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+Some very frequently asked questions about linuxtv-dvb
+
+1. The signal seems to die a few seconds after tuning.
+
+        It's not a bug, it's a feature. Because the frontends have
+        significant power requirements (and hence get very hot), they
+        are powered down if they are unused (i.e. if the frontend device
+        is closed). The dvb-core.o module paramter "dvb_shutdown_timeout"
+        allow you to change the timeout (default 5 seconds). Setting the
+        timeout to 0 disables the timeout feature.
+
+2. How can I watch TV?
+
+        The driver distribution includes some simple utilities which
+        are mainly intended for testing and to demonstrate how the
+        DVB API works.
+
+        Depending on whether you have a DVB-S, DVB-C or DVB-T card, use
+        apps/szap/szap, czap or tzap. You must supply a channel list
+        in ~/.[sct]zap/channels.conf. If you are lucky you can just copy
+        one of the supplied channel lists, or you can create a new one
+        by running apps/scan/scan. If you run scan on an unknown network
+        you might have to supply some start data in apps/scan/initial.h.
+
+        If you have a card with a built-in hardware MPEG-decoder the
+        drivers create a video4linux device (/dev/v4l/video0) which
+        you can use to watch TV with any v4l application. xawtv is known
+        to work. Note that you cannot change channels with xawtv, you
+        have to zap using [sct]zap. If you want a nice application for
+        TV watching and record/playback, have a look at VDR.
+
+        If your card does not have a hardware MPEG decoder you need
+        a software MPEG decoder. Mplayer or xine are known to work.
+        Newsflash: MythTV also has DVB support now.
+        Note: Only very recent versions of Mplayer and xine can decode.
+        MPEG2 transport streams (TS) directly. Then, run
+        '[sct]zap channelname -r' in one xterm, and keep it running,
+        and start 'mplayer - < /dev/dvb/adapter0/dvr0' or
+        'xine stdin://mpeg2 < /dev/dvb/adapter0/dvr0' in a second xterm.
+        That's all far from perfect, but it seems no one has written
+        a nice DVB application which includes a builtin software MPEG
+        decoder yet.
+
+        Newsflash: Newest xine directly supports DVB. Just copy your
+        channels.conf to ~/.xine and start 'xine dvb://', or select
+        the DVB button in the xine GUI. Channel switching works using the
+        numpad pgup/pgdown (NP9 / NP3) keys to scroll through the channel osd
+        menu and pressing numpad-enter to switch to the selected channel.
+
+        Note: Older versions of xine and mplayer understand MPEG program
+        streams (PS) only, and can be used in conjunction with the
+        ts2ps tool from the Metzler Brother's dvb-mpegtools package.
+
+3. Which other DVB applications exist?
+
+        http://www.cadsoft.de/people/kls/vdr/
+                Klaus Schmidinger's Video Disk Recorder
+
+        http://www.metzlerbros.org/dvb/
+                Metzler Bros. DVB development; alternate drivers and
+                DVB utilities, include dvb-mpegtools and tuxzap.
+
+        http://www.linuxstb.org/
+        http://sourceforge.net/projects/dvbtools/
+                Dave Chapman's dvbtools package, including
+                dvbstream and dvbtune
+
+        http://www.linuxdvb.tv/
+                Henning Holtschneider's site with many interesting
+                links and docs
+
+        http://www.dbox2.info/
+                LinuxDVB on the dBox2
+
+        http://www.tuxbox.org/
+        http://cvs.tuxbox.org/
+                the TuxBox CVS many interesting DVB applications and the dBox2
+                DVB source
+
+        http://sourceforge.net/projects/dvbsak/
+                DVB Swiss Army Knife library and utilities
+
+        http://www.nenie.org/misc/mpsys/
+                MPSYS: a MPEG2 system library and tools
+
+        http://mplayerhq.hu/
+                mplayer
+
+        http://xine.sourceforge.net/
+        http://xinehq.de/
+                xine
+
+        http://www.mythtv.org/
+                MythTV - analog TV PVR, but now with DVB support, too
+                (with software MPEG decode)
+
+        http://dvbsnoop.sourceforge.net/
+                DVB sniffer program to monitor, analyze, debug, dump
+                or view dvb/mpeg/dsm-cc/mhp stream information (TS,
+                PES, SECTION)
+
+4. Can't get a signal tuned correctly
+
+        If you are using a Technotrend/Hauppauge DVB-C card *without* analog
+        module, you might have to use module parameter adac=-1 (dvb-ttpci.o).
+
+5. The dvb_net device doesn't give me any packets at all
+
+        Run tcpdump on the dvb0_0 interface. This sets the interface
+        into promiscous mode so it accepts any packets from the PID
+        you have configured with the dvbnet utility. Check if there
+        are any packets with the IP addr and MAC addr you have
+        configured with ifconfig.
+
+        If tcpdump doesn't give you any output, check the statistics
+        which ifconfig outputs. (Note: If the MAC address is wrong,
+        dvb_net won't get any input; thus you have to run tcpdump
+        before checking the statistics.) If there are no packets at
+        all then maybe the PID is wrong. If there are error packets,
+        then either the PID is wrong or the stream does not conform to
+        the MPE standard (EN 301 192, http://www.etsi.org/). You can
+        use e.g. dvbsnoop for debugging.
+
+6. The dvb_net device doesn't give me any multicast packets
+
+        Check your routes if they include the multicast address range.
+        Additionally make sure that "source validation by reversed path
+        lookup" is disabled:
+          $ "echo 0 > /proc/sys/net/ipv4/conf/dvb0/rp_filter"
+
+7. What the hell are all those modules that need to be loaded?
+
+        For a dvb-ttpci av7110 based full-featured card the following
+        modules are loaded:
+
+        - videodev: Video4Linux core module. This is the base module that
+          gives you access to the "analog" tv picture of the av7110 mpeg2
+          decoder.
+
+        - v4l2-common: common functions for Video4Linux-2 drivers
+
+        - v4l1-compat: backward compatiblity layer for Video4Linux-1 legacy
+          applications
+
+        - dvb-core: DVB core module. This provides you with the
+          /dev/dvb/adapter entries
+
+        - saa7146: SAA7146 core driver. This is need to access any SAA7146
+          based card in your system.
+
+        - saa7146_vv: SAA7146 video and vbi functions. These are only needed
+          for full-featured cards.
+
+        - video-buf: capture helper module for the saa7146_vv driver. This
+          one is responsible to handle capture buffers.
+
+        - dvb-ttpci: The main driver for AV7110 based, full-featued
+          DVB-S/C/T cards
+
+eof