repo.pgp.key not found / Repository not working?

Hello guys,
I have a serious problem installing tvheadend. I can't get the pgp key, I always get a 404 when I try to download. Also the repository seems not working on http://apt.tvheadend.org/stable/ is always a page not found. Is the repository down, or what am I doing wrong? I followed the instructions on the downloadpage. I tried on Ubuntu and on rasperry. Please help.