My computer came with a PCI TV tuner card from STB. The manufacturer provided drivers for Windows 98, but of course, shortly thereafter, the manufacturer disappeared from the face of the earth. Obtaining a suitable driver for Windows XP was nearly impossible until the recent development of open-source WDM drivers for all BT848-based tuner cards. However, although getting the card to work under Linux was a bit tricky, it was not at all impossible. This is a brief log of the steps I took to get the damn thing to work under RedHat 9.
At first I tried to use xawtv just to see if I could get a picture. And in fact, it actually showed Channel 3, which got me excited. However, there was no sound, and I couldn’t change the channel. I knew that the configuration of bttv was somehow wrong. After poring over the BTTV HOWTO document, I came up with the following lines to add to /etc/modules.conf:
# TV settings
alias char-major-81 bttv
pre-install bttv /sbin/modprobe -k tuner; /sbin/modprobe -k msp3400
options bttv radio=1 card=3
options tuner type=2
The parameters specified above correctly identify the STB TV PCI card, and even enable FM radio functionality, which the card supports.
After a reboot, xawtv worked wonderfully. However, there was soon a new problem: I installed an updated accelerated video driver from NVIDIA, which made xawtv crash with a segmentation fault. After searching the web for answers, I found the following solution: simply start xawtv with the command line xawtv -device /dev/video0. That’s it!
One more minor issue was getting the program called tvtime to work. This program is vastly superior to xawtv, but it had a slight problem where it automatically turned up the tuner volume all the way, and let the user control the volume through the mixer. This wasn’t good because the STB card clips the audio if it’s above 50% volume, so it sounded really distorted and rectified. All I needed to do to fix this was find the line of code where tvtime sets the tuner volume, and change the default number. The number that it was setting the volume to was 60000 (presumably the maximum is 65535). So I changed it to 32000 and recompiled. It now runs marvelously.
(Update 10-24-04: I submitted a bug report to tvtime, and the author added a preference to control the audio gain on the tuner card itself. Thanks!)