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gjaky
Joined: 05 Jun 2010
Posts: 2802
Location: Budapest, Hungary
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| Posted: Tue Nov 19, 2013 6:38 pm Post subject: |
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| stridsvognen wrote: |
It would be realy cool if someone was able to make the 909 200Mhz capable or more... |
The single chip output (ie. non bridged) construction of the barco neck board won't let this happen, never existed such a circuit that could handle so high output swing AT that high speed. This is only reachable with bridged (differential) output.
_________________
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
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stridsvognen
Guest
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| Posted: Tue Nov 19, 2013 7:04 pm Post subject: |
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| gjaky wrote: | | stridsvognen wrote: |
It would be realy cool if someone was able to make the 909 200Mhz capable or more... |
The single chip output (ie. non bridged) construction of the barco neck board won't let this happen, never existed such a circuit that could handle so high output swing AT that high speed. This is only reachable with bridged (differential) output. |
Maybe someone can mod a Marquee board to work in a Barco.. 
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mp20748
Joined: 12 Sep 2006
Posts: 5689
Location: Maryland
TV/Projector: 9500LC Ultra / Super 02 and 03 VIM
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| Posted: Tue Nov 19, 2013 9:58 pm Post subject: |
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The real bandwidth bottle-neck in the 909 is in the neck boards, but I doubt it's also the single ended out IC by itself. And you won't know for sure until you can get the bandwidth to that chip.
The main problem is; I200 / OPA688. why they put that IC there blows my mind, when right after it, there is a Harris (now Intersil) HFA1100. And by using an HFA1100 (850Mhz) right after the OPA688 (look up the bandwidth) makes no sense, since the OPA688 was being used as a limiting chip. When Harris also made a HFA1130 limiter that is the exact same bandwidth as the HFA1100.
Now, Barco did exactly what Sony did in the G90 by putting a bunch of useless circuits in the video chain to boaster the features.
As limiter, the OPA688 allowed you to adjust the white ceiling as well as the black lower floor limit. Totally useless circuit if you're dealing with a legal video signal on the input (standard around the time it was manufactured).
Both chips should be replaced with something better, but it's not going to be easy to drop in replacements. And if you do find a set to work there, understand that you don't want to use limiting chips as replacements.
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mp20748
Joined: 12 Sep 2006
Posts: 5689
Location: Maryland
TV/Projector: 9500LC Ultra / Super 02 and 03 VIM
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| Posted: Tue Nov 19, 2013 10:22 pm Post subject: |
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| Diddern wrote: | | barclay66 wrote: | | gjaky wrote: | | This thread is so unexciting... yet can't get myself to not read, it's total waste of time :/ |
+1
Again one of the many analog vs. digital disputes. Going back to post #1, the only things I want to know are:
- Is Greg's statement true?
- Under which circumstances is it true?
- Can it be measured (technical objectivity)?
Regards,
barclay66 |
- NO and far from the truth. I can prove that. He's mods make it better but not comparable with a sony hw50, but for some CRT enthusiasts more than enough. And a really god CRT picture.
- better than original CRT nothing else.
- I don't know not my aria. |
I came back to give you an opportunity to prove me wrong, in that there's a lot more going on when you scale up the rate to very high resolutions and everything is going to be simply fine afterwards.
If you have Digital Video Essentials, load it into your blu ray player and from there bring up the same Smpte Pattern we use as a measuring tool.
Once you've done that, get out your camera (or cell phone camera) and take a close up picture of the center pattern group. after you've taking the picture, post it here.
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gjaky
Joined: 05 Jun 2010
Posts: 2802
Location: Budapest, Hungary
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| Posted: Tue Nov 19, 2013 10:50 pm Post subject: |
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| mp20748 wrote: | | (...) I doubt it's also the single ended out IC by itself. And you won't know for sure until you can get the bandwidth to that chip. |
There isn't any transistor datasheet out there that would allow to construct an amplifier like that, it's highly unlikely that they designed a transistor uniquely for barco that didn't hit the market later... Note the Marquee neckboards used the MRF transistors that had ft:1GHz in bridged configuration, later tse had to redesign the whole board to accomodate it to the much slower transistors (500MHz -I think?) he could get, and yet these transistors can't stand more than 100-110V. So on the 909 neckboard a roughly two times faster transistors would be needed with higher voltage limit. No Sanyo, MSK... chip can do this, not even close.
