SD and HD?
No error message?
Have you tried checking all coax connections to make sure they are tight?
This is mainly a peer to peer support forum, so baring an idea for an issue, you wil need to connect support for assitance.
I am having the same problem. Fox News will show for a few minutes and then the screen turns black. No other channels are having the issue. Suggestions to fix?
See my questions above for troubleshooting.