I have an additional UHF remote and programmed it to work the main television but it will not work through the walls when I am in the other bedroom where the television is. Do I have to get another small antenna to mount on the back of the receiver?

I have a Dish 625 reciever that controls 2 televisions. We recently put a television in the spare bedroom but didn't want to get another reciever. I split the main television line so that whatever we are watching on TV1 is showing on the newly hooked up TV. However, since the new TV is in the...