You cannot split the signal between the satellite dish and the 811. So you have to distribute the signal after it leaves the 811.
The 811 does not have an RF output for some reason, so the output from the receiver will have to be modulated and converted to an RF signal that can be sent via coax to your other TV sets. You can buy a modulator for less than $30 (here's one at Parts Express):
You'll also need a splitter to distribute the signal after it leaves the modulator.
One caveat: I've never used this modulator, and it's possible the signal that it produces is pretty weak, maybe not even useable with splitters to 3 TV sets over a long run. You might have to buy an inexpensive ($20) RF amplifier to install ahead of the splitter.