Newbie question here. I am wonder if I can put two different sources, ie Comcast internet and DirectTV onto one single coax, then at the destination, split the coax and feed the one to cable modem and the other to DirectTV dvr?

Is this possible?

Dish network installers frequently combine OTA with satellite signals on one coax using diplexers. This option can be used on Directv but is not supported by D*. It is not possible to mix cable and satellite signals on the same coax.

Dish network installers frequently combine OTA with satellite signals on one coax using diplexers. This option can be used on Directv but is not supported by D*. It is not possible to mix cable and satellite signals on the same coax.

what about Comcast internet with DirectTV?

Don't - IF you have internet problems - that's what they will point at first.

what about Comcast internet with DirectTV?

My understanding is you cannot diplex D* and cable (internet or tv) into the same coax and split back out at the tv.