM-DB
|
|
| Back to top |
|
|
mp20748
Joined: 12 Sep 2006
Posts: 5689
Location: Maryland
TV/Projector: 9500LC Ultra / Super 02 and 03 VIM
|
| Posted: Mon Feb 15, 2016 8:17 am Post subject: |
|
|
| cmjohnson wrote: |
I see that Mike's latest experimental mod pretty much bypasses the whole VIM amplifier sections anyway, and routes the signal through his own custom amplifiers. I may be interested in that setup |
The latest Mods does not use the first stage OpAmps and their pedestal (clamping) stages. We also bypass the Relays and everything else front end related. We then specially modify the Moome card and use it's analog buffer stage for the first stage of the video chain. By doing this we eliminate the need for a coupling cap on the first stage, because the Moome at this point becomes the ONLY source for the video chain. And that also allows the DAC on the Moome to be the ONLY source or reference for BLACK in the video chain, because the entire video chain also becomes Direct Coupled from DAC to neck boards. With this redesign, we also remove two more pedestal reference in the standard video chain. One pumped into the video chain from the CLM and the other coming from the first stage Opamps pedestal stage.
This entire redesign is an Direct Coupled Reference (DAC supplied from source) pedestal, that only uses the AD835 gain (Contrast control) on the VIM. The attached mini board on the VIM is very different from the previous version, because it does not use buffers or amplifiers. We also use the same supplied (from DAC) pedestal as reference for the internal menus.
The neck boards as well are very different, but maintain the original design concept. And because the original design was before the LUG tube, it unlike the G90 and Barco 909 was not designed to take advantage of the smaller spot size of the LUG tube. We made that happen along with some other really good clean and higher bandwidth changes. They also kick out more light. We were also thinking about replacing the AD835 for something else, but instead was able to tremendously improve on its terrible noise performance, to include get it to amplify tremendous bandwidth while still maintaining perfect linearity. The modified 03 VIM is no longer my preference.
| Quote: | | Then there's the HDMI 2.0 issue. And, probably, an HDCP issue. I may know an engineer who would be able to design a circuit that would interface with the HDMI receiver and output analog RGB signals. If it can be done at not insane cost, I may commission him to do it, using the Moome HDMI interface card as a point of reference. |
You should shoot this to Moome> I'm sure he'll be able to make this happen, because he's not under that restricted umbrella. Once he deals with the digital part of things, and of course it'll come this way to work out any analog issues.
|
|
| Back to top |
|
|
redfox001
Joined: 16 Mar 2009
Posts: 2257
Location: The Netherlands
|
| Posted: Mon Feb 15, 2016 9:22 am Post subject: |
|
|
Or in English. He passes the first autoclamp that can be disabled in the menu's too. But one high bandwidth part less. The old miniboard is only a switch nothing to improve there. The bigest improvement would come from using a ad834 like Gjaky does but he does not do that. The neckboards well I mentioned them. The blacklevel is clamped on the neckboards. The whole story about black from the moome is nonsence the black comes from the brightness controll and not from the video source. It is clamped at the neckboard in each and evry mod or board.
_________________
701s->runco933->8500ultra->cinemax->9500mp->919 splitpack + cinemax
|
|
| Back to top |
|
|
mp20748
Joined: 12 Sep 2006
Posts: 5689
Location: Maryland
TV/Projector: 9500LC Ultra / Super 02 and 03 VIM
|
| Posted: Mon Feb 15, 2016 9:32 am Post subject: |
|
|
| redfox001 wrote: | | Or in English. He passes the first autoclamp that can be disabled in the menu's too. But one high bandwidth part less. The old miniboard is only a switch nothing to improve there. The bigest improvement would come from using a ad834 like Gjaky does but he does not do that. The neckboards well I mentioned them. The blacklevel is clamped on the neckboards. The whole story about black from the moome is nonsence the black comes from the brightness controll and not from the video source. It is clamped at the neckboard in each and evry mod or board. |
LOL!!!!
|
|
| Back to top |
|
|
redfox001
Joined: 16 Mar 2009
Posts: 2257
Location: The Netherlands
|
| Posted: Mon Feb 15, 2016 9:37 am Post subject: |
|
|
rem
_________________
701s->runco933->8500ultra->cinemax->9500mp->919 splitpack + cinemax
Last edited by redfox001 on Mon Feb 15, 2016 4:14 pm; edited 1 time in total
|
|
| Back to top |
|
|
mp20748
Joined: 12 Sep 2006
Posts: 5689
Location: Maryland
TV/Projector: 9500LC Ultra / Super 02 and 03 VIM
|
| Posted: Mon Feb 15, 2016 9:43 am Post subject: |
|
|
| redfox001 wrote: | Tremendous inprove on the ad835 means adding a cap to the powersupply and ground. Magically now the bandwidth is even better than the datasheet says. It is unbelievable! Yes it is  |
Have you tried that yourself?
|
|
| Back to top |
|
|
redfox001
Joined: 16 Mar 2009
Posts: 2257
Location: The Netherlands
|
| Posted: Mon Feb 15, 2016 10:03 am Post subject: |
|
|
rem
_________________
701s->runco933->8500ultra->cinemax->9500mp->919 splitpack + cinemax
Last edited by redfox001 on Mon Feb 15, 2016 4:14 pm; edited 1 time in total
|
|
| Back to top |
|
|
mp20748
Joined: 12 Sep 2006
Posts: 5689
Location: Maryland
TV/Projector: 9500LC Ultra / Super 02 and 03 VIM
|
| Posted: Mon Feb 15, 2016 10:07 am Post subject: |
|
|
| redfox001 wrote: | | Yes I did! I was inspired by your vim and I did the job. I took two incredible caps and placed them on the unbelievable ad835 resulting in bandwidth improvement beyond what we I myself and me ever expected. You will not believe this! Don't. |
Well great, and now in hopes of your finally proven anything you've done, I posted a thread that will allow you to prove what great work you've done.. 
