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.: The X0 Project Discussion Thread :. (* unfinished project *) — Page 34

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Originally posted by: ripa
I was wondering if there are major physical differences between NTSC and PAL discs. Since the signal is encoded onto the disc, the player needn't do any actual signal coding/decoding, just read it off the disc and output it. .


This is really thee biggest misconception about laserdisc, that the video signal is somehow sitting on the disc in an easy to access (composite) format and is just opened and output with not much else going on. As mentioned in the previous post, what is actually on the laserdisc is very different. It is a heavily encoded FM signal that has no immediate correlation to composite video at all.
That is why a laserdisc player is so chock full of circuitry, and a big part of why they are so expensive and why they vary so much in playback quality. If it was as easy as just read signal and send it to the composite output, then the image quality from all players would be much the same - the huge differences in quality of output between laserdisc players is testament to the difficulty of decoding the signal cleanly and getting it to the outputs intact. They are a very different beast to any other sort of video player in existence.

A lot of NTSC players will in fact playback a PAL disc as if it was NTSC, but of course they process the signal as NTSC, so you just get a total mess in black and white, with no sync - nothing that is salvageable.

It is a cool idea, but one that won't fly - retrofitting a different laser assembly into an existing PAL player and improving its output circuitry is a more likely to succeed proposition.

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Originally posted by: Laserman You would be far better off taking an excellent PAL player like the 2950 or even the 925 and redesigning its circuitry to minimise noise than trying to turn the X0 into a PAL player.


I don't want to turn this thread into X0-PAL discussion, not at this moment anyway, but I'm curious if you did get hold of the 2950 service manual ?

IMO if the 2950 or the 925 circuitry by LSI design does not provide for a 'real' composite output, there could be other players to consider.
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There is an X0 on Ebay right now with many pictures if you like drooling over electronic gear.
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Originally posted by: Warp99
if the 2950 or the 925 circuitry by LSI design does not provide for a 'real' composite output.


(For those following along, "LSI" is "large scale integration," which means putting a lot of discrete electronic components functions together in one package. This is typically what happens in mature electronics, and is one large reason why the prices of electronic equipment (say, DVD players) start to plummet once that equipment hits the mainstream. It's also a reason why sometimes late-model equipment isn't quite as robust or tweakable as earlier-generation stuff -- you just can't get in there and swap out individual components to try and improve or change things.)



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Originally posted by: Laserman
I'm pretty sure I went onto more detail here on the boards in the past about how NTSC and PAL laserdisc players work, but if not I can post more info if anyone is interested.


Yeah tell us more! It's hard to find good info about the subject, and ever since I got my own DVL-909 a couple of months ago I gooten insatiable about the subject. For example, what do you know about the differences between the S9/X9/X0? Since a good '96 S9 is obtainable for about $1200, an X9 for twice that, and an X0 (if you can find one) probably for twice THAT. EDIT: OK $2800

That's no moon. It's a LaserDisc.

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Originally posted by: zion
You know guys, my birthday is coming up soon....


Happy birthday! Where should I send the card? 'Cause I ain't got no $2800...

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Originally posted by: Karyudo
Originally posted by: Warp99
if the 2950 or the 925 circuitry by LSI design does not provide for a 'real' composite output.


(For those following along, "LSI" is "large scale integration," which means putting a lot of discrete electronic components functions together in one package. This is typically what happens in mature electronics, and is one large reason why the prices of electronic equipment (say, DVD players) start to plummet once that equipment hits the mainstream. It's also a reason why sometimes late-model equipment isn't quite as robust or tweakable as earlier-generation stuff -- you just can't get in there and swap out individual components to try and improve or change things.)

Thanks Karyudo for filling in, yes you're right a LSI design would be difficult or impossible to alter. Only if Pioneer for some reason included a composite DAC (digital to analog converter) in the TBC (time base corrector) LSI circuit, i.e. if the same TBC circuit also was used for the players that only has composite output, it could be possible to connect a simple filter and video amplifier and get access to the composite signal before it enters the combfilter board.

Also other tweaks would be limited to the few discrete components surrounding the LSI circuits, some improvement could be made but requires some trial and error and it's timeconsuming and sometime you realize that the design was pretty optimal to begin with. The power supplies can usually be improved though, either with higher quality components or by altering the design but mistakes here can be very costly and you might end up turning the unit into a 10 kg paperweight.


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Originally posted by: Laserman
I thought I covered most of this before?


