[mythtv-users] interfacing MythTV with a DTA, lirc queries

[James Miller]

On Thu, 21 Jul 2016, John Morris wrote:

> I am going through this same process with SuddenLink.  You are correct,
> the OUT port has a standard def analog signal for whatever channel you
> are tuned to and you might also have an HDMI port which would give you
> a better picture on a TV but would almost certainly be locked with
> HDCP, at least when tuned to any interesting channel, making it not
> just illegal (I don't care about staying legal anymore) but difficult
> (I do care about that part) to use with Myth.
> Basically, you can still watch and record in SD.

Interesting. So should I be connecting what Gary said about analog NTSC 
with what you say about viewable/recordable SD, and assuming that the "to 
tv" coaxial jack on the back of these units outputs analog NTSC? Seems 
like maybe that is the case. If so, the problem then becomes how to do 
scheduling of recordings.

lirc can trigger DTA power on/off and channel changing for a MythTV 
system, from what I'm gathering. I know from a non-MythTV script I found 
and experimented with that an A/V stream from my NTSC capture device can 
just be dumped to hard disk (the script I tried used mencoder for this). 
But how to integrate something like this with MythTV's mode of operation? 
Would it be a matter of using lirc as "external channel change command" 
(mythtv-setup > input connections)? Could I then set my capture device to 
always start on, say channel 3, the channel the "to tv" coaxial jack is 
set to output on? I might well be able to manage configuring something 
like that. Makes for a system with too many "moving parts" and thus 
additional points of failure, but it seems as though it could be made to 
work. Are any other Myth users else doing this sort of thing?

And a final question regarding this viewable/recordable SD output, which I 
presume to be analog NTSC: how long is this sort of output expected to be 
available? I suppose the DTA is here performing the task of converting the 
digital signal to analog, and its hardware capabilities will not 
change--unless I may be required, for whatever reason, to swap it out for 
something else in the future. But the signal the cable co. sends out could 
change and perhaps become less congenial for conversion to SD/analog, 
could it not? Just wondering, should I try and set up my system along the 
lines described, how long I might expect the new configuration to last.

Yes, this DTA does have HDMI out. I mentioned it because some of the 
descriptions that I've run across so far for dealing with the new cable 
broadcasting conventions have focused on getting a stream from that output.

I'm still waiting to
> see how many channels my Prime gets after next week's conversion to all 
> digital and the Clear QAM hole closes.  Figure on losing the SD copies 
> of USA, SyFy, CNBC, MSNBC at a minimum, to go with losing the HD 
> copiesof those plus a couple more a couple years back.  Will very likely 
> lose more.  So I got the free box and am examining my options.  I have 
> an old PVR-350 I could reinstall to capture video from.

Not sure I follow this. Your Prime currently gets those channels in SD, 
with no DTA/STB in play? I do have access to such a device and was looking 
into possibly using it, but my cable company would not provide me with an 
m-card/cable card in place of the DTA, even though the DTA has a higher 
monthly rental fee. Anyway, I for one would be interested to know whether 
you will be able to get any further use out of that device, once your 
area's transition to digital/encrypted will be complete.