The Wentronic distributor has solved my problems completely reliable and also inexpensive.
At Master output now depends on the recording device - on the other slave. If the master device, I can look at the slave everything as I want. Then turns on the master device (eg for recording), so I can receive only programs of the same level on the slave. By Umschaltversuche on the slave to the master device (my recording so) can not influence. The scheduler works so perfect.
The signal quality is only slightly worse than without distributor - no comparison with the T-piece.
Thus, the switching to the slave device (if the master is not on) works fine, but the master device may invest no LNB voltage. In my case (I use the software DVB Viewer) can be turned off in the settings of these power DVB-S card inactivity.
This perfect feature for little money definitely deserves 5 stars!