DVBSky T680C

DVB-C and DVB-T/T2 capable USB box with CI from DVBSky. TechnoTrend TT-connect CT2-4650 CI is more or less the same device, so information on that page is applicable to T680C as well.

Open-source driver exists and is included since kernel 3.19.

Features

• USB 2.0 (Type B)
• 12V Power Supply
• Integrated IR receiver
• Belling Lee Connector (Cable or Antenna)
• Common Interace (CI) Slot

Driver Installation

• See DVBSky wiki page.

Identification

$ dmesg | grep -i dvb
[   12.930074] usb 1-4: dvb_usb_v2: found a 'DVBSky T680CI' in warm state
[   12.930113] usb 1-4: dvb_usb_v2: will pass the complete MPEG2 transport stream to the software demuxer
[   12.930123] DVB: registering new adapter (DVBSky T680CI)
[   12.930267] usbcore: registered new interface driver dvb_usb_dvbsky
[   13.008400] usb 1-4: DVB: registering adapter 0 frontend 0 (Sit2 DVB-T2/C)...
[   13.207713] Registered IR keymap rc-dvbsky
[   13.207799] input: DVBSky T680CI as /devices/pci0000:00/0000:00:12.2/usb1/1-4/rc/rc0/input11
[   13.207845] rc0: DVBSky T680CI as /devices/pci0000:00/0000:00:12.2/usb1/1-4/rc/rc0
[   13.207849] usb 1-4: dvb_usb_v2: schedule remote query interval to 300 msecs
[   13.207852] usb 1-4: dvb_usb_v2: 'DVBSky T680CI' successfully initialized and connected
[   19.444990] dvb_ca adapter 0: DVB CAM detected and initialised successfully

$ lsusb | grep -i Conexant
Bus 001 Device 003: ID 0572:680c Conexant Systems (Rockwell), Inc.

Test case - Hardware - Reception - Comparison

Used as DVB-C device connected to german cable provider Kabel BW (Unitymedia). Replaced a Technotrend TT-connect CT-3650 CI (hardware breakdown, seemed to die of overheating or something). Software used: Ubuntu 13.04 (amd64), TVHeadend and XBMC. PC is an Atom D525-based Zotac Z-Box ID-34 (NVidia ION).

Good reception and quick channel switches. Works very well. Scanning for channels in tvheadend didn't find all the channels at first scan, due to bad reception, however after manually mapping them they worked flawlessly.

Compared to CT-3650 CI: The T680C doesn't heat up (just under hand-warm), even after hours receiving HD-TV channels (720p). It has in general better reception than the CT-3650 and is able to recive all channels. CT-3650 had frequently problems on the same line and some of the channels could not be used without frequent bit errors. From my point of view the DVBSky T680C works much better and more reliable than the Technotrend CT-3650 CI.

Compared to my GRUNDIG Television (40 VLE 8221 BL): Signal quality of channels looks much better on the GRUNDIG by value, however the channels work exactly the same. The T680C shows less good signal value for some channels but is better able to decode them afterwards / less or none image scatter compared to the Grundig Televisions build-in DVB-C.

Seems to be good hardware.

MythTV =< 0.27

MythTV 0.27 does not specifically support hybrid DVB cards. It will only attempt to use the DVBSky T680C as a DVB-T card. As a workaround the driver download (from bst-14 on) contains a ```build_dvbc_x64.sh``` script that makes the driver only show it's DVB-C/Annex_A delivery system (".delsys").

Alternatively you could try to set the card to DVB-C before starting mythtv-backend with ```dvb-fe-tool -d DVBC/ANNEX_A -a 0```