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Discussion Starter · #1 ·
I have an LT-150 front projector. For those not familiar, it is an XGA fixed-pixel display. In addition to VGA, the LT-150 will accept an HDTV signal over its component input. One complication is that the component input is in the form of the same HD-15 connector that is used for VGA. My first idea for a solution was to run the two sources into a KVM switch and use that to change as needed. (I started out looking at DirecTV, but ran into LOS issues.) I am now focusing on a PCI card solution, since I use an HTPC.


I am a little confused about how these cards work. I will attempt now to regurgitate what I read in the FAQ: please help me out if I get something wrong.


Most of the cards are hardware based and send the HDTV signal to the monitor via component signal. You can either send your VGA out to a separate monitor, or in some (all?) cases pass it through the HDTV card to the HDTV monitor. In this case, it appears that I would still need to use the KVM to switch between the VGA and component signals. Am I making sense?


The Fusion HDTV-II card performs decoding in software. It sends the video signal through the PCI bus and uses the video card to output the signal to the monitor, much like a regular TV-tuner. (In fact, it also has one of those on the same card). I also have a Radeon 9800, and I understand this gives me the capability to send a component signal out via an optional DVI to Component dongle.


I am leaning towards the Fusion card. It is the least expensive, and my system is certainly stout enough to handle the software decoding work. Also I may be able to avoid the KVM which is added cost and possibly impact to a clean video signal. Also, it does allow me to feed the projector its native resolution.


Some questions, general and specific:


I noticed on the DVICO site that the reqs. are for Intel CPUs. I am assuming they mean "Pentium 3 class", and not Intel specifically, as I have an AMD 3200+. Is this correct?


How do you calibrate for HDTV material? Is this done with the hardware overlay? The HDTV software? Is there a good source to calibrate with (similar to Avia), or am I going to have to be eyeballing it?


Against conventional wisdom, would it be better to send the projector a component signal than to send it XGA? I could do this with the aforementioned dongle and accomodate the dual signal paths with a KVM. But do I want to bother?


Does the AC-3 decoding in software work well with the SPDIF out on an NF2 motherboard?


How sensitive is the demodulator? According to what I am able to glean, I live in an area where a small non-directional antenna should be sufficient when using a conventional receiver or STB. Will this still be sufficient? Can I get by with rabbit ears?


Tell me something good!


Gerald
 

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I, too, have the NEC LT150 and the Fusion HDTV II. Although my system (P4 2.66 Ghz) is plenty fast enough for "software" decoding, the Fusion card seems to have trouble with 720p signals.


One of the supposed advantages of the Fusion card is that it uses your video card as the output device, so the scaling is done by your computer, rather than being limited to the options on the HD card. I assume you have your resolution set to 1024 X 768. If so, the Fusion card will tune the signal, the computer will scale it, and send it to the LT150. Most cards, apparently, have the HD output coming directly from the card and, unless the card can output the same resolution as your projector, you can have problems.


As for the "real world" use of the Fusion card, I live in Portland Oregon, and the local ABC station broadcasts 720p and the Fusion card "hiccups" about every 10 seconds. That is, the picture freezes for a portion of a second, or as long as a second, then picks up at the new "live" point again. This has been particularly annoying during sporting events. A pass is thrown, then a freeze, then the play is dead and I'm left wondering what happened.


1080i signals look fine, if the signal strength is strong enough, but I still have an occasional "hiccup", particularly when recording the channel. I would GUESS (and it's strictly a guess) that the increased load of trying to record the channel at the same time that I watch it results in the "mini-hiccups" that I've seen. There does not seem to be a way, currently, with the Fusion HDTV II (and the most recent software, version 2, which does NOT ship with the card, but can be downloaded at www.dvico.com ) to record an HDTV show unless the DVICO software is running and the video is being displayed. In other words, I don't see a way of using it as a PVR or digital VCR. It only appears to be able to record a show that you are actually watching, or set it to record a show in the future, but leave the software running so you can't really use your computer for other purposes when it starts recording.