|
|
| Back to top |
|
|
redfox001
Joined: 16 Mar 2009
Posts: 2257
Location: The Netherlands
|
| Posted: Mon Feb 15, 2016 10:16 am Post subject: |
|
|
rem
_________________
701s->runco933->8500ultra->cinemax->9500mp->919 splitpack + cinemax
Last edited by redfox001 on Mon Feb 15, 2016 4:14 pm; edited 1 time in total
|
|
| Back to top |
|
|
mp20748
Joined: 12 Sep 2006
Posts: 5689
Location: Maryland
TV/Projector: 9500LC Ultra / Super 02 and 03 VIM
|
| Posted: Mon Feb 15, 2016 10:28 am Post subject: |
|
|
| redfox001 wrote: | | These tremendous improvements where so incredible no datasheet on the internet could support my clames. I even checked the Chinese datasheets and man that took some translation. The Japanese however they made some errors in it that did suppport my clames but I do not have them here you would not understand. |
Ok, in the 15 years of my working on that video chain out of my 21 years experience with the Marquee. And let me go further to say that I've had both engineers from both VDC and a former Electrohome engineer confirm that I have made great bandwidth improvements on the 02 VIM and did so with the AD835 being used.
Now this all happened before I was able to get the chip (AD835) to perform up to 300mhz flawlessly (this one you know nothing about).
And now you're telling me, all everyone including the manufacturer had to do was a put a CAP on one of the power pins...
LOL
|
|
| Back to top |
|
|
redfox001
Joined: 16 Mar 2009
Posts: 2257
Location: The Netherlands
|
| Posted: Mon Feb 15, 2016 10:33 am Post subject: |
|
|
rem
_________________
701s->runco933->8500ultra->cinemax->9500mp->919 splitpack + cinemax
Last edited by redfox001 on Mon Feb 15, 2016 4:14 pm; edited 1 time in total
|
|
| Back to top |
|
|
mp20748
Joined: 12 Sep 2006
Posts: 5689
Location: Maryland
TV/Projector: 9500LC Ultra / Super 02 and 03 VIM
|
| Posted: Mon Feb 15, 2016 10:51 am Post subject: |
|
|
| redfox001 wrote: | | Damn what gave it away? Was it the Chinese crap? |
You are notorious for posting stuff as fact, when you have neither personal experience with it yourself, nor have you verified that it's actually fact. That was one of Curt's points, to post PROOF to support your claims.
yet you keep challenging everything I do, when I'm the ONLY one that have proven the changes and have done so consistently for a many years.
Now, I intend to have you prove every rediculus claim that you post on these forums (BTW, something I really don't need to do).
Again, I started a thread for you to post to....but before you do and without any verification to putting that cap on the AD835 and making a huge improvement in bandwidth...or maybe I should have also used the word "Magical" which seems to be more appropriate. I can tell you without the fear of being wrong, because I know well that AD835..when you said you put a cap on the AD835 on one of my modified boards and it improved the bandwidth, my response to that is simply BS!
But I'll let someone else hopefully confirm that I'm right on that one.
And unlike you, I won't state would could happen because it would be wrong for me to do so, but I can say it won't happen on one of my boards.
|
|
| Back to top |
|
|
redfox001
Joined: 16 Mar 2009
Posts: 2257
Location: The Netherlands
|
| Posted: Mon Feb 15, 2016 11:11 am Post subject: |
|
|
rem
_________________
701s->runco933->8500ultra->cinemax->9500mp->919 splitpack + cinemax
Last edited by redfox001 on Mon Feb 15, 2016 4:14 pm; edited 2 times in total
|
|
| Back to top |
|
|
redfox001
Joined: 16 Mar 2009
Posts: 2257
Location: The Netherlands
|
| Posted: Mon Feb 15, 2016 11:24 am Post subject: |
|
|
rem
_________________
701s->runco933->8500ultra->cinemax->9500mp->919 splitpack + cinemax
Last edited by redfox001 on Mon Feb 15, 2016 4:15 pm; edited 1 time in total
|
|
| Back to top |
|
|
redfox001
Joined: 16 Mar 2009
Posts: 2257
Location: The Netherlands
|
| Posted: Mon Feb 15, 2016 11:28 am Post subject: |
|
|
rem
_________________
701s->runco933->8500ultra->cinemax->9500mp->919 splitpack + cinemax
Last edited by redfox001 on Mon Feb 15, 2016 4:15 pm; edited 1 time in total
|
|
| Back to top |
|
|
redfox001
Joined: 16 Mar 2009
Posts: 2257
Location: The Netherlands
|
| Posted: Mon Feb 15, 2016 11:56 am Post subject: |
|
|
| mp20748 wrote: |
Now this all happened before I was able to get the chip (AD835) to perform up to 300mhz flawlessly (this one you know nothing about).
|
From the datasheet:
The AD835 is the first monolithic 250 MHz, four-quadrant voltage output multiplier. This means -3db at 250 MHz. Did you mean Mega Pixel perhaps?
http://www.analog.com/media/en/technical-documentation/data-sheets/AD835.pdf
_________________
701s->runco933->8500ultra->cinemax->9500mp->919 splitpack + cinemax
|
|
| Back to top |
|
|
|
|
