Besides doing a little testing of the Pi2 hardware and memory, I have been doing some research and trying to decide where to start.
I ordered the TBS 5922. The TBS 5980 has the same chipsets as the non-existant Prof 7500 apparently but the only place I can find one
is a low rated Amazon seller. Read the one review, pretty bad and funny!
So I figure on the Pi you will need a piece of software that talks to the tuner and presents a stream for the player.
I was playing around with some of the prepackaged media centers but wallyhts got me thinking
in a different direction. And I also have a wild idea of building an IP-LNBF of sorts at the same time
consisting of a tuner and PI out at the dish sans coax. The coax run distances alone in my house, nevermind the runs out to the dishes,
would make you cringe, its a wonder I get a signal at all!
I had a brainstorm on how to power the thing by simply using power over the coax that already runs out to the dish. Just like the powered multiswitches use. The Pi runs at 5V and the 5922 runs higher. I will run the higher voltage out to the dish and regulate it down to 5V for the PI.
Anyway I researched two interesting and similar pieces of software, Dvblast and Mumudvb.
Both are available through apt-get on the PI and source code.
Dvblast is multicast only, and to install as a service you must write all the necessary scripts
https://github.com/gfto/dvblast/blob/master/README
http://www.videolan.org/projects/dvblast.html
Mumudvb will do unicast http as well as multicast
The mumudvb package also installs the service scripts.
Install through apt-get do a couple of config files
then service mumudvb start
http://www.mumudvb.net/doc/mumudvb-1.7.3/README.html
http://www.mumudvb.net/
For my initial test, once my tuner arrives, I will be trying mumudvb in http unicast mode.
Example of 4 channel setup:
Channel 1
http://10.0.0.1:5001
Channel 2
http://10.0.0.1:5002
Channel 3
http://10.0.0.1:5003
Channel 4
http://10.0.0.1:5004
There are other options such as channel by number and channel by sid.
http://10.0.0.1:4242/bynumber/3
http://10.0.0.1:4242/bysid/100
It can also generate m3u playlists.
Initially the client will probably be VLC on a laptop.
You could also use one of the media centers and tie the url to a channel source I would think.
Once I get everything configured and working properly on the "tuner" PI,
I will take my second PI and build a STB. The STB will basically just use a player to make an http connection to the tuner and
simply go to the next url to change the channel. I will build everything on the bench first and will attempt
to run the tuner/STB player all on the same unit to check performance for those interested in building an all in one unit.