It sounds ike you have the original firmware on it.
Images are like software operating systems, the original version comes from vuplus.com, and you can go there and get the latest version, but other images, from dedicated enthusiasts, are available, like Black Hole, which you can get from this forum.
The satellites are in a list, in the software, the satellites.xml file, which can be found in the etc folder, tuxbox sub folder.
Using FileZilla, or other FTP program, copy the satellites.xml file to your computer desktop, open this with microsoft office excel, or other excel software, and you can view all the satellites in your list. Alternatively you can replace your old satellites.xml file with a new one containing 27.5W.