| I have the same Dish receiver.
The main TV is wired to TV1, but it first hits my VCR/DVD recorder using the S-video and RCA audio outputs.
The house cable wiring (with three TVs total) is connected to TV2's RF output. That output doesn't put out a lot of power -- only +3dB as I recall. I installed an 11dB inline amplifier bewteen TV2's RF output and a splitter in reverse (combiner) with the other tap connected to my roof antenna.
An added benefit of this hookup is that I can record one Dish program while watching another by changing the main TV from the AV input to the Antenna input -- in my case, on channel 53 -- and using TV2's remote.
As Fred said, the lower the channel the better because RG cable attenuates higher frequencies more than lower frequencies. If you're combining an antenna as I am you'll have to choose a channel for TV2 that has at least one channel open above and below so it doesn't interfere. In other words, if there are local stations on 22 and 26, choose 24. That's why I had to use channel 53: Living on the US/Canadian border makes the OTA TV band quite crowded.
Dish is pretty popular in my area and as you know, TV2's remote is a UHF. When I first got the system my neighbor and I were changing channels on each other's TVs. I switched the remote to another UHF channel and all is well.
Lastly, don't split the signals at each TV. Rather, use a single splitter after the amp if you can to feed all the TVs. The reason is, each two-way splitter will drop the signal by 3dB. The effect is additive: Two splitters = -6dB. Three = -9dB, etc. Better to use one three-way splitter in your situation since the loss would be -5.5dB.  |