Author Topic: Straight answers about digital cable  (Read 3444 times)

Afkpuz

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Straight answers about digital cable
« on: January 06, 2009, 07:04:11 am »
Ok, I know that I am very confused about digital cable.  I thought it might be good to lay down some information in the wiki about what the user needs to know when purchasing tuners, particularly, the compatibility of tuners with their cable service.  I'd be very willing to do this, but need some clarification on a few points.  Here is the gist of what I know and will be putting into the wiki.  Please comment if I have some information wrong or left out something important.  After it looks like the posts have died down, I'll make the wiki page.



Free, OTA, or Broad cast TV: This refers to the free stations that are broadcasting over the air(OTA) and are picked up with an antenna (rabbit ears).
This tv signal will be changing to digital in feb (in america at least.  Little help on other country standards would be appreciated)
1.) TV's using this signal must have digital tuners built in, or user must purchase converter box after febuary

Cable from a provider: Any type of tv signal which is purchased through the a cable company.  Comcast is the main monopoly one here in america and I'll focus on them since I use them.  Others would be encouraged to add information on other cable companies once I get the wiki area up and running

1.)ANALOG Comcast, at least, will continue to provide analog television to it's subscribers indefinitely.  Nothing needs to be done for this.  No converter boxes or new tv's will need to be bought.
      A. NTSC computer tuners are the ones which can read this tv signal.  I'll include links to compatible cards and make sure to mention LMCE compatibility as well here.  This cable signal is unencrypted?(Need input here)


2.)DIGITAL Here's where I need help.  This is what I understand after researching and chatting with comcast's unhelpful online staff.
      A.  In order to tune comcast digital cable of any kind, a set top box is required.  (I'm not sure about this, but some comcast techie tried to convince me of this.  I was under the impression that only the High def, premium, on demand, etc channels required a set top box.  What about the low channels from comcast which are digital, like normal old discovery channel in digital?  Need some input here.)  This is due to comcast's signal being encrypted?  Are all comcast channels encrypted and therefore unusable by computer tuners??  Please comment on this 
             i. The work around involves getting a cable box with firewire output and recording that stream while IR blasting for control of channels.  I know this has been done by some users for those high definition set top boxes
      B. Free digital stations are mostly (maybe always??) broadcast in the QAM format.  Saying "clear QAM" refers to unencrypted QAM siganls.  Look for tuner's advertised for clear qam for this form of cable.  This form of digital cable is easily captured in LMCE


So, my main area of confusion is the simple digital channels from comcast.  Let's say that I receive channel 32 (discovery channel in my area) in digital format from comcast.  It's part of the basic plan, not free over the air, and it's not pay per view or an extra channel (like hbo).  Can LMCE watch that station?  That's what I need to know and then I should be able to get to work on the wiki.  Also, I'd love some testimonies of you users who have listed their set ups in the wiki would be great!  Which types of TV signal have you been able to tune?  thanks guys









Seeker

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Re: Straight answers about digital cable
« Reply #1 on: January 06, 2009, 12:10:59 pm »
In Denmark, the signal changes on 31. of October.
Moste danish cable providers (all?) continue to supply analog signals.

2A
You can get a DVB-C cards with CAM-card interface. You only need a set top box for cable provider specific services as ppw and on-demand.

2B
I'm not sure here, but I think that the difference between analog and digital is that you get everything on digital, but can only access the channels that your CAM module supports (much like satellite reception). The analog cable is restricted before the signal enters your home, thus there is no need for further limitations, but if the signal carries all channels your provider will certainly make sure that you don't receive anything you haven't paid for. As for clear QAM, I'm still not sure that you will be able to receive without a CAM module, but I have no way of testing as I haven't gone digital myself yet. My service provider (YouSee) at least makes a big deal out of telling that a digital subscription is only good for one TV or set top box.

skeptic

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Re: Straight answers about digital cable
« Reply #2 on: January 06, 2009, 04:47:27 pm »
Afkpuz - I have comcast and I've spent some time on the phone with them getting these answers as well. 

First, firewire just doesn't work very well.  It's prone to crashing, isn't 100% reliable, and takes some work to setup (not plug and play with LMCE at the moment).  On the other hand, with firewire you don't need an IR blaster, it changes the channels via firewire.  On the plus side, if you are careful and never let your cable box tune to an encrypted channel it works ok and the video quality is great.

Analog - as far as I know you will not be able to view unencrypted premium channels, only channels 2-99.  They have stated they will provide analog for at least 1 year, but no promise or words how much longer if at all.

