[mythtv-users] Server/adding new card dilemma, HD/hardware questions

R. G. Newbury newbury at mandamus.org
Fri Oct 3 03:31:09 UTC 2008

Bobby Gill wrote:
> On Wed, Oct 1, 2008 at 2:49 PM, R. G. Newbury <newbury at mandamus.org> wrote:
>> Bobby Gill wrote:
>>>>> Well, yes.  But even now most analog is echoed on the SD multiplex.  In
>> my
>>>>> area, digital gets me what I need.  Maybe with cable it's different but
>> I
>>>>> would suspect that getting an analog tuner set up and running will only
>>>>> give you a few weeks of use at best.
>>>>> --Yan
>>>>> Pretty much same thing going on here. The only one that for me has
>>>> different programming on analog is the local PBS station.
>>>> Richard
>>> Okay, lost me here. Are you saying that if I get a card that captures
>>> Digital TV only (no analog input), and I just have regular analog cable
>> TV
>>> right now, I can capture it fine? ie., Digital is kind of "backwards
>>> compatible" to grab analog?? I think this area confuses me most lol.
>>> FYI I am using Rogers Cable TV (regular cable) in Canada. Family room has
>> a
>>> Rogers Digital box (that I don't use as part of Myth; frontend is desktop
>> PC
>>> in bedroom).
>>> Thanks
>>> Bob
>> You get Rogers Cable. That is analog. You also have, at least, some
>> digital capability. Think of these just like different radios: AM and
>> FM. Can't listen to AM on the FM radio and vice versa.
>> Digital is NOT backwards compatible with analog.
>> Rogers no longer even offers an analog basic package, so the writing is
>> on the wall, that it will (eventually) move all the analog channels to
>> digital streams only.
>> At the moment, you record off the cable with a PVR-150. It has on-board
>> hardware compression, and does only Standard Definition TV.
>> EVERYTHING which Rogers sends as a digital signal is encrypted. Rogers
>> used to transmit about 35 QAM encoded, unencrypted channels, but stopped
>>  that about June 2007. Now everything digital is encrypted, which means
>> you must use a set top box to unscramble the signal.
>> It is clear that Rogers wants to suck as much as possible from the
>> customer, and CONTROL the customer's capability to record, as much as
>> possible. And there are no 'must-carry' rules in Canada from the CRTC as
>> there are in the US from the FCC.
>> Your digital set-top-box, MAY have a firewire output (but I don't think
>> anyone has confirmed that wrt Rogers supplied boxes). If so, you can
>> record the digital stream using a firewire input on your mythbox. ( I am
>> fairly sure you can buy firewire capable STB's which work with Rogers.)
>> The only other choice at the moment, is the new Hauppauge HD1212 which
>> takes (analog) component video output from the set top box and encodes
>> to to digital, which you then record. The STB must have component
>> output. Only the most basic (cheapest) STB's do not have component.
>> HDMI generally does not work for output because it is crippled to only
>> talk to HDCP recognized devices, like your LCD TV but to never allow a
>> digital stream 'into the wild' so to speak. In other words, it is DRM
>> crippled. (I don't know of any TV's which will pass through an HDMI
>> sourced signal, and strip it. The only not-so-reasonably priced unit
>> which was advertised to strip HDCP from a HDMI/DVI signal was made in
>> Germany and is apparently no longer available: the Spatz DVIMagic box
>> amd it was listed at 400 euros.)
>> The next problem either way is that you need one set top box per channel
>> to be recorded: that is, one set top box, plus firewire/HD1212 input
>> (plus an IR blaster for channel changing) is equivalent to your PVR150
>> in terms of tuning the channel and recording a stream.
>> If you want more channel recording capability at present, you could add
>> another PVR150. That would be the cheapest route to add extra capability
>> for the foreseeable future. Best guess is that Rogers will not force a
>> changeover until Canada goes all-digital in August 2011 (although there
>> will probably be some changes in February 2009 when the US changes). So
>> you can get good use of a $60-75 purchase. If you do not have a spare
>> slot you could change to a PVR500 for 2 tuners, or add one of the
>> Hauppauge USB analaog tuners.
>> If you want to future proof yourself, then you have to think about the
>> digital route.
>> And HDHomeRun is a great little unit, but it only works with unencrypted
>> QAM cable signals, or OTA. I have one connected to my antenna (in
>> Mississauga, south of Lakeshore) and I get 23 channels ( ignoring SD
>> versions of HD feeds). So unless you are able to put up an antenna this
>> box is not for you. The antenna installed cost me less than $200 with
>> all parts, and coax cable, but I did the installation.
>> So far I have said nothing about HD. If you get HD channels on your STB,
>> then the same questions arise. You need firewire or another form of
>> output from the STB to feed your mythbox. Once you are digital the
>> definition level makes no real difference on the input side. The
>> differences are all on the output side, in terms of what your screen can
>> do, and your hardware provide. But what you have will be fine for
>> standard def for a couple of years.
>> Geoff
>> --
> Holy crap, you guys are amazing! Been reading the thread now and trying to
> let it all sink in. Lots of new info for me :)
> So now with the explanation of the Rogers digital box, I'm curious. Let's
> say I get another Rogers digital box (same as one already in family room).
> Now if I want to use it exclusively with Myth, I would what-- plug it in to
> my server? ie., Connect it to the PVR-150 and my PVR-150 now captures from
> the digital box?

Rogers STB's are, in a sense, locked boxes. The only output is usually 
an analog (VGA or Component or composite) signal, or a (locked) 
HDMI+HDCP digital signal. In the US, FCC rules require that you can get 
an STB with a firewire output. I do NOT know if you can demand the same 
from Rogers, but I think some of the better STB's offer that.

Presuming you have a firewire output, you would feed that to a firewire 
input on your mythbox. Myth has the capability. You would also need an 
IR blaster to 'talk' to the STB, to change channels at the correct time, 
for recording. All input through the firewire input must be 'pre-tuned' 
at the STB. The IR blaster is just a computer controlled remote.
You cannot connect a digital signal to a PVR150 and get anything useful.

The only other existing method for getting input from an STB to the 
mythbox, is the new Hauppauge HD1212 analog/digital box. It takes an 
analog signal in component form (3 cables) and creates a digital output. 
This box is new, and the drivers are still in beta. From what I read, it 
appears to work reasonably well already. But you STILL need an IR 
blaster to change channels on the STB. The HD1212 is future proof if you 
have an STB with component out. Most of the Rogers STB's have component, 
iirc from my last troll through the Rogers website.

> With the Rogers box having its built-in Guide and all that, how would that
> affect my desktop PC as frontend? Would I have to have the digital box
> plugged into my desktop PC as frontend? Or can I just use my mythfrontend as
> is?

The Rogers guide is irrelevant to myth. Your frontend would not know 
that it was there. The guide is just digital data sent on the cable to 
your STB, which is a computer, and formatted for display on a spare 

Everything discussed above about inputs etc. is into the myth backend 
box or a slave backend box. None of it affects your frontend(s) which 
can be anything which will handle the load, a laptop, and bigger box 
etc. All interaction between a frontend and the backend is actually done 
through the mysql database, except for the video stream.

I strongly suggest that you  spend some time at the mythtv wiki. There 
are articles covering all of the aspects discussed here.

And to satisfy my curiosity, does your STB have a firewire output socket 
on it? And if so, is that socket activated, so that you can use it?


BTW, where are you? ROgers covers a fair chunk of Canada.

> I am edging closer to another PVR-150 or 500 for now but just want to be
> sure and not waste $70-$80 if it makes more sense to spend a bit more and
> improve things.
> Thanks a TON!

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