[mythtv-users] Summary of my HD experiences with MythTV 0.18.1
tngreene at pacbell.net
Mon Jul 11 15:41:40 EDT 2005
Over the last few weeks, I've been trying to put together a mythtv box
with an HD card (PCHDTV 3000), a Firewire connection to my Comcast
Motorola 6200, and a PVR-250 for regular TV. I had an earlier version
of Myth running great for about 1 year (non-HD), so I thought I'd give
the HD a try.
The project isn't finished (in fact, isn't working yet), but I thought
I'd share my experiences up to this point for those following in the
same path. Basically, all of the HD options I've tried so far haven't
been stable enough for using on a regular basis, though I'd appreciate
feedback from those having better luck with similar setups.
--> Graphics Card: As far as I can tell, only the NVidia cards do a
good job playing back HD without dropping frames. I purchased a fanless
GeForce 5200 card from NewEgg as recommended on Wendy's website:
--> Case: I got a Silverstone SST-LC11S, which I thought looked pretty
cool. I uses a riser board for mounting the AGP and 2 PCI cards
horizontally. The PVR-250 fits, but only barely after some wiggling due
to a strange screw near the end of the PVR-250.
--> Motherboard/Processor: I started with an AMD 3700+ and Foxconn
760GXK8MB-ERS (SIS chipset) motherboard. It was the only microATX
motherboard I could find with included firewire. WARNING: DON'T GET
THIS MOTHERBOARD!!! For some reason, (using Fedora Core 3 or Core 4),
the NVidia drivers hang the system immediately. Using the 64-bit
version of FC3 was a little better...it didn't hang the system, but I
couldn't get AGP enabled, so the frame rate wouldn't support HD.
So, I ended up buying another CPU/motherboard. this time a P4/3.0Ghz and
a Foxconn 865G 865G7MC-ES (once again, the only mobo I could find that
had built-in firewire and was a microATX, this one has an Intel chipset,
not SIS). This seems to work ok so far with the NVidia chip.
OS AND SOFTWARE
--> OS: I've stuck with FC3 so far (kernel 220.127.116.11), following Jarod's
great site at: http://wilsonet.com/mythtv/ However, I've been thinking
of trying KnoppMyth as well. .
--> Myth version 0.18.1 from atprms.net (thanks, Axel!)
HD CAPTURE --> Firewire
As far as I can tell, the Firewire connection to the DCT6200 is not
ready for prime time. This may be due to the firewire implementation
within the DCT6200, but either way, it works only intermittently. Here
are a few tricks to get it to work a little better:
Run "plugreport" to see which port and node the DCT6200 is connected
to. Then, repeatedly run "test-mpeg2 -r [node #]" and press ctrl-c
until you get an mpeg stream. You may need to repeat this step many
times, but at some point, you kick the DCT6200 into action, and the
connection then seems to work in Myth.
Also, I'd avoid watching live TV with the firewire connection, because
changing channels frequently causes a hang. Other times, the new
channel is either missing audio, or comes in at 3-4 frames per second.
If I quit the "live tv" function and re-enter, the audio re-appears and
the frame rate goes back to normal.
HD CAPTURE ---> PCHDTV HD-3000
I've tried the DVB drivers trying to capture QAM (QAM is the HDTV signal
sent over cable, vs. the broadcast HDTV, which is a different format).
This works, but just barely. The "scan for channels" feature picks up
most (but not all) of the HD channels coming over the cable. When
watching the channels, many of them have slower frame rates, the image
breaks up every few seconds, and changing channels when watching live TV
frequently causes a hang of the mythfrontend. Once again, not really
ready for prime time. I'm going to try the HD-3000 with terrestrial
signals next, and I'm hoping it will be more stable (though I don't get
as many channels over the air).
NTSC CAPTURE --> PVR-250
I thought this would be the easy one, since I had it working with a
previous myth box. However, either the card has gone bad, or the
Silverstone case has a lot of RF interference, because every channel
flickers uncontrollably (like someone is wiggling an antenna). It
crashes myth playback within 10 seconds. I've replaced the card with an
older K-World BTT878 that I got off eBay for $20 (which works), but I
would prefer the built-in MPEG2 compression of the PVR-250. I don't get
the static with the K-World card, so the PVR-250 card is looking more
Hopefully this posting will help folks trying to build an HD setup....
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