Digital (what I have) - According to the tech I spoke with and verified by testing, you do not need a set top box for channels 2-99.  Just like Analog, channels 2-99 are unencrypted.  I have verified this with my HDTV's built-in QAM tuner.  As of right now, most sub 99 channels in the Digital package are still broadcast in analog.  However, there are some digital and even some HD channels in the sub 99 range that are broadcast in clear QAM.  For example, channel 2 is analog SD, channel 2-1 on my TV is the high-def version of the same thing.  On the cable box, it is channel 654 (IIRC). 

Unfortunately, the only LMCE compatible QAM tuner in the US that I know of is HDHomeRun and it is digital only.  Until Comcast is broadcasting 100% digital I don't know of any single tuner that works for every channel.  If/when the new Hauppauge boards are plug and play with LMCE they would work great for mixed analog/digital signals, or if Comcast starts broadcasting 100% digital I can go with HDHomeRun.  Until then, the only reliable method I've found is to capture the s-video out from the cable box and control the box via USBUIRT.

What we really need is cablecard support so we can get ClearQAM and encrypted QAM, but I think the cable companies have pretty much killed that.

tkmedia

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Re: Straight answers about digital cable
« Reply #3 on: January 06, 2009, 05:21:37 pm »
I think skeptic hit on most points there are linux compatible clear quam  cards we just need to create templates for them however encrypted channels will need to be captured. I am going to try to get the hdpvr tested for 0810  as it has component in and will be able to record from cable boxes.




Tim
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nascarfan1956

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Re: Straight answers about digital cable
« Reply #4 on: January 06, 2009, 06:43:29 pm »
Ok, I know that I am very confused about digital cable.  I thought it might be good to lay down some information in the wiki about what the user needs to know when purchasing tuners, particularly, the compatibility of tuners with their cable service.  I'd be very willing to do this, but need some clarification on a few points.  Here is the gist of what I know and will be putting into the wiki.  Please comment if I have some information wrong or left out something important.  After it looks like the posts have died down, I'll make the wiki page.



Free, OTA, or Broad cast TV: This refers to the free stations that are broadcasting over the air(OTA) and are picked up with an antenna (rabbit ears).
This tv signal will be changing to digital in feb (in america at least.  Little help on other country standards would be appreciated)
1.) TV's using this signal must have digital tuners built in, or user must purchase converter box after febuary

Cable from a provider: Any type of tv signal which is purchased through the a cable company.  Comcast is the main monopoly one here in america and I'll focus on them since I use them.  Others would be encouraged to add information on other cable companies once I get the wiki area up and running

1.)ANALOG Comcast, at least, will continue to provide analog television to it's subscribers indefinitely.  Nothing needs to be done for this.  No converter boxes or new tv's will need to be bought.
      A. NTSC computer tuners are the ones which can read this tv signal.  I'll include links to compatible cards and make sure to mention LMCE compatibility as well here.  This cable signal is unencrypted?(Need input here)


2.)DIGITAL Here's where I need help.  This is what I understand after researching and chatting with comcast's unhelpful online staff.
      A.  In order to tune comcast digital cable of any kind, a set top box is required.  (I'm not sure about this, but some comcast techie tried to convince me of this.  I was under the impression that only the High def, premium, on demand, etc channels required a set top box.  What about the low channels from comcast which are digital, like normal old discovery channel in digital?  Need some input here.)  This is due to comcast's signal being encrypted?  Are all comcast channels encrypted and therefore unusable by computer tuners??  Please comment on this 
             i. The work around involves getting a cable box with firewire output and recording that stream while IR blasting for control of channels.  I know this has been done by some users for those high definition set top boxes
      B. Free digital stations are mostly (maybe always??) broadcast in the QAM format.  Saying "clear QAM" refers to unencrypted QAM siganls.  Look for tuner's advertised for clear qam for this form of cable.  This form of digital cable is easily captured in LMCE


So, my main area of confusion is the simple digital channels from comcast.  Let's say that I receive channel 32 (discovery channel in my area) in digital format from comcast.  It's part of the basic plan, not free over the air, and it's not pay per view or an extra channel (like hbo).  Can LMCE watch that station?  That's what I need to know and then I should be able to get to work on the wiki.  Also, I'd love some testimonies of you users who have listed their set ups in the wiki would be great!  Which types of TV signal have you been able to tune?  thanks guys










