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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: Sun Feb 14, 2016 10:12 am Post subject: |
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| redfox001 wrote: | | The modified neckboard of the marquee that is still a discussion worth. I compared modified neckboards to standard neckboards and surprise the standard neckboards where better and some where a lot better. So I am using standard neckboards in my video chain selected from 9. Strange it is that modifying took the bandwidth down but I have read someone else taking the opamp from the neckboards trying something soldering it back and never getting the performance back. I can not find that thread but some may know. Is it even possible to replace two allready over speced parts with higher bandwidth parts and getting a significant better bandwidth? Very strange, very strange. |
Was that the same test you used that showed on this forum that incredible bandwidth roll-off of the newer VDC neck boards?
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redfox001
Joined: 16 Mar 2009
Posts: 2257
Location: The Netherlands
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| Posted: Sun Feb 14, 2016 10:31 am Post subject: |
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This was one of the modified neckboard. Taken maart 2015 just after I got them. Little setup just bandwidth check. Two of these same bandwidth and one neckboard was broken. We discussed that.
This was a standard neckboard but also a standard moome. December 2015 a little better setup too 
Now the MP mods do something to improve the picture noisewise but bandwidth wise???
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redfox001
Joined: 16 Mar 2009
Posts: 2257
Location: The Netherlands
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| Posted: Sun Feb 14, 2016 10:44 am Post subject: |
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Don't misunderstand me. I like the modified moome more than the standard moome with blacks but its bandwidth is lower and that shows in some less sharpness. I do have to admit that proper calibrating blacklevel made the differences smaller but still I have it so why not use it. Also the other modifications not bandwidth related on the neckboards I prefer over non modified. Also the Vim02 shows a clear improvement in bandwidth over standard.
The thing I am disputing is that the neckboards are better in bandwidth as I have seen the boards from Wolfie and Strid and they show the same modifications. Two parts in the video chain. I can not believe they do miracles.
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701s->runco933->8500ultra->cinemax->9500mp->919 splitpack + cinemax
Last edited by redfox001 on Sun Feb 14, 2016 10:52 am; edited 3 times in total
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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: Sun Feb 14, 2016 10:51 am Post subject: |
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Lol.. it is truly interesting how much and often you spend time trying to prove that. Do you know how many times you have also posted on this same forum just the opposite of what you just posted.
So what is it, the Mods have made bandwidth improvements, or do you want people to believe they don't. What about your post on wanting to reverse manufacture them...now if the stock boards are better, whu would you want to reverse engineer them?
BTW, what neck boards do you have in your Marquee right now, and before you reply, don't forget not too far back you indicated what boards you have been using. So then, and this was pointed out to me. Why do you continue to slander me and what I do and still use my work in your projector?
Seriously, could you remove my boards from your projector if you are also going to continue to slander me??
Anyway and for the record, and I have pointed this out to you many times. Performance has never been a complaint with my mods. And while you're at it. Also remove the Moome card, because it's bandwidth performance is an MPmod..
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redfox001
Joined: 16 Mar 2009
Posts: 2257
Location: The Netherlands
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| Posted: Sun Feb 14, 2016 10:55 am Post subject: |
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Read again. I am disputing your clames on ridiculous bandwidth. I have always said the same and will continue to tell what I perceive as truthfull. And yes I use parts of the mods as I paid a lot of money so they are mine.
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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: Sun Feb 14, 2016 10:55 am Post subject: |
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| redfox001 wrote: | | The thing I am disputing is that the neckboards are better in bandwidth as I have seen the boards from Wolfie and Strid and they show the same modifications. Two parts in the video chain. I can not believe they do miracles. |
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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: Sun Feb 14, 2016 11:05 am Post subject: |
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| redfox001 wrote: | | Read again. I am disputing your clames on ridiculous bandwidth. I have always said the same and will continue to tell what I perceive as truthfull. And yes I use parts of the mods as I paid a lot of money so they are mine. |
If you have something that's inferior to what gets you better results, then why use it?
Also, you did not receive nor purchase the neck boards that I said had the listed bandwidth I posted, so how can you post on something as being truthful when in fact you know absolutely nothing about it, with zero experience first hand. And even with what you got, it has been proven so many times by others that they do far exceed the stock in bandwidth.
I'm told you were recently kicked off another forum for also making similar false claims -- I can prove every claim I've made, and I'm well positioned to do so...
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redfox001
Joined: 16 Mar 2009
Posts: 2257
Location: The Netherlands
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| Posted: Sun Feb 14, 2016 1:25 pm Post subject: |
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Sorry but when I look at this picture that you posted in your sales add I see the same parts modified. Takes some zooming.