I'm sorry, but the search function seems to be a bit limited (only searches thread titles).

Anyway, I thought that the rotational speed difference would only yield a different frame rate but otherwise compliant PAL signal. I didn't think of the effects on the modulated signal. Since both PAL and NTSC video signals are FM modulated onto a 7,1MHz carrier, playing that back at a wrong speed would shift the carrier frequency, probably causing demodulating to fail. Also, I just noticed the technical discussion forum, where I should have posted this instead. I guess I got too excited about the prospect of playing back PAL discs on the X0. Sorry about that.
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Originally posted by: ripa
Originally posted by: Laserman
I thought I covered most of this before?


I'm sorry, but the search function seems to be a bit limited (only searches thread titles).

Anyway, I thought that the rotational speed difference would only yield a different frame rate but otherwise compliant PAL signal. I didn't think of the effects on the modulated signal. Since both PAL and NTSC video signals are FM modulated onto a 7,1MHz carrier, playing that back at a wrong speed would shift the carrier frequency, probably causing demodulating to fail. Also, I just noticed the technical discussion forum, where I should have posted this instead. I guess I got too excited about the prospect of playing back PAL discs on the X0. Sorry about that.

I don't think you should worry about it, finding or making a X0 equivalent PAL player has been a reoccuring topic since the beginning of the presevation efforts.

You can find detailed information of the NTSC and PAL laserdisc formats here:

The LaserDisc Technical Page

As you can see the NTSC carrier is 8.1Mhz and the PAL is 7.1Mhz, also the BW and sound carriers are different so very likely also the filters before the demodulation stage need to be changed.

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Originally posted by: Warp99
Originally posted by: ripa
Originally posted by: Laserman
I thought I covered most of this before?


I'm sorry, but the search function seems to be a bit limited (only searches thread titles).

Anyway, I thought that the rotational speed difference would only yield a different frame rate but otherwise compliant PAL signal. I didn't think of the effects on the modulated signal. Since both PAL and NTSC video signals are FM modulated onto a 7,1MHz carrier, playing that back at a wrong speed would shift the carrier frequency, probably causing demodulating to fail. Also, I just noticed the technical discussion forum, where I should have posted this instead. I guess I got too excited about the prospect of playing back PAL discs on the X0. Sorry about that.

I don't think you should worry about it, finding or making a X0 equivalent PAL player has been a reoccuring topic since the beginning of the presevation efforts.

You can find detailed information of the NTSC and PAL laserdisc formats here:

The LaserDisc Technical Page

As you can see the NTSC carrier is 8.1Mhz and the PAL is 7.1Mhz, also the BW and sound carriers are different so very likely also the filters before the demodulation stage need to be changed.


ZZZZZZZZ
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Then find another thread to read.

<span class=“Italics”>MeBeJedi: Sadly, I believe the prequels are beyond repair.
<span class=“Bold”>JediRandy: They’re certainly beyond any repair you’re capable of making.</span></span>

<span class=“Italics”>MeBeJedi: You aren’t one of us.
<span class=“Bold”>Go-Mer-Tonic: I can’t say I find that very disappointing.</span></span>

<span class=“Italics”>JediRandy: I won’t suck as much as a fan edit.</span>

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Uh oh, the cuckoo kids - that means it's time to go...

I will be leaving the X0 project mainly due to my failing health, also the direction it will take from this point on is beyond where I wanted to take the project anyway, so it is time for me to bid it farewell.

My departure won't affect it much I'm sure, as my portion of the X0 project is basically done, and the rest of the guys will take over and do their parts which I am sure they will do amazingly well - anyone that saw what Zion and mebejedi managed to extract out of what were awful captures can only imagine what they will do with a great capture as their base.

I will probably not be here much either, the treatment makes it very difficult for me to function on any useful level, but in my up time I will probably keep plugging away at my own thing but it will be completely away from the X0 project.

I won't really be able to answer any more questions about the X0 project in the future, as I won't really know what is happening! So I will be watching the site along with the rest of you to see how it progresses.

It has been a wild ride, I thank everyone for all the good times here, I really enjoyed the forums, learned a lot, and hopefully my contributions were useful also.

I'll be around here for a few more days, but probably not much longer, so to quote another great story - So long, and thanks for all the fish.
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Well... I'm sorry to see you go buddy. Out of all the posts I read I found yours to be the most informative. You constantly surprised me with tidbit of information which repeatedly rocked to the core my very own long held beliefs in the video field, and really... isn't that what it's all about? Thanks for making me think.

