Well ya can… sort of. But ya shouldn’t.
The DIRECTV H25 Receiver is a marvelous thing. A sight to behold. So much raw HD power, so little size, and so little electricity used. But, even at that it’s not perfect. In order to get the size and cost down, some things had to go. Probably the most important is that the H25 won’t work if you hook it to a non-SWM dish. SWM technology takes a completely different set of tuners and chips than those used for the legacy dish, and DIRECTV just left out the old-school chips when they built the H25. It’s a good move, because all new installations use the SWM multiswitch, but it can be frustrating if you’re not ready to make the upgrade.
Because the H25 doesn’t have that extra tuner in it, because it isn’t designed to work with a legacy dish, it also doesn’t supply power to the dish over the coax line, and that’s another reason it won’t work.
If you hook a non-SWM dish straight to an H25, it just doesn’t work. There’s no muss, no fuss, you just won’t get a signal. It will be like the receiver isn’t hooked up to anything.
What to do then if you have an H25 and you want to use a round dish because it’s easier to aim? Obviously you know you won’t get HD service but if you want to go that way you will need a SWM Multiswitch to connect to that dish, or else the system won’t work. We’ve written a handy tutorial to help you connect the round dish to a SWM.