I do not use those neckboards. I use standard with some noise mods.
About the other forum I deleted my account but am back as radiohead314 when I heared that Stridvogden is banned over there from Mac. He is not able to post as he insulted me Curt and goes on and on. Ask MacGyver yourself 
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redfox001
Joined: 16 Mar 2009
Posts: 2257
Location: The Netherlands
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| Posted: Sun Feb 14, 2016 1:37 pm Post subject: |
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You know what disturbs me the most Mike Parker is that you do not have a single problem with twisting the truth telling straight lies or threatening or whatever you think will get you the results. You do not seem to have the moral vallues that hold so many of us from doing all that.
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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: Sun Feb 14, 2016 1:52 pm Post subject: |
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| redfox001 wrote: | Sorry but when I look at this picture that you posted in your sales add I see the same parts modified. Takes some zooming.
I do not use those neckboards. I use standard with some noise mods. |
That set of boards go back quite a ways, so how it you keep posting about anything recent or the past two years. Plus, how can you reference a posted set of anything as what is or was being used at the time or even after. It's been a long time since I've changed that PNP driver, and hopefully that will help you to understand what great lengths that you go through to slander someone. It must be tough being THE ONLY person that has had bandwidth issues with the mods. What Wolfman experienced initially when he first got them turned out to be his older version Moome card - NOT the MODS. But of course you posted a smpte of the newer VDC neck board bandwidth and it's roff-off problem, for which anyone with any reakl knowledge of testing those boards would know once again you'll either doing something wrong, or you are also trying to slander Scott's work. Doing so does not make you look like an expert.
And your mention that you don't use those neck boards anymore is the BIGGEST LIE you've told so far out of the many you consistently throw out. Just look back over your many "bash the mod post" and see where you've even said you have improved on, many fixes, reverse engineered them. So many I'm not even going to waste time copy and posting them. I only hope that one day, that my one lone bandwidth complainer will remove anything that's related to me from that "can't post screenshots of" CRT projector you own.
And what does Kurt have to do with this discussion, why are you so insistent to bash or slander anyone who disagrees with you. Kurt like so many others have only pointed out to you how inept you really are. Now that's the truth
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tschaeikaei
Joined: 08 Apr 2013
Posts: 490
Location: Germany/Saarland
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| Posted: Sun Feb 14, 2016 1:55 pm Post subject: |
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May I ask a question? If we are talking about bandwith, where in the projector does this frequency occur?
As i understand the principle of CRT, bandwith is pixel clock. The frequency of the signal driving G1 on the tubes.
Am I right about it? So if i understand it correctly, the discussion about bandwith vs. highest possible pixel clock is pointless
because it is two words for the same thing.
If we look closer onto the G1 (or cathode?) of a picture tube trying to resolve 4k, the raw pixel clock (=bandwith needed) is 497,7Mhz,
raw meaning 3840*2160*60Hz. 1/497MHz gets me 2ns per pixel.
Nothing new, right?
So if i look into the spec sheet, VDC claims
| Quote: | | Marquee 9500LC-120 MHz bandwidth (-3dB). Marquee 9500LC accommodates 3 nanosecond pixels and digital clock rates over 300 MHz. |
Since some of you, especially Mr. Parker do create mods to archieve 250MHz bandwith, there must be a reason for this.
Horizontal retrace (quoting the spec sheet again) is 1.8µs, vertically 300µs.
So let's add 2160*1.8µs*60+300µs*60 and you'll get 251.28ms (Miliseconds!) that the electron beam must spend
doing retrace and this leads to the following: if the beam is useless 1/4 of the time, we could simply add 20Hz vertically,
just to include the retrace time to our pixel clock bandwith math.
3840*2160*80= 663.5MHz. 1.507ns per pixel.
If you look closer onto the pixel clock signal, you' ll see that a sine wave signal is not what we're talking about.
The signal has to be square wave, meaning that if you take a vertical 1on-1off pattern, the brightness of the individual
"pixel" has to be the surface between the curve and zero-line. Mathematically speaking the integral under the graph
between pixel start and next pixel start, which would be 1.507ns.
If we pick two random pixels, first of them "on", meaning bright or 100IRE, second one "off", meaning black.
If the curve is not a perfect square, one will bee under 100 and the other above 0 IRE.
And the edge between the two will be somewhat fuzzy.
This leads us to the conclusion that if the pixel clock is about 665MHz and the "on"- time for 1 of those pixels is 1.507ns,
the switching time of the corresponding device switching the beam current has to be significantly higher, somewhat in the magnitude of 10x the pixel clock. This is then the point when i realize that this perfect world scenario isn't realistic.
There are devices that can operate in the GHz- range, but not at high voltages.
