How can I stop sleep mode after a couple hours?

What is the receiver model? You should be able to go to Menu, Settings, Power Saving, and turn it OFF. Then, the receiver won’t turn off after four hours of inactivity.

HR24-200. Turning off power saving does not fix this. I called DIRECTV and they confirmed that. I asked them about Dog Tv and they said that was a good point but the DIRECTV will go into sleep mode no matter what.

I think it is screen saver and not power saving that's the problem.

It’s not Dog tv, it’s your receiver. A receiver should not go into screen saver mode when watching live tv but these older HR receivers apparently do. I experience this on my old HR-22. It tends to do that when tuned to any channel for a long time without any input from the remote.

I don't want to go to Genie because I have too many receivers in the house and would have to break it into two or three separate families of receivers. I didn't think it was specifically Dog TV. I'm just saying that the point of that is to entertain your dog for hours and it makes no sense that it would go into screen saver ever.  So I guess nothing I can do unless I go to Genie?

The scren saver is unavoidable, even with Genie setups. Unfortunately DogTV does not override it. All you can do is turn off the power saving option, not the automatic screen saver.

Don't know what you mean by separate famlies of receivers. The regular Genie line (HR34, HR44, HR54) works with all HDDVRs (HR20 thru HR24, and special R22) and HD non-DVRs (H21 thru H25). Only the Genie-2 (HS17) forbids everything but Clients on the account.

Just teach your dog to hit a button on the remote every couple of hours and it won't go to sleep :)