OK....As to your particular situation I can shed some light on the situation.  Comcast (NOT a monopoly, both the FTC and the courts have confirmed this) is in the process of migrating some of the basic lineup (channels 30-99) to digital format in order to reclaim bandwith and offer more content, and is offering a specific STB for this purpose (referred to as a DTA) at no cost to subscribers.  The assertion that a STB is REQUIRED to tune ANY digital channels is false.  Any TV equipped with a QAM tuner should be able to tune digital channels on its own.  A cable card would be necessary to tune encrypted channels, but unencrypted channels (which include the local HD channels) should be able be received with the QAM tuner.

skeptic

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Re: Straight answers about digital cable
« Reply #5 on: January 06, 2009, 07:19:30 pm »
Only converting channels 30-99 to digital?  May I ask where you got this?  It's different info than what I was told, and if I were told wrong then I need to re-evaluate my plans to go with HDHomeRun (no NTSC therefore no channels 2-29).

Does this hold true for their Digital packages as well or will their digital packages truly go all digital sometime next month?

Afkpuz

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Re: Straight answers about digital cable
« Reply #6 on: January 06, 2009, 07:43:54 pm »
So if I understand correctly, comcast channels 2-99 could be tuned with a digital tuner, such as the HDhomerun.   Is this an accurate statement?  Is there anyone who has comcast digital cable and is tuning channels 2-99?

skeptic

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Re: Straight answers about digital cable
« Reply #7 on: January 06, 2009, 09:03:45 pm »
So if I understand correctly, comcast channels 2-99 could be tuned with a digital tuner, such as the HDhomerun.   Is this an accurate statement?  Is there anyone who has comcast digital cable and is tuning channels 2-99?
Whether will include all of 2-99 or just 30-99 was my question.  :)  All of this is in progress, the switch hasn't happened yet.  Comcast appears to be timing this with the OTA conversion.  At the moment, I can verify that you can tune SOME digital channels throughout the 2-99 range including my example 2-1 being the HD digital version of channel 2 (654 on the cable box), as well as a couple channels in the 30-99 range such as E! which is digital SD on channel 59 (not 59-x) which is also 59 on the cable box.

If some of the stations in the 2-30 range do not go digital, I'll probably have to go with something other than HDHomeRun, at which time I'll be bugging Thom about how to correctly create and sqlCVS a device template as soon as the HVR-2250 (dual tuner) card is supported by Myth.

edit:  Just to be clear, I have Comcast digital cable, a PVR-150 (analog only), and a TV with a QAM tuner.  Getting off the STBs is going to be a priority for me next month after the switch so I have been looking into these questions lately.  Getting a correct straight answer out of Comcast is a challenge. 
« Last Edit: January 06, 2009, 09:17:09 pm by skeptic »

colinjones

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Re: Straight answers about digital cable
« Reply #8 on: January 06, 2009, 09:16:14 pm »
A little general background that might help flesh it out.

When you say "changing to digital in feb" you need to distinguish what they call ASO (Analogue Switch Off) - all countries that are going, or have started digital services plan to switch off the old analogue services to free up that spectrum. Some countries have already done this, other plan to in the next few years. But digital services are already running in the US, so Feb is probably the ASO, although it is very unlikely they will do the whole country in one hit!

Digital is broadly split into 3 standards world wide. ATSC is the standard used for terrestrial/cable services in the US, also in Canada, a couple S. American countries and South Korea. Japan uses a different standard called ISDB for terrestrial and Brasil uses a variation of this. The rest of the world (except China) either is using DVB-T or plans to use it for terrestrial services - all Europe, Asia, Australia/NZ, S. Africa and various other African and Middle Eastern states, S. America, Russia, Eastern Europe and the Balkan states. In most locations that use DVB-T for digital terrestrial services also use DVB-C for digital cable services. DVB-S and DVB-S2 is the most common digital satelite service format around the world (and interesting is also used my some US providers like Dish).

All of these services can be "FTA" (Free To Air) or unencrypted, or encrypted - if encrypted, you need a decryption box, but in some countries that doesn't necessarily imply a pay-for service, but usually it does. Decryption for DVB type transmissions is usually by a standard like CAM/CI/Irdeto using a decryption module/smart card provided by the TV company. In some cases you can use your own hardware (like a PCI card) and the TV company's module thus meaning you can integrate completely with LMCE, many other providers only allow you to use their STB which means you can't feed the stream directly into LMCE digitally - this can be gotten around, but note is illegal! So failing that you need to sample the video/audio using an analogue card and feed that in instead or in limited cases (as mentioned) a firewire port will give you the unecrypted/uncompressed raw digital stream.