That amplifier can't be anything else just a single ended one, because only the Cathode is actively driven, G1, G2 are only biased.
_________________
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
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mp20748
Joined: 12 Sep 2006
Posts: 5689
Location: Maryland
TV/Projector: 9500LC Ultra / Super 02 and 03 VIM
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| Posted: Tue Nov 19, 2013 11:02 pm Post subject: |
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| gjaky wrote: | | mp20748 wrote: | | (...) I doubt it's also the single ended out IC by itself. And you won't know for sure until you can get the bandwidth to that chip. |
There isn't any transistor datasheet out there that would allow to construct an amplifier like that, it's highly unlikely that they designed a transistor uniquely for barco that didn't hit the market later... Note the Marquee neckboards used the MRF transistors that had ft:1GHz in bridged configuration, later tse had to redesign the whole board to accomodate it to the much slower transistors (500MHz -I think?) he could get, and yet these transistors can't stand more than 100-110V. So on the 909 neckboard a roughly two times faster transistors would be needed with higher voltage limit. No Sanyo, MSK... chip can do this, not even close.
That amplifier can't be anything else just a single ended one, because only the Cathode is actively driven, G1, G2 are only biased. |
When I went to VDC, I took a 909 neck board with me. Scott looked at it and said it was possible to get that bandwidth out of it, it's really based on the Vcc, and I would also like to point out to you that VDC (Scott) also had output transistors specially made for the Marquee neck boards, that looked very similar to the Motorola's. he later did an entire board design using Sanyo transistors as the outputs and drivers.
What you got to think about with single ended is the Vcc. In this case, it's 190VDC do you know of any other solid state video out amplifier operating at that high of a Vcc?
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gjaky
Joined: 05 Jun 2010
Posts: 2802
Location: Budapest, Hungary
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| Posted: Wed Nov 20, 2013 9:39 am Post subject: |
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| mp20748 wrote: | | gjaky wrote: | | mp20748 wrote: | | (...) I doubt it's also the single ended out IC by itself. And you won't know for sure until you can get the bandwidth to that chip. |
There isn't any transistor datasheet out there that would allow to construct an amplifier like that, it's highly unlikely that they designed a transistor uniquely for barco that didn't hit the market later... Note the Marquee neckboards used the MRF transistors that had ft:1GHz in bridged configuration, later tse had to redesign the whole board to accomodate it to the much slower transistors (500MHz -I think?) he could get, and yet these transistors can't stand more than 100-110V. So on the 909 neckboard a roughly two times faster transistors would be needed with higher voltage limit. No Sanyo, MSK... chip can do this, not even close.
That amplifier can't be anything else just a single ended one, because only the Cathode is actively driven, G1, G2 are only biased. |
When I went to VDC, I took a 909 neck board with me. Scott looked at it and said it was possible to get that bandwidth out of it, it's really based on the Vcc, and I would also like to point out to you that VDC (Scott) also had output transistors specially made for the Marquee neck boards, that looked very similar to the Motorola's. he later did an entire board design using Sanyo transistors as the outputs and drivers.
What you got to think about with single ended is the Vcc. In this case, it's 190VDC do you know of any other solid state video out amplifier operating at that high of a Vcc? |
The best transistor that could stand the 190V was the 2SC3600/2SA1406 that is about as fast (400MHz) as the 2SC3953/2SA1538 which were used in the latest Marquee neckboards (but in bridged mode). All in all I think no matter how good the IC on the barco 909 neckboard, it would be better if two of them would work in bridged mode.
_________________
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
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Diddern
Joined: 02 Jun 2013
Posts: 821
Location: Norway
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| Posted: Wed Nov 20, 2013 10:28 am Post subject: |
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| mp20748 wrote: | | Diddern wrote: | | barclay66 wrote: | | gjaky wrote: | | This thread is so unexciting... yet can't get myself to not read, it's total waste of time :/ |
+1
Again one of the many analog vs. digital disputes. Going back to post #1, the only things I want to know are:
- Is Greg's statement true?
