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Discussion Starter · #1 ·
OK, so I feel like i've read every post in relation to QAM vs 8VSB. I know the two are incompatible. I don't know if my local (Hopkins, Minnesota) TWC does 256 QAM or not for HBO and Showtime; but I'm betting they do. I've looked high and low for some sort of box that will allow me to demnodulate / transcode / modulate (I don't know what word i should be using) QAM to 8VSB so i can feed the signal to the myHD cad i'll be getting some day (when the shipment that has my order in it, arrives from Jupiter).


It seems that the only card in the commecial US market that has a QAM tuner is the AcessDTV (and the old Hauppage), but neither of them has the software to do anything with it. I'm feeling quite fed up with the whole scene, but yet there might be hope.?


I saw this card (at a Korean? Mfg. website). Info is in a PDF, with not much info at that, but it seems to ouput a transport stream, which could(?) be used by a myHD or a HiPix. I also comes with windows 2000 WDM drivers, so its supported by a solid(ish) OS.


So. could the TVB140 be used as a cable box? Could you split the signal on its way in, so that You only need to use this card for the HD chanels and continue using the myHD or HiPix for your analog cable channels? Will this thing cost less than my bicicle, my cat and my microwave (combined, of course)? Could we gang up on these guys and convince them to sell us a bunch?


So if the answer is yes, how do we get them? I'd be willing to act as an organizer for a large purchase, but mostly I just want to find out if us folks who aren't hip to the Dish have any options?
 

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MyHD card chip for 8VSB reception also supports QAM, but it is not implemented. You should suggest this to MyHD maker to add support for QAM. All they need to do is write updated software.
 

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Matt, are you using one of the 3100HD boxes from TWC? I tried to pry some information out of them regarding the firewire port but didn't have any luck either at TWC or SA directly. They tried to tell me that it isn't an output but I find that hard to believe.


I've kind of resolved myself to the fact that I'll have to wait for one of the new SA 8000 PVR units. Who knows when it'll be released, though.
 

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FYI:


There are some 8VSB modulator cards that fit

in a PCI chassis. Sencore demo boxes are basically

a PC with a PCI card that outputs 8VSB. I don't

know who builds them or if they are available for

sale anywhere but they do exist.


I think there are some QAM receiver cards

(from Broadlogic for instance) that could receive

non-encrypted channels from your cable system.

If you had the right software to tune and save

those streams as ATSC data on your hard disk then

you should (theoretically) be able to open them

in "file" mode on a card like the MyHD and play

them back after they are recorded.

Viewing them in realtime would be more difficult.


I have no idea if your (or any) cable systems are

encrypting their QAM or 8VSB HD channels. If they

did then you would likely be stuck using only their

set top box to view the channels.
 

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Matt_EtheC:


I think you will find encryption of the signal via SA's "Powerkey Conditional Access system" (secure digital service using RSA eycryption) may well stop you from doing what you want to do (may depend on your cable co). Note that some owners of sets with integrated tuners that can decode 256QAM have reported they cannot get the premiums off their cable. I am not sure they can decode all the standard digital tier programs either.



mlomker:


I suspect there are ports built into the box that are not currently supported by the OS installed or supported by the various TWC units. The spec sheet I have for the 3100HD lists a USB port but no Firewire. This goes along with reports elsewhere here at AVS that said the box was designed before IEEE1394/FW was a player.


Bruce
 

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Discussion Starter · #6 ·
Quote:
Originally posted by CKNA
MyHD card chip for 8VSB reception also supports QAM, but it is not implemented. You should suggest this to MyHD maker to add support for QAM. All they need to do is write updated software.
I thought that the scuttlebutt on the myHD card was that it did NOT support QAM


I have not yet ordered the HD cable channels as i'm waiting to find out if this is possible. I see no point to having the channels without recording capabilities, since I rarely will be able to watch things as they air. But i do know that my TWC installer told me the only way i'd be able to record is with a computer since they didn't have any outputs on their boxes. I've never seen one of their boxes. Do they have firewire outputs on them? The specs aren't clear anywhere.


PVR - thank you for being so helpful in both of the threads, sorry i made a seemingly duplicate one, I just was getting the feeling that 169 times involvement in the other was scaring the cable knowledge away.


I have written a letter to TWC local to find out about what i might be able to do. I intimated that there were 'quite a few' customers who were turned away to the dish, to get the premiums due to their relative uselessness as live broadcast signals (unless you're a college student, up at all hours), and that with the dish, personal recording was possible, but if they made it easier to record, they might get people like me to sign up, and not just me.
 

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TWC HD generally is the least expensive way short term to get any HD. Most TWCs charge around $5/mo for the HD cable box though you must also subscribe to their digital tier. HBO and SHO are avail too. And if not now then soon one might be able to get some/all of the commercial stations (or PBS) .


If you get a STB (or the HDTV computer card) then what is available OTA wise you can get (and the card may let you record the OTA stuff). Satellite is the other main choice of course; generally has an OTA receiver built in or availble but has its own recording problems. The 169time is working I believe on the sat record solution. Still; it is frustrating not to be able to record and timeshift DTV/HD.


