MythTV + DirecTV..anyone?

April 14, 2006 3:15 PM

I would like to build a MythTV system to work with DirecTV. My questions are around the interface to the DTV receivers. Has anyone here done this? (Questions inside)

1) I want to record at least two things at once so I assume that means two receivers. Which receivers work best for this? I'd like them to be controlled (channel changes) serially and not to use any sort of IR blaster.

2) With two receivers, I assume you need two satellite access cards from DTV. This just means paying for a receiver in 'an extra room' I'm guessing?

3) Processor requirements for recording two things at a time and watching a third thing?

4) Best video out to display on a 50" plasma with component in?

Thanks!

spifl

posted by spifl to technology (8 comments total)

#1: no idea. there are 2 options, one is this serial protocol for control (S-link?) and the other is IR. no idea about the serial one, and infrared is hard since lirc is really a big PITA.

#2: yes

#3: recording processor requirements arent that high; i assume here that the mpeg2 encoding is done in hardware on the video capture boards. my athlonXP 3000+ can just barely keep up with 1080i (most of the CPU is spent on deinterlacing the video)

#4: ? for component video i've used an nvidia card with VGA output and the Audio Authority 9A60 with success.
posted by joeblough at 4:46 PM on April 14, 2006

Answer to question #2: yes, an extra room receiver charge.

Everything else, I got nothing.
posted by davejay at 4:47 PM on April 14, 2006

oh yeah - i should mention that i use mythtv strictly for OTA digital television, and have left my D* needs to 3 directivos (2 SD + 1 HD). so my answers are not based on experience.

the directivo is a great box. unforuntately D* has terminated their relationship with tivo, and when D* really gets going with mpeg4, you will be missing out on all that. hopefully though D* will have to keep their mpeg2 streams going for a few more years at least. after that, i'll have to move to comcast since that's who tivo has partnered with (though they will have cablecard-compatible "series3" boxen any day now which theoretically should work with any cable provider.
posted by joeblough at 4:52 PM on April 14, 2006

Huh, I had no idea:

DirecTV, TiVo Extend Partnership Through 2010

http://www.mediabuyerplanner.com/2006/04/12/directv_tivo_extend_partnership/index.php


I have 2 Directivo's, a Phillips 7000 and 8000, and have never needed more.
posted by thilmony at 5:17 PM on April 14, 2006

thilmony: wow. obviously that's pretty fresh news. it confirms what most people know, that the homegrown directv DVR is a complete POS. that's not surprising though, since everything except tivos are complete POSs.

but as your link shows, they are just going to keep guys like us going; no new subs. that's good. it also sounds like tivo is going take over maintenance of the boxes, which might mean we might get a frikkin' software upgrade once in a while (as opposed to never, except for bug fixes, since D* took over maintenance)
posted by joeblough at 7:37 PM on April 14, 2006

A few things I learned in researching a MythTV box:

1. You want a cable box with a FireWire port. This will let you skip an encoding/decoding step, and will cut down on the system requirements.

2. I recall someone saying that their P4 2800 could encode two streams while watching a recording. I don't know if that's the least you need to do it.

3. You want a tuner card with hardware encoding, such as the WinTV PVR-250 or PVR-350.

4. MythTV is kinda lousy to set up, and requires a lot of troubleshooting and frequent maintenance when it crashes for no obvious reason. I don't know your Linux skill level (mine's 'wimp') but I was told you really need to know what you're doing.
posted by Hildago at 9:40 PM on April 14, 2006

hidalgo #1: you will probably need to have your computer emulate a DVHS deck to get the firewire port to work. apple has a sample program for OSX that does this, and it does work. not sure if the same is available under linux. i cant remember - someone may have been working on this for use with myth. for realtime recording firewire would be a nice alternative to a capture card, but for archiving shows it kind of sucks, because most if not all STBs will only stream video out of the firewire port at real time, though the firewire port is probably capable of 10-20x realtime for a full-blown ATSC 1080i stream.

hidalgo #2: as you say in #3, if you have a card that does mpeg2 encoding, the load represented by recording a stream is pretty negligible.

hidalgo #4: yes, but things have gotten a lot better with KnoppMyth, in terms of installation anyway. still, it requires pretty constant hand-holding, compared with something like a tivo.
posted by joeblough at 12:00 AM on April 15, 2006

unforuntately D* has terminated their relationship with tivo

Good news. April 12th: TiVo and DIRECTV Agree to Extend Relationship for Three Years
posted by mrbill at 11:25 AM on April 15, 2006