This whole thing was meant to be a question and still is.
http://www.curtpalme.com/docs/ElectrohomeMarquee8110_8500lc_8500_9500_Brochure.pdf
Regards, Julian
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Marquee 9500U edgeblend P43 | NEC 9PG
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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: Sun Feb 14, 2016 2:00 pm Post subject: |
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| tschaeikaei wrote: | May I ask a question? If we are talking about bandwith, where in the projector does this frequency occur?
As i understand the principle of CRT, bandwith is pixel clock. The frequency of the signal driving G1 on the tubes.
Am I right about it? So if i understand it correctly, the discussion about bandwith vs. highest possible pixel clock is pointless
because it is two words for the same thing.
If we look closer onto the G1 (or cathode?) of a picture tube trying to resolve 4k, the raw pixel clock (=bandwith needed) is 497,7Mhz,
raw meaning 3840*2160*60Hz. 1/497MHz gets me 2ns per pixel.
Nothing new, right?
So if i look into the spec sheet, VDC claims
| Quote: | | Marquee 9500LC-120 MHz bandwidth (-3dB). Marquee 9500LC accommodates 3 nanosecond pixels and digital clock rates over 300 MHz. |
Since some of you, especially Mr. Parker do create mods to archieve 250MHz bandwith, there must be a reason for this.
Horizontal retrace (quoting the spec sheet again) is 1.8µs, vertically 300µs.
So let's add 2160*1.8µs*60+300µs*60 and you'll get 251.28ms (Miliseconds!) that the electron beam must spend
doing retrace and this leads to the following: if the beam is useless 1/4 of the time, we could simply add 20Hz vertically,
just to include the retrace time to our pixel clock bandwith math.
3840*2160*80= 663.5MHz. 1.507ns per pixel.
If you look closer onto the pixel clock signal, you' ll see that a sine wave signal is not what we're talking about.
The signal has to be square wave, meaning that if you take a vertical 1on-1off pattern, the brightness of the individual
"pixel" has to be the surface between the curve and zero-line. Mathematically speaking the integral under the graph
between pixel start and next pixel start, which would be 1.507ns.
If we pick two random pixels, first of them "on", meaning bright or 100IRE, second one "off", meaning black.
If the curve is not a perfect square, one will bee under 100 and the other above 0 IRE.
And the edge between the two will be somewhat fuzzy.
This leads us to the conclusion that if the pixel clock is about 665MHz and the "on"- time for 1 of those pixels is 1.507ns,
the switching time of the corresponding device switching the beam current has to be significantly higher, somewhat in the magnitude of 10x the pixel clock. This is then the point when i realize that this perfect world scenario isn't realistic.
There are devices that can operate in the GHz- range, but not at high voltages.
This whole thing was meant to be a question and still is.
http://www.curtpalme.com/docs/ElectrohomeMarquee8110_8500lc_8500_9500_Brochure.pdf
Regards, Julian |
You and I are on the same page here but I did not get answer. I was hoping to get an understand on the "sine wave" being relevant to this discussion, to include the Pixel Clock not being relevant. And by all means that huge bandwidth gap.. Thank you!
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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: Sun Feb 14, 2016 2:20 pm Post subject: |
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I also wanted to post the means and methods I use to claim my bandwidth ratings.
As seen in the picture I'm using a Chroma 2337. I then also bring up the SMPTE RP-133 and it's other resolutions patterns, because I've found also what Julien had posted that a proper 1 pixel on/off test is the best for end of line confirmation. So do not that I am using 1920
upload images free
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cmjohnson
Joined: 03 Apr 2006
Posts: 5180
Location: Buried under G90s
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| Posted: Sun Feb 14, 2016 2:45 pm Post subject: |
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| gjaky wrote: | One should explain to me why to mix the bandwidth and pixel clock terms, they are not the same!
Do you have a CD player? The sampling rate there is 44.1kHz, yet the maximal output freqency is 22.05kHz -everybody knows, no one complains about it.
Same with the video: at 297MHz pixel clock (sampling rate) your maximal signal output is a 148,5 MHz sine, so if you can resolve that please don't claim it as 300MHz bandwidth. |
Don't forget that the video chain is an ANALOG video chain, from the moment it leaves the Moome HDMI input card or whatever source there is that creates the analog signal going into the VIM.
As such, talk about pixel clocking in the ANALOG VIDEO CHAIN is completely irrelevant.
That's something for the HDMI card to handle, when it comes to analog video chain bandwidth we DO NOT CARE about the pixel clock rate.
It's important for generating the test signal over HDMI, but are we talking about developing an HDMI receiver with analog outputs, or improviing the bandwidth of an analog video chain?