In reading various posts on this forum, I've seen other people with similar problems with the Fusion card. I have 100% signal strength (rarly dropping below 98%) on the channel that has given me problems, and I have tried the card using DxVA and not using DxVA (hardware accel.) and the picture quality is better with DxVA turned on. The motion is smoother. I know that the DVICO site says that a P4 1.66 or so is adequate, but my system is significantly faster, with 512Mhz RAM (I forget the speed, but much faster than DVICO says is necessary) and I still find that hardware accel is generally necessary. Your video card should take care of that, just fine.


The Fusion software still needs work, in my opinion. You are supposed to be able to change channels by using the scroll wheel on the mouse (if you have a scroll thingy on your mouse). Unfortunately, that isn't dependable. I've rarely been able to get it to work when changing from channel 10-1 to channel 10-2 and, OFTEN, it refuses to work at all. The "shortcut" keys that it seems to refer to (if you right-click, it shows several features, such as "Display Size (W)" and "Aspect Ration (A)" which imply that Control-W or Alt-W or Control-A or Control-A would bring up the approprioate menu, or toggle between various options, but such key combinations do nothing. Furthermore, there is no way to set each channel to separate configurations, such as stretching 480i channels that are "squished" to 16:9 resolution, but should be 4:3 without "squishing" all stations. You have to manually set each station to the appropriate format when you tune it in. This can be annoying because many stations change aspect ratios throughout the day, depending upon the programming they are showing at the time.


For the record, I have been so frusrated with the Fusion HDTV II card (I've only had it a little over 2 weeks) that I ordered the MyHD card to replace my Fusion card, but I've kept the Fusion card until the new one arrives. The MyHD card is "supposed" to be here, tomorrow, according to the DHL shipping "due date". I'm anxious to try it and it's software.


After I get a chance to use it, and see how it compares, I'll post a follow-up, if you'd like.
 

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I have had hiccups with the Fusion Card on various occasions. But as my PC is a Shuttle XPC and I have an LCD monitor available, I take it on the road like a laptop. What I have found is that the hiccups must be related to the incoming signal. Here at home in Louisville, I get ABC in perfectly with a Silver Sensor antenna. On the road this week in Kansas City, I actually had 100% signal strength but a choppy picture on ABC. I am guessing it must be related to interference of some sort.


But it is strange. In Louisville, 78% signal strength, perfect picture.


Kansas City, 100% signal strength, choppy picture.


As for scaling, here in Louisville I run my little XPC to a 21" analog most times at 1152 x 864, sometimes to my Samsung 172W widescreen LCD at 1280 x 720, and sometimes via the component dongle to my 65" Mitsubishi at 1776 x 1000. I have them all working at various resolutions (thanks Karnis for help with the TV). In my opinion, the Fusion card perfroms scaling fantastic!


Chris
 

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I think the Fusion card is great for scaling. Since it uses your computer's video card, it can scale to whatever resolution your video card can handle. The MyHD can only scale (or so I understand, not having seen it yet) to certain resolutions, but 1024 X 768 (like the NEC LT150) is one of the options of the MyHD card.


I've also heard that the HD broadcast stability is critical when using the Fusion card. I haven't had much in the way of problem with the Fusion card and most local HD channels. Just the 720p stuff. I read, on some post on this forum, that the Fusion sofware is trying to deinterlace 720p signals, which were, as the "p" in 720p suggests, progressive in the first place. I don't know if that's true, but I've seen posts of others with Fusion problems similar to mine.


I don't mean to sound like I'm complaining about the Fusion card. That's not my intent at all. I've been mostly happy with it, with the STRONG exception of the local ABC affiliate which is the only 720p (and, unfortunately, Monday Night Football, even though I'm not a big football fan, but don't tell my brother, the high-school football coach) and various software issues that I mentioned in my original post. The software does not seem but be "mature", yet, but DVICO has made several enhancements so far this year.


I've had enough concerns with the Fusion card that, as I mentioned, I've ordered the MyHD 120 card. I hope to know, by tomorrow evening, if it arrives tomorrow, how it compares.
 