- Under which circumstances is it true?
- Can it be measured (technical objectivity)?
Regards,
barclay66 |
- NO and far from the truth. I can prove that. He's mods make it better but not comparable with a sony hw50, but for some CRT enthusiasts more than enough. And a really god CRT picture.
- better than original CRT nothing else.
- I don't know not my aria. |
I came back to give you an opportunity to prove me wrong, in that there's a lot more going on when you scale up the rate to very high resolutions and everything is going to be simply fine afterwards.
If you have Digital Video Essentials, load it into your blu ray player and from there bring up the same Smpte Pattern we use as a measuring tool.
Once you've done that, get out your camera (or cell phone camera) and take a close up picture of the center pattern group. after you've taking the picture, post it here. |
I send it up later today. I hope to see something from you also.
When you take the picture I want to see all red, green and blue tube together just green is unacceptable.
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Andreas21
Joined: 02 Oct 2013
Posts: 582
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| Posted: Wed Nov 20, 2013 11:05 am Post subject: |
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| mp20748 wrote: | | Diddern wrote: | | barclay66 wrote: | | gjaky wrote: | | This thread is so unexciting... yet can't get myself to not read, it's total waste of time :/ |
+1
Again one of the many analog vs. digital disputes. Going back to post #1, the only things I want to know are:
- Is Greg's statement true?
- Under which circumstances is it true?
- Can it be measured (technical objectivity)?
Regards,
barclay66 |
- NO and far from the truth. I can prove that. He's mods make it better but not comparable with a sony hw50, but for some CRT enthusiasts more than enough. And a really god CRT picture.
- better than original CRT nothing else.
- I don't know not my aria. |
I came back to give you an opportunity to prove me wrong, in that there's a lot more going on when you scale up the rate to very high resolutions and everything is going to be simply fine afterwards.
If you have Digital Video Essentials, load it into your blu ray player and from there bring up the same Smpte Pattern we use as a measuring tool.
Once you've done that, get out your camera (or cell phone camera) and take a close up picture of the center pattern group. after you've taking the picture, post it here. |
I don´t know what you want to prove with this as I have already told you the VW1000 shows some artifacts in 1:1 pixel testpatterns(1080p), but I have never tested this pattern on the VW1000 and I will wait for diddern´s post berfore I make a comment.
_________________
http://www.minhembio.com/21Andreas
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stridsvognen
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| Posted: Wed Nov 20, 2013 11:13 am Post subject: |
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Easy now guys.. Im sure Mike just want to show some facts.. not to bash the sony, there is plenty of ways to see the CRT limitations with test patterns, so why be so scared to show how the digital behave.. Its not a pissing contest..
Would be nice if every body just relax, and dont defende each tech so much.. why not all try and find the weakness of what we have.
I find that more usefull, and easier to compensate for when we admit that nothing is perfect.
Your projector wont look different after you shown same screenshots, it will still be the same.
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Andreas21
Joined: 02 Oct 2013
Posts: 582
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| Posted: Wed Nov 20, 2013 11:38 am Post subject: |
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| stridsvognen wrote: | Easy now guys.. Im sure Mike just want to show some facts.. not to bash the sony, there is plenty of ways to see the CRT limitations with test patterns, so why be so scared to show how the digital behave.. Its not a pissing contest..
Would be nice if every body just relax, and dont defende each tech so much.. why not all try and find the weakness of what we have.
I find that more usefull, and easier to compensate for when we admit that nothing is perfect.
Your projector wont look different after you shown same screenshots, it will still be the same. |
I am calm, I have just seen the testpattern on my own VW1000 and it shows no artifacts. 
_________________
http://www.minhembio.com/21Andreas
Last edited by Andreas21 on Wed Nov 20, 2013 11:45 am; edited 2 times in total
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stridsvognen
Guest
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| Posted: Wed Nov 20, 2013 11:39 am Post subject: |
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| Andreas21 wrote: | | stridsvognen wrote: | Easy now guys.. Im sure Mike just want to show some facts.. not to bash the sony, there is plenty of ways to see the CRT limitations with test patterns, so why be so scared to show how the digital behave.. Its not a pissing contest..