SA has pdfs on their site (in the Explorer club) of their manuals (requires box serial number to access..dumb). Briefly, the 3100HD rear panel has: YPrPb component out, S-Video out, Composite video out, IR port out (vcr commander), Digital Audio out (coax with RCA), L/R audio out, cable out (analog), cable in, and an optional RF bypass module (?). The front panel has a single USB port and a Smart Card Slot.


Bruce
 

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Hi!


I'm sorry to have to say this, but there will be little point in developing a QAM256 version of the MyHD, or any other such product. As Bruce points out, the problem is what the cable folks call "conditional access", which we essentially call copy protection. In the Scientific Atlanta system it's PowerKey, and in Motorola/General Instruments it's Digicipher. While a few cable companies may have transmitted HDTV over cable using 8VSB initially as a short-term expedient, the chance of finding a cable company that goes to the effort of remodulating and rate-shaping a channel into QAM256, then transmitting it without encryption is essentially zero.


Asking the MyHD developers to go through a ton of effort that will very probably wind up being useless may not be the best use of their time... Your best bet will be to watch for the upcoming HD-capable set-top boxes with internal PVR capabilities, such as Motorola's (/digeo's/Moxie's) BMC-9000, and Scientific Atlanta's Explorer 8000. I apologize, but that's the state of cable.


Best Regards,

MarkF
 

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Quote:
I'm sorry to have to say this, but there will be little point in developing a QAM256 version of the MyHD, or any other such product
I do not agree. Yes premium channels may be encrypted but many basic channels will not be, like off air channels. It is like today with analog cable. Most cable companies pass off air and basic channels unscrambled. As a matter of fact many TWC systems re modulate off air signals into QAM256 and people with Mistsubishi sets which have QAM tuners can see those channels. It would not take too much to add QAM support to MyHD because NextWave 2000 chip already is able to do that. All they have to do is enable it.


BTW, pretty much all Mistsubishi HDTV sets with tuners can receive QAM64/256 and new Samsung STB with firewire output will have 8VSB/QAM64/256 tuner built in.
 

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Hi, CKNA!


Whoa - I stand corrected! I'm aware that many cable companies have transmitted 8VSB HDTV in the clear, but until now, I'd never heard of a single QAM256 signal being transmitted in the clear. Not to disagree further, but are you sure that the signals that folks are receiving with their Mits sets aren't just 8VSB? Anyway, my apologies!


Cheers!

MarkF
 

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Here is the situation in NYC with TWC. When they first started transmitting HDTV, the used 8VSB for all their channels. That included HBO. Anyone with an OTA antenna could recieve it.


Then they switched over to QAM256. There was a brief time when they had HBO in both 8VSB and QAM256. People that saw it (not I) claim that 8VSB looked a little better.


Anyway, that was brief. They killled the 8VSB signal on HBO, and Showtime. Only the free channels were still 8VSB. After 9/11, the only channels they had in HDTV were CBS, HBO, and SHO. CBS was in both formats, HBO and SHO wree in only in QAM256.


A few months later (Feb), they added NBC via a fiber link to the NBC main office here in NYC. The modulation of choice- QAM256 encrypted. So, here was a free channel, added very recently and they chose to encrypt it. That doesn't look good for the future. Of course, once HDTV really becomes popular, they may legislate that free channels must remain unencrypted. But that will probably be a long time off.


I think our best bet (immediatelly) is to record off of the component wires. The only 2 options are WVHS, or a capture card. Both are very expensive at this point. Our next best bet is the Explorer 8000 with a built in PVR. Then firewire. I say firewire last b/c TWC has committed to the Explore 3100, and next the 8000. Neither have firewire. We are stuck with whatever they give us.
 

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Discussion Starter · #12 ·
If its only an issue of an encryption key, doesn't the law that forbids forcing us to pay for something when we have to use it to recieve the channels, mandate that we be allowed to use whatever we want as a cable box, as long as we're paying for the channels? With that in mind, how hard would it be for MIT to develop A cipher program that could provide a (I EMPHASISE) legal key decrpyt, that TWC could provide us with? It doesn;t strike me as a 'waste of time', since it really just seems like an issue of developing a software solution to match the three or four hardware solutions they have. Copy protection can easily be put into the datastrream forbidding multiple copies. I guess i don't understand why these cable types (and other entertainment providers) don't seem to grasp the concept that if they jealously protect their content to the point of not allowing people to record movies broadcast on pay cable, simply in the name of 'piracy concerns' that they're only enabling the black market devices that do waht i'm looking to have done legally. Its just kind of sad.
 

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Discussion Starter · #13 ·
OK. The new question is. Consider the 3100HD. I has an output labled 7 - Connect to cable output of TV/VCR (in the PDF manual). What exactly is being ouput there? And what is to stop a person from altering the output a little to include the unmodulated QAM signal? I'm assuming (geting the ass sign out ready to hang around my neck) that the signal it puts out is 8vsb in nature so any old schmoe would be able to watch their 'digital channels' on their super (color no less) TV with only an RF input (one of those 'cable ready' deals). Since its RF, its likely tuned to channel 3. If a standard TV tried to tune an HD signal it would just look like garbledeyguk to the old TV anyhow, So what would be the logic of preventing the output of just the HD channels. Obviously I'm not the first pertson to think of this, but maybe they're just new enough that people haven't looked inside to find out it's just a jumper or something?