Neither SDTV nor HDTV imply free or pay services, they can be either - and as mentioned, in some case just because it is encrypted doesn't mean that it is a pay service (but usually does!) Analogue is rapidly dying in all countries that are already transmitting services, as authorities and providers want to free up the spectrum/bandwidth.

skeptic

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Re: Straight answers about digital cable
« Reply #9 on: January 06, 2009, 09:49:29 pm »
This thread, or at least my replies, are centered on the provider Comcast in the US per the OPs comment "Comcast is the main monopoly one here in america and I'll focus on them since I use them" then going into Comcast specific topics.

Much of what I posted doesn't apply to other providers in the US, let alone other countries.  I/we probably should have been more clear.

nascarfan1956

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Re: Straight answers about digital cable
« Reply #10 on: January 06, 2009, 11:13:45 pm »
Only converting channels 30-99 to digital?  May I ask where you got this?  It's different info than what I was told, and if I were told wrong then I need to re-evaluate my plans to go with HDHomeRun (no NTSC therefore no channels 2-29).

Does this hold true for their Digital packages as well or will their digital packages truly go all digital sometime next month?

I know this to be fact.  How I know this I'd rather not say publicly as I'm bound by certain rules regarding that subject.  The current plans as they exist are to migrate 30-99 to all digital format in the first half of 2009.  Timing is not specific as different markets are in different stages of upgrading plant and equipment, and it will take some time to get the necessary equipment into customer's hands.  2-30 which comprise the "limited" lineup which is mostly of the local SD broadcast stations and the public access channels will remain as analog content.   Currently all of the limited and basic channels 2-99 in most markets are simulcast in digital form (and have been for some time) and when received through a STB or QAM are received in that format. 

tkmedia

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Re: Straight answers about digital cable
« Reply #11 on: January 07, 2009, 05:33:50 am »
I have comcast in New England and I have a hd homerun....

From my experience I get the major stations NBC ABC ETC in clear quam .... CPTV and about 20-30 stations total.



Tim
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slow_learner

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Re: Straight answers about digital cable
« Reply #12 on: January 07, 2009, 06:24:37 am »
I live in San Francisco, and get pretty much the same channel selection using my HDHomerun that Tim gets. The major stations, and local community channels.  I cannot tune the 30+ cable channels, even though I'm signed up with comcast's digital package.

shane

colinjones

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Re: Straight answers about digital cable
« Reply #13 on: January 07, 2009, 06:30:30 am »
This thread, or at least my replies, are centered on the provider Comcast in the US per the OPs comment "Comcast is the main monopoly one here in america and I'll focus on them since I use them" then going into Comcast specific topics.

Much of what I posted doesn't apply to other providers in the US, let alone other countries.  I/we probably should have been more clear.

skeptic - your post may have been, but the original poster specifically mentioned help on other country's standards as well.

skeptic

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Re: Straight answers about digital cable
« Reply #14 on: January 07, 2009, 03:44:48 pm »
Only converting channels 30-99 to digital?  May I ask where you got this?  It's different info than what I was told, and if I were told wrong then I need to re-evaluate my plans to go with HDHomeRun (no NTSC therefore no channels 2-29).

Does this hold true for their Digital packages as well or will their digital packages truly go all digital sometime next month?

I know this to be fact.  How I know this I'd rather not say publicly as I'm bound by certain rules regarding that subject.  The current plans as they exist are to migrate 30-99 to all digital format in the first half of 2009.  Timing is not specific as different markets are in different stages of upgrading plant and equipment, and it will take some time to get the necessary equipment into customer's hands.  2-30 which comprise the "limited" lineup which is mostly of the local SD broadcast stations and the public access channels will remain as analog content.   Currently all of the limited and basic channels 2-99 in most markets are simulcast in digital form (and have been for some time) and when received through a STB or QAM are received in that format. 
If you have inside info I have no need to know where/how, getting actual facts from Comcast as a customer is nearly impossible through normal means so you sharing is great. 

I have comcast in New England and I have a hd homerun....

From my experience I get the major stations NBC ABC ETC in clear quam .... CPTV and about 20-30 stations total.

Tim
I live in San Francisco, and get pretty much the same channel selection using my HDHomerun that Tim gets. The major stations, and local community channels.  I cannot tune the 30+ cable channels, even though I'm signed up with comcast's digital package.

shane

From the three posts here it sounds like sometime in the first half of '09 all Comcast customers should be able to use HDHomeRun to access every channel in the 2-99 range, although some channels may not map the same, ie 2-1 is digital 2 and I've seen weird stuff like 68-102 is some other random 2-99 channel...

For the QAM channels that don't match the comcast channel number, how hard is it to map these so the onscreen guide/schedules direct stuff works?