Don't fail to see the forest because of all the trees in the way.
It stands to reason that if the HDMI 2.0 specification describes a maximum link bandwidth of 297 MHz, then it will not take any more bandwidth than that to display the complete signal.
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gjaky
Joined: 05 Jun 2010
Posts: 2802
Location: Budapest, Hungary
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| Posted: Sun Feb 14, 2016 2:54 pm Post subject: |
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| Quote: | | That's something for the HDMI card to handle, when it comes to analog video chain bandwidth we DO NOT CARE about the pixel clock rate. |
We do not, but Mike Parker does. If he can display a test pattern with 297MHz pixel clock he claims 297MHz analog bandwidth this is what bothers me how this comes?
Start from the begining, imagine a video signal that was recorded by an actual camera at 1080P 24Hz that is about 55MHz pixel clock, even frame tripled the pixel clock will be 165MHz, now because of the Nyquist theorem the signal really can't contain signals higher frequency than 165/2 (when frame tripled), and in fact they were really filtered at the time when it was shooted by the camera.
But then let's talk about square waves. square wave at frequency f0 has spectral components only at odd harmonics (f0*1, 3, 5, 7 etc.) Reproducing a square wave at f0=148MHz (pixel clock= 297MHz) have the first harmonic at 445MHz, second harmonic at 742MHz and so on... so I am still curious how did he come to the conclusion of his bandwidth is 300MHz, also really curious how one can tell by eye if the displayed pattern is in fact a sine or a square at 1 on 1 off.
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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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redfox001
Joined: 16 Mar 2009
Posts: 2257
Location: The Netherlands
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| Posted: Sun Feb 14, 2016 3:05 pm Post subject: |
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| mp20748 wrote: |
And your mention that you don't use those neck boards anymore is the BIGGEST LIE you've told so far out of the many you consistently throw out. |
These are the neckboard you modded. You might recognise the parts. Kind of difficult to use them now 
You might note that I do not use the new transistors or opamps on my standard boards in the marquee as they are still on these ones.
It turned out that these 2005 boards where useless after modification by Mike Parker. Only good for parts 
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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: Sun Feb 14, 2016 3:26 pm Post subject: |
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| gjaky wrote: | | Quote: | | That's something for the HDMI card to handle, when it comes to analog video chain bandwidth we DO NOT CARE about the pixel clock rate. |
We do not, but Mike Parker does. If he can display a test pattern with 297MHz pixel clock he claims 297MHz analog bandwidth this is what bothers me how this comes?
Start from the begining, imagine a video signal that was recorded by an actual camera at 1080P 24Hz that is about 55MHz pixel clock, even frame tripled the pixel clock will be 165MHz, now because of the Nyquist theorem the signal really can't contain signals higher frequency than 165/2 (when frame tripled), and in fact they were really filtered at the time when it was shooted by the camera.
But then let's talk about square waves. square wave at frequency f0 has spectral components only at odd harmonics (f0*1, 3, 5, 7 etc.) Reproducing a square wave at f0=148MHz (pixel clock= 297MHz) have the first harmonic at 445MHz, second harmonic at 742MHz and so on... so I am still curious how did he come to the conclusion of his bandwidth is 300MHz, also really curious how one can tell by eye if the displayed pattern is in fact a sine or a square at 1 on 1 off. |
Look at the resolution on the generator and then check it with a bandwidth calculator. But before you do, tell me what bandwidth is 1600X1200 /60hz using your formula
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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: Sun Feb 14, 2016 3:35 pm Post subject: |
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| redfox001 wrote: | | mp20748 wrote: |
And your mention that you don't use those neck boards anymore is the BIGGEST LIE you've told so far out of the many you consistently throw out. |
These are the neckboard you modded. You might recognise the parts. Kind of difficult to use them now
You might note that I do not use the new transistors or opamps on my standard boards in the marquee as they are still on these ones.
It turned out that these 2005 boards where useless after modification by Mike Parker. Only good for parts
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Are those the same boards that I asked you to not mess with and you went ahead and caused much damage. One again, I'm reminding you of the many emails on this and your apologies. Again, before you post this, don't forget the emails
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redfox001
Joined: 16 Mar 2009
Posts: 2257
Location: The Netherlands
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| Posted: Sun Feb 14, 2016 3:36 pm Post subject: |
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I think you can see that they are the same boards. Look at the electrolytic cap.
Note the potting material
And see how I removed it being a butcher? hmmmm.
Also note the original soldering skills from Mike Parker. Solder dots at caps etc.
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redfox001
Joined: 16 Mar 2009
Posts: 2257
Location: The Netherlands
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| Posted: Sun Feb 14, 2016 3:44 pm Post subject: |
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