Perhaps I'm a moron. It's OK I'm used to it. Edit: wouldnt it be great if i got all my thoughts out the first time, just once?
 

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I just did a search on the 3100HD and it sounds like

the RF outputs are analog standard def only

(not 8VSB/HD).


From http://www.minnesotaroadrunner.com/s..._hdtv_faq.html

"What kind of connections do the HDTV terminals (Explorer 3100HD) support?

YPrPb and RGB component for high definition video,

S-Video, composite Video, and RF (cable out)

for *standard definition*, stereo analog audio, and

Dolby Digitalâ„¢ audio (coaxial)."
 

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As you may have read my postings in other forums, it's not design of 3100HD that we should be furious about.


It's SA and our cable companies. They configure 3100HD box so it doesn't output anything on RF, Svideo and composite outputs for all HD programming, and some SD too.


Here's example: on Rogers HD lineup, HDTMN is blanked on mentioned outputs ONLY when there is HD content playing. Otherwise, when there is a shining blue M logo (in between movies), your SD outputs will work. So it's not that Rogers decided to mark that channel banned from having SD outputs, it's only when HD content is being played.


I thought it was inability of the box to downconvert 1080i signals to 480i, but it's not. For example, take HDCBS. You would think that SD outputs would be blanked ONLY during airing of some new HD show (Like Raymond) and would go back to being active (like on HDTMN logo) during regular SD broadcast, like 11pm news. Wrong! Those outputs are dead all the time on HDCBS, even when SD programming is coming in.


As a conclusion, SD outputs are being blanked based on what content provider or cable company wants us to see in SD, not based on type of input (SD/HD) or channel designation (280-288 or others).


If you look closer at other HD-capable devices you will see same fear of litigation implemented everywhere. My tv, for example, disables composite monitor output when input is coming through composite inputs. Manufacturers and cable companies are aware that it would be very easy to make DVD-like quality recording from S-video output during airing of HD movie on HDTMN (HD HBO) and they want to stay away from legal troubles.


Another big issue is that our cable providers use RSA encryption and custom setup to force consumers to use proprietary (e.g. nonstandard) cable boxes to deliver digital programming, rendering QAM tuners unusable. Even worse, if you ask your cable co to replace your SA Explorer box with another brand (say, Motorola) they will say it's not possible. Such lack of choice does not exist in any other consumer electronics field today. Your music store does not force you to use only one brand of cd player, and you are never forced to use only one brand of cell phones.


It looks like cable box manufacturers and their cable companies created monopoly for digital and HDTV distribution that even Bill Gates would envy.

We are locked in and at their mercy for pricing, choice or features. And unless someone comes up with modification for 3100HD that would allow HD recording and force competition with the original manufacturer we are not very likely to see SA come out with Explorer 3100HD with firewire outputs any time soon. Why mess up a good thing like monopoly?
 

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Discussion Starter · #16 ·
Quote:
Originally posted by AlexG


It looks like cable box manufacturers and their cable companies created monopoly for digital and HDTV distribution that even Bill Gates would envy.

We are locked in and at their mercy for pricing, choice or features. And unless someone comes up with modification for 3100HD that would allow HD recording and force competition with the original manufacturer we are not very likely to see SA come out with Explorer 3100HD with firewire outputs any time soon. Why mess up a good thing like monopoly?
So, with those tests, did you have the cable pugged into another HD tuner?

Has anyone just tried that? Taking the Rf output on a 3100HD and plugging it into another HD tuner, tuned to channel 3? That's all we need. A modification of the guts that puts an 8vsb signal out the rf connector on channel 3/4. Its so simple, it drives me batty.


So, what can we do? What are the odds, it's just a jumper or two. Who's got some money so we can sue these guys? I'm not content to sit here and take it, but ALAS I am too clumsy to open up a box and poke around to find out how i could get this legal signal out of there in the form i want, to do something that has legal precedent and actually put value into my purchase of HD premium cable services. What is up with all this prior restraint garbage? Just because I could make copies and hand them out doesn't mean I WILL. It's painfully obvious that this sort of thing is what drives people to stealing. (That and the general lack of interest in paying for anything)
 

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Quote:
Originally posted by Matt_EtheC



So, with those tests, did you have the cable pugged into another HD tuner?

Has anyone just tried that? Taking the Rf output on a 3100HD and plugging it into another HD tuner, tuned to channel 3?
No, I didn't try that, I don't have another HD tuner around but someone who has might try it and let us know how it went.
 

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Discussion Starter · #18 ·
(Not that I think it's going to work, but wouldn't it be a trip?)
 

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I have heard from a very reliable source (the father of HDTV) that the difference in modulation between QAM and 8VSB is very slight. BUT, we still have the encryption thing to get past.
 

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There is big difference between 8VSB and QAM. QAM is based on OFDM where it has many carriers carrying data. 8VSB is single carrier system.
 
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