[mythtv-users] Probably a FAQ Question (HD, MythTV, Cable Card, and Comcast)

Rod Smith mythtv at rodsbooks.com
Wed Apr 11 01:49:56 UTC 2007

On Tuesday 10 April 2007 20:40, David Frascone wrote:
> Two last (I hope) questions:
> 1) What is the most popular tuner for analog & digital?  (Popular for
> price / performance, features, and reliability)

By "analog & digital," do you mean a tuner that will do both? If so, probably 
the pcHDTV cards. The latest model is the 5500. I must caution, however, that 
I own a couple of pcHDTV 3000 cards, and my opinion of them is very low, 
particularly for digital cable (QAM) reception -- they seem to work OK for 
some people, but they've got signal lock problems for others, apparently 
because of (very common) compatibility problems with random pieces or 
combinations of hardware. I don't know if the 5500 improves matters. Also, 
most (perhaps all) cards that do both digital and analog use framegrabber 
analog tuners, which means that the CPU must encode the video into the 
desired format (MPEG-4 or RTJpeg for MythTV). This increases CPU load, which 
can be a problem if your CPU is marginal (3GHz and below is "marginal" for an 
HD setup) and you want to record multiple channels or record analog while 
playing back HD content. HD recording is actually light on the CPU, since the 
card just sends a precompressed digital signal down the bus, which imposes 
very little CPU load.

For digital-only, the HDHomerun and AVerMedia AVerTVHD A180 both seem to be 
reasonably popular, but there are others, too. I replaced one of my pcHDTV 
cards with an A180 and it's like night and day; the A180 produces clean video 
with just an occasional minor digital "blip," whereas the pcHDTV 3000 
produces recordings that are literally unwatchable; they're missing so much 
data that MythTV usually reports them as half or less the show's length.

For analog-only, the Hauppauge product line, and particularly the 
PVR-150/250/350/500, seems popular. These cards support MPEG-2 hardware 
encoding, which greatly reduces CPU load. Other hardware-encoding cards 
exist, but they seem less popular. I happen to have an AVerMedia AVerTV 
M150-D, which is a bit finicky but can be made to work reasonably well 
(although perhaps not for channel surfing). I've also got a Hauppauge 
PVR-USB2, which is a USB-interfaced MPEG-2 encoder card that works reasonably 
well, except that it doesn't respond to MythTV's bitrate-setting commands, so 
all recordings have the same bitrate.

Check the wiki for information on quite a few video capture cards:


> 2) In regard to firewire -- how does that work?  Does it just constantly
> transmit what's playing?  So mythTV would change channels on the STB,
> and then store the stream to disk?  If so, shouldn't I do this before
> even buying a tuner card?

If you've got an STB with a Firewire port, it's certainly worth trying this 
approach before buying a separate card. AFAIK, there's nothing preventing you 
from using both an STB/Firewire setup and separate digital and/or analog 
tuners, so you can add to or replace your STB/Firewire configuration if you 

I've never actually used a Firewire input for MythTV, so I can't give you much 
in the way of details about how it works.

Rod Smith

More information about the mythtv-users mailing list