Tvheadend

tvheadend supports multiple dvb cards, and can support cards with twin tuners if they can be independently used under linux. This means that each tuner has it's own /dev/adapterX entry and that the use of one tuner does not limit the function of the other tuner.

Already with one dvb-t adapter can tvheadend record more then one program at a time. The only limitation is that both programs must be on the same transponder. With 2 adapters you can record multiple programs from 2 transponders etc. So if one transponder has 4 tv stations on it, you can record 4 programs from all 4 stations at the same time.

There is no need to define which device tvheadend will use when you schedule a recording. If you have 2 dvb adapters that both can receive the same program, then tvheadend will determine itself which adapter it will use based on the availability.

The only limitations are the available CPU power if you need to decode, (USB) bandwidth to the device and how quickly your HDD can save the streams. But on modern hardware you never hit these limitations unless you try to record a hugh amount of programs at the same time. I have done tests with 3 cards and 15 programs on a simple amd 3800+ cpu using 250Gb IDE HDD without much problems.

Hein

Hi,

thanks a lot for the fast and detailed explanation.
This sounds great.
Since i'm far away from beeing a SAT/DVB/TRansponder expert ;-) : How can i find out if some programs are on the same transponder? Or which programs are on the same transponder?
Or is this something i don't have to know when using tvheadend?
Will TVHE take care which adapter to use based on my scheduled records?
Is it ok, when i only select programs form the EPG and TVHE will do the rest or will tell me, that this is not possibel because the programs i want to record are on diferent transponders??

Any recommendations for a card?

Bet regards and a nice weekend

spline

if you go to the dvb configuration screen you see that there are 3 tabs in that screen: General, Multiplexes and Services.
If you go the service tab you can see all the services that that adapter can receive. You will also see a multiplex identifier in that list. If you sort by that you can see which services are together on the same multiplex. This information is kept up to date by the information that is send out via the dvb network. Tvheadend only needs to know a single multiplex and then, in a correctly configured dvb network, it can determine all other transponder locations and services based on the information it receives via the dvb-si information in the datasteam.

When you schedule a recording from the EPG tvheadend does not check if there are conflicts. Only when the recording is starting will tvheadend check if there is an adapter available to record the program. If there is no available adapter it will not record the show and log this the logfile. So that is why you might need to check if it is likely that tvheadend can record the program you scheduled.

To give you some idea, the DVB-T network here in the Netherlands consists of 5 transponders via which more than 20 tv stations are broadcasted. So if I would like to record ALL programs from ALL stations I only need 5 dvb-t adapters to do so.

Hein

and for a card suggestion.... any dvb card that is properly supported under linux can be used.
Have a look at the linuxtv.org dvb wiki for supported hardware.

Keep in mind that tvheadend does not support hardware based CI/CAM to watch encrypted channels. For that you need to setup a cardserver (like OScam) with a cardreader for your networks smartcard.

Hein