Cheers man and may the force be with you.

::Tosses a couple of snapper::

“I love Darth Editous and I’m not ashamed to admit it.” ~ADigitalMan

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well wish you the BEST Laserman,and a nice little package is on its way to you,i will be sending out tomorrow(wednesday)so take care and be well.
and a special thanks for ALL your contributions to the scene.
Dark Jedi
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This feels like the passing of an era.
I am fluent in over six million forms of procrastination.
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I think I can safely say that your presence on the board will be sorely missed. Best of luck to you, man.

I used to be very active on this forum. I’m not really anymore. Sometimes, people still want to get in touch with me about something, and that is great! If that describes you, please email me at [my username]ATgmailDOTcom.

Hi everybody. You’re all awesome. Keep up the good work.

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I'm gone for a while and return to bad news.

Laserman,

I hope that your treatment goes well and that you will make a full recovery soon. You will definitely be missed.

I'm still far behind on what I wanted to do. I still have to make a donation. I was hoping to be in my permanent position by now, but it is taking HR a long time. My fiancee and I have also moved and have had to put a lot of money into the house and have had to push our wedding date back a year. I hope I can get back to my project, but it probably won't be for a long time. I've also debated just selling off my LD Player and the LD's and forgetting it. It's a tough decision.

Anyway. I hope to see you return after your recovery. A nice break from the project will probably do you some good especially with so much else going on. Take good care of yourself.

Patrick
"When you have to shoot, shoot. Don't talk." - Tuco from The Good, The Bad And The Ugly
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I knew this day would come but I always hoped it wouldn't. Get well Laserman and you're always welcome back if you want. We'll hold down the fort in the mean time.



On a lighter note, I've uploaded the last newsletter article to the web site. The next issue will be out in the next couple days, so sign up now at the site if you haven't already or you'll miss it.

The first of the new articles we've been talking about will be up this week as well, so stay tuned.

My Projects:
[Holiday Special Hybrid DVD v2]
[X0 Project]
[Backstroke of the West DVD]
[ROTS Theatrical DVD]

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Every ending leads to a new beginning.

<span class=“Italics”>MeBeJedi: Sadly, I believe the prequels are beyond repair.
<span class=“Bold”>JediRandy: They’re certainly beyond any repair you’re capable of making.</span></span>

<span class=“Italics”>MeBeJedi: You aren’t one of us.
<span class=“Bold”>Go-Mer-Tonic: I can’t say I find that very disappointing.</span></span>

<span class=“Italics”>JediRandy: I won’t suck as much as a fan edit.</span>

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Originally posted by: Patrick R.
I'm gone for a while and return to bad news.
I'm still far behind on what I wanted to do. I still have to make a donation. I was hoping to be in my permanent position by now, but it is taking HR a long time. My fiancee and I have also moved and have had to put a lot of money into the house and have had to push our wedding date back a year. I hope I can get back to my project, but it probably won't be for a long time. I've also debated just selling off my LD Player and the LD's and forgetting it. It's a tough decision.
Patrick


I know what fun moving is, and how a house eats money. (perhaps you could do a 'Money Pit' restoration...)

Question is, how much would you actually get for the player and LDs these days? Enough to buy an IKEA coffee table?

Keep them hidden under the bed, you will probably get back to it one day - your stuff looked pretty promising last time I saw it.
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So does this mean the XO project is dead in the water?

sorry to hear about your failing health laserman you will be sorely missed, good luck in your treatments and god bless.

“Always loved Vader’s wordless self sacrifice. Another shitty, clueless, revision like Greedo and young Anakin’s ghost. What a fucking shame.” -Simon Pegg.

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Not at all, I'm finished with it, but as I said, my part was basically completed, and I didn't really intend to be involved in where it was heading from here onwards.

It will probably go faster now if anything, I haven't exactly been productive in the last month or so, if anything was probably beginning to hold things up a little.

I expect that the other guys will run with it now. Zion has already posted that the new newsletter is ready to rollout, and that a bunch of updates are imminent, so it is all still rolling along - keep your eye on x0project.com I guess - I'm sure they will keep you all posted as to progress.
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Very saddened to read about your health problems Laserman. I sincerely hope we see you back here in the future, you are a valuable and respected member of the forums.

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Take care, Laserman. I have a good idea of the sort of treatments you're talking about. Hope it goes well for you. I was thinking today how neat it would be if there was a OT convention someday. You would definitely have to be one of the guests of honor.
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