Michaels blog

I have a MediaCenter PC running Ubuntu Linux and MythTv. It works very well, and until now my TV input has been through a Hauppauge PVR 500 card.

I just added a Hauppauge Nova-T DVB-T card since it is now possible to receive DVB-T signals in Denmark.

It was fairly easy to get working once I had a good enought antenna.

The driver, cx8800, is included in the Linux kernel. I’m currently using 2.6.17.3 which gives me working DVB-T, but broke ivtv and my PVR500 card….

When the driver was loaded i tested the signal with the scan and tzap applications from the dvb-utils package. On www.digi-tv.dk i found that there is one transponder near Copenhagen and that the frequency is 714000000 hz.

The dvb-utils package comes with definition files for a lot of countries, but not for Denmark. I created one myself containing:
# Denmark - Copenhagen
# T freq bw fec_hi fec_lo mod transmission-mode guard-interval hierarchy
T 714000000 8MHz 2/3 NONE QAM64 8k 1/4 NONE
I saved the file as dk-Copenhagen and used the scan tool to look for channels:
$scan dk-Copenhagen
scanning dk-Copenhagen
using '/dev/dvb/adapter0/frontend0' and '/dev/dvb/adapter0/demux0'
initial transponder 714000000 0 2 9 3 1 3 0
>>> tune to:
714000000:INVERSION_AUTO:BANDWIDTH_8_MHZ:FEC_2_3:FEC_AUTO:QAM_64:TRANSMISSION_MODE_8K:GUARD_INTERVAL_1_4:HIERARCHY_NONE
0x0000 0x0065: pmt_pid 0x0000 DigiTV -- DR1 (running)
0x0000 0x0066: pmt_pid 0x0000 DigiTV -- DR2 (running)
0x0000 0x0067: pmt_pid 0x0000 DigiTV -- Tegnsprogstolkning (running)
0x0000 0x00d9: pmt_pid 0x0000 DigiTV -- TV 2 (Lorry) (running)
Network Name 'Kbh. Vest'
dumping lists (4 services)
DR1:714000000:INVERSION_AUTO:BANDWIDTH_8_MHZ:FEC_2_3:FEC_2_3:QAM_64:TRANSMISSION_MODE_8K:GUARD_INTERVAL_1_4:HIERARCHY_NONE:111:121:101
DR2:714000000:INVERSION_AUTO:BANDWIDTH_8_MHZ:FEC_2_3:FEC_2_3:QAM_64:TRANSMISSION_MODE_8K:GUARD_INTERVAL_1_4:HIERARCHY_NONE:211:221:102
Tegnsprogstolkning:714000000:INVERSION_AUTO:BANDWIDTH_8_MHZ:FEC_2_3:FEC_2_3:QAM_64:TRANSMISSION_MODE_8K:GUARD_INTERVAL_1_4:HIERARCHY_NONE:311:0:103
TV 2
(Lorry):714000000:INVERSION_AUTO:BANDWIDTH_8_MHZ:FEC_2_3:FEC_2_3:QAM_64:TRANSMISSION_MODE_8K:GUARD_INTERVAL_1_4:HIERARCHY_NONE:2111:2121:217
Done.
Which tells me it’s working! The output (not the first line) must be saved in a file called $HOME/.tzap/channels.conf and then the signal quality can be checked using the tzap command. E.g.
$ tzap DR1
using '/dev/dvb/adapter0/frontend0' and '/dev/dvb/adapter0/demux0'
tuning to 714000000 Hz
video pid 0x006f, audio pid 0x0079
status 01 | signal 0030 | snr 8000 | ber 00003fff | unc 00000000 |
status 1f | signal 0031 | snr ffff | ber 00000000 | unc 00000000 | FE_HAS_LOCK
status 1f | signal 0031 | snr ffff | ber 00000000 | unc 00000000 | FE_HAS_LOCK
If you don’t get FE_HAS_LOCK you need to adjust the antenna. If you do get locked on to a signal however, you should be able to play an mpeg stream with
dvbstream -o -ps -qam 64 -cr 3_4 111 121 | mplayer -
where 111 and 121 are the video and audio pid found as third and second last values on the channels line in channels.conf

This entry was posted on Thursday, July 6th, 2006 at 11:37 and is filed under Media Center. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.