Would be nice if every body just relax, and dont defende each tech so much.. why not all try and find the weakness of what we have.
I find that more usefull, and easier to compensate for when we admit that nothing is perfect.
Your projector wont look different after you shown same screenshots, it will still be the same. |
I am calm, I have just seen the testpattern on my own VW1000 and it shows no artifacts. |
Make a screenshot please.. And im sure Mike can explain what he is looking for.
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Andreas21
Joined: 02 Oct 2013
Posts: 582
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Diddern
Joined: 02 Jun 2013
Posts: 821
Location: Norway
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| Posted: Wed Nov 20, 2013 11:49 am Post subject: |
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| mp20748 wrote: | | Diddern wrote: | | barclay66 wrote: | | gjaky wrote: | | This thread is so unexciting... yet can't get myself to not read, it's total waste of time :/ |
+1
Again one of the many analog vs. digital disputes. Going back to post #1, the only things I want to know are:
- Is Greg's statement true?
- Under which circumstances is it true?
- Can it be measured (technical objectivity)?
Regards,
barclay66 |
- NO and far from the truth. I can prove that. He's mods make it better but not comparable with a sony hw50, but for some CRT enthusiasts more than enough. And a really god CRT picture.
- better than original CRT nothing else.
- I don't know not my aria. |
I came back to give you an opportunity to prove me wrong, in that there's a lot more going on when you scale up the rate to very high resolutions and everything is going to be simply fine afterwards.
If you have Digital Video Essentials, load it into your blu ray player and from there bring up the same Smpte Pattern we use as a measuring tool.
Once you've done that, get out your camera (or cell phone camera) and take a close up picture of the center pattern group. after you've taking the picture, post it here. |
Here, now can Mike explain.... Waiting
NB both pictures taken with iphone 4
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Diddern
Joined: 02 Jun 2013
Posts: 821
Location: Norway
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| Posted: Wed Nov 20, 2013 11:59 am Post subject: |
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Also want to see some real good CRT high end with the same pattern and nec picture.
Waiting.
With red green blue together. Not just green.
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mp20748
Joined: 12 Sep 2006
Posts: 5689
Location: Maryland
TV/Projector: 9500LC Ultra / Super 02 and 03 VIM
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| Posted: Wed Nov 20, 2013 12:09 pm Post subject: |
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Great.. that's good stuff. But you didn't show all six of the center line group. And I'm also glad that you included the NEC pattern..
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Diddern
Joined: 02 Jun 2013
Posts: 821
Location: Norway
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| Posted: Wed Nov 20, 2013 12:12 pm Post subject: |
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| mp20748 wrote: | | Great.. that's good stuff. But you didn't show all six of the center line group. And I'm also glad that you included the NEC pattern.. |
In the center the top one is the most important 1:1
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mp20748
Joined: 12 Sep 2006
Posts: 5689
Location: Maryland
TV/Projector: 9500LC Ultra / Super 02 and 03 VIM
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| Posted: Wed Nov 20, 2013 12:14 pm Post subject: |
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| Diddern wrote: | | mp20748 wrote: | | Great.. that's good stuff. But you didn't show all six of the center line group. And I'm also glad that you included the NEC pattern.. |
In the center the top one is the most important 1:1 |
I know, but that's not what I had asked for.
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stridsvognen
Guest
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| Posted: Wed Nov 20, 2013 12:15 pm Post subject: |
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Here is the same pattern on my JVC X7
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Diddern
Joined: 02 Jun 2013
Posts: 821
Location: Norway
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| Posted: Wed Nov 20, 2013 12:19 pm Post subject: |
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| mp20748 wrote: | | Diddern wrote: | | mp20748 wrote: | | Great.. that's good stuff. But you didn't show all six of the center line group. And I'm also glad that you included the NEC pattern.. |
In the center the top one is the most important 1:1 |
I know, but that's not what I had asked for. |
It's just the same more down white and black but bigger lines for SD if I'm not correct.
Then take a picture and show me how you want it for God sake. What do you want to prove.?
Here you have from the vw1000 give me CRT I'm exited now.
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