Archived:KWorld ATSC 110-V4L

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Features

Name V4L2 Support
Analog TV Yes
Analog Input selection Yes
TV, composite, S-Video
ATSC/Digital TV Yes
Sound Yes
Alsa direct only works with mplayer, using a pure digital path.
All programs work with supplied loopback cable; ATSC-100 audio out to sound card in.
Alternatively, several processes can accomplish a digital path. See ALSA audio.
Remote Yes
Requires patch
Not 100%, misses key presses.
FM Stereo No

As of August 2007.

Overview

Kworld-atsc-110.jpg

Note: Much of this information was taken from the mythtv wiki. I decided to put it here because many people have had questions and/or problems with this card. Since it uses video4linux, I felt that a copy of it should belong here.

The Kworld ATSC 110 has an nxt2004 chip like the ATI HDTV Wonder and AVerTV HD A180.

For analog sources it has no MPEG2 encoder, so Analog channels are encoded by your CPU. For digital sources, the card does no encoding or decoding as Digital TV streams are already MPEG2 encoded. This requires almost no CPU processing as data is streamed directly off the card.

There has been a lot of confusion over this card and whether this works or that works. Hopefully this will clear things up and make everybody happy.

Works with...

  • Cable
    • Digital
      • QAM-256 (Rogers Digital Cable and Wide Open West)
    • Analog
      • This would mean the same channels as a "cable-ready" tv would get.
  • OTA (Over the Air)
    • Digital
      • 8VSB Digital TV (standard and high-definition)
    • Analog
      • Standard analog TV
  • Analog Baseband Sources
    • Composite
    • S-Video
    • Audio

Remote

  • A patch for remote support is floating around on the v4l mail list, however it is not yet complete and stable.

Notes

  • On the card, there has always been this confusion on what input to use. There are two for coax on the back. Some people have had luck with the digital antenna input is on the bottom and the analog one is on top. I just purchased the card a week ago, and for me, the input on the bottom (closest to the PCI connector) is for digital cable (unencrypted QAM-256, that is), and the input on the top is for analog cable ("cable-ready" channels) as well as ATSC OTA. For others, it's the opposite.

TUV1236D Frontend

The TUV1236D frontend is completely enclosed. It contains the nxt2004 signal decoder and a TDA9887 IF PLL. The modules features include:

  • NTSC, ATSC and 64/256QAM reception
  • Low power dissipation (<1.75W)
  • Full frequency range coverage from 57MHz to 864MHz
  • SmartAntenna technology supported for enhanced ATSC reception
  • Sensitivity ~ -80 dBm

Over the air (OTA) reception

Using the -80 dBm figure, you can calculate theoretical values for receiving stations. For instance, Remote central has figures for station broadcast powers. The relevant formulas and data are:

  • Transmitter signal, Ts = 60 + 10*log(kw).
  • Distance loss, Dl = 92.4 + 20*log(km) + 20*log(gHz))
  • Antenna gain, ?.
  • Pre-amplifier gain, ?
  • Cable loss, 22dB/100m.
  • Connector loss, .5dBm.
  • Splitter, combiner losses, ?.
  • Receiver sensitivity, -80dBm.

The directionality and height of the transmit and receive antennas, multi-path signals, terrain and environment effect will all alter OTA reception. For instance a nearby building can reflect a signal, causing two mismatched signals to arrive and interfere. A directional antenna can help to prevent this, but you may then need a rotor to point the antenna at different stations. Rain, fog, hills, trees and interfering signals from electronics can all hinder reception. Ambient temperature also adds noise to the signal. The higher your margin the better the your experience will be.

Kworld ATSC 110 Setup

Directions for kernels 2.6.15 and newer

Note: For Ubuntu, the driver for this card is NOT included in kernels older than 2.6.17. If you have one, you probably have to download the cvs version of v4l and work some magic. I took the easy way out and just upgraded to Ubuntu 6.10, which includes the 2.6.17 kernel. This kernel already has the driver built-into it. You can tell if it works or not by running...

dmesg | grep -i saa7133

and look for

saa7133[0]: subsystem: 17de:7350, board: Kworld ATSC110 [card=90,autodetected]

If it says board: unknown, or anything other than Kworld, then it probably isn't being loaded by the kernel.

1. Download the firmware

# cd /[kernel source directory]/Documentation/dvb/
# perl get_dvb_firmware nxt2004

2. Place a copy of the firmware file (dvb-fe-nxt2004.fw) in your /lib/firmware directory.

3. Edit your /etc/modules file and insert an 'saa7134-dvb' right after the saa7134 entry that should already exist in the file. This will cause the module to load during boot.

4. Load the module

# modprobe saa7134-dvb

5. To get sound from the NTSC tuner via the PCI bus (i.e. without a loopback cable) you need to load one more module. This is not necessary for ATSC/QAM. Use 'index=1' if you only have one sound card. If you open 'alsamixer -c 0' or 'alsamixer -c 1', you should see what sound card is what in the upper left hand corner of the screen. saa7134 is the alsa one, your internal card is the other. Make sure your internal card is '0' or else you could have sound issues.

# modprobe saa7134-alsa index=1

This should also be added to your modules file so it will load during boot.

6. You may need to run extra commands on boot to unmute the analog card. v4lctl is required; install xawtv to get it.

# v4lctl -c /dev/video0 setattr automute off
# v4lctl -c /dev/video0 volume mute off

This assumes that /dev/video0 points to the Kworld's device. I put these commands in a script, which is run when the MythTV backend starts up.

Directions for kernels prior to 2.6.15

1. Go to http://linuxtv.org/hg/v4l-dvb?cmd=manifest;manifest=b6adae07b19677a78c029cdb64007ba81b17fe4a;path=/;style=gitweb and download the newest version of Video 4 Linux by clicking on the bz2 link near the top.

2. drop the file into your /usr/src directory.

3. unzip the file by typing "tar xjvf [filename]" in to the command line.

4. Enter the directory the source was unzipped to do a make and make install.

$ cd /usr/src/[unzip directory]
$ make
# make install

5. Now you need to get the firmware. You can do this by running the /usr/src/[unzip directory]/linux/Documentation/dvb/get_dvb_firmware.

# cd /[unzip directory]/linux/Documentations/dvb/
# perl get_dvb_firmware nxt2004

6. Place a copy of the firmware file (dvb-fe-nxt2004.fw) in your /lib/firmware directory.

7. Lastly, edit your /etc/modules file and insert an 'saa7134-dvb' right after the saa7134 entry that should already exist in the file.

8. Load the module

# modprobe saa7134-dvb

This is a cleaned up version the the instuction found at [http://mysettopbox.tv/phpBB2/viewtopic.php?t=8695