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I have the LT-150 and the MyHD card. It is a great combo. The LT-150 will handle other resolutions from the MyHD than than the 1024 by 768. But there is no real advantage in doing so as the LT-150 just down/up converts it to its native XGA resolution.


I have run both the MyHD and the Fussion II. I prefer the MyHD. PQ just seems a little sharper. The video card that I am using is the 9500 so that should not be the cause.


I think the next release of the software for the Fusion will try to fix the 720p problems.
 

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Quote:
Originally posted by tandrb


As for the "real world" use of the Fusion card, I live in Portland Oregon, and the local ABC station broadcasts 720p and the Fusion card "hiccups" about every 10 seconds. That is, the picture freezes for a portion of a second, or as long as a second, then picks up at the new "live" point again. This has been particularly annoying during sporting events. A pass is thrown, then a freeze, then the play is dead and I'm left wondering what happened.

As I mentioned in another thread, most of your issues with this station have nothing to do with the Fusion software having trouble with 720p, but rather that the Portland ABC station is currently having hardware problems that are causing errors in thier broadcast. Here is a quote from the station engineer as posted over in the HDTV reception forum.


"We are having some problems with our HD transmitter, so the audio break-ups and freeze frames are real. We are limping along on part of our transmitter while the rest of it has been sent back to the manufacturer for evaluation.


I hope to have better news soon.."


Now, it may be that some of the other HDTV tuner cards are better at handling errors than the Fusion is. My experience is that the Fusion will freeze frame for most errors, whereas other cards may just throw a few ugly blocks on the screen and keep going. I have also noticed that the DXVA decoder freezes frames for much longer than the full software decoder in the Fusion software.


Anyway, not to say that the Fusion software doesn't have its share of problems, however, I don't believe that 720p decoding is necessarily one of them.
 

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A couple of things here:

--Radeon 9800--


Isn't that is one of the cards that exhibits the famous "Fusion jitter" due to an ATI driver problem?


The Fusion card dislikes sharing an IRQ with any other device. Some motherboards link IRQ sharing with ACPI, so that ACPI must be turned off.


I too, have found that the stations can do some strange things with 720p.
 

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I have a LT-150 and a MyHD card. I connect the loopback cable to the video card, and then VGA to the projector. I also have a HD-cable box for ESPN_HD. That connects via component cable with a hd-15 connector on one end. HD on both sources looks great. The only advantage to the component connection I see is that you are able to use the aspect ratio and other setup options in the LT150 menu that are unavailable via VGA
 

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Discussion Starter · #9 ·
Thanks for all the responses guys. I have some more questions:


Happystick: how do you switch sources (pc vs HD sat) going to the LT150? How do the aspect ratio etc. help you when you use component ie: does the resulting picture look better? What "res" does your HD receiver send?


e vey: can you post a link?


For those of you with the myHD card: does the pass-through cause any noticeable signal noise on VGA sources (software DVD player, for intance?)


For HARDWARE cards, am I correct in assuming there is some sort of software that controls the presentation of HD signal vs. the PC desktop? The only difference between hardware cards and the Fusion is that decoding the ATSC signal is done in hardware?


Do the hardware cards send component signals as well as VGA?


and one question to re-ask:


How do you calibrate for HDTV material? Is this done with the hardware overlay? The HDTV software? Is there a good source to calibrate with (similar to Avia), or am I going to have to be eyeballing it?
 

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I saw Yablo's post regarding problems with the local ABC station, but when I went to the local HDTV "store" they had the same station tuned in, and it looked fine.


Based upon that, I am guessing that it is something to do with the error correction in the Fusion software and/or card.


Between that problem, the little software glitches, the little freezes on other stations, and the difficulty recording (in fact, when I record a station, and watch it back, the same glitches occur at the same points which implies that the problem in the stream was recorded, then duplicated later) I've decided to try the MyHD card and see if it handles these issues better.


In the posts I've read, it does.
 
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