Since this remote does not have an entry for Pluto brand televisions, you can use the "Standard Step-and-Set Programming" method to methodologically test different sets to see if a generic setting will work for the television.
If one is not found using that method, then the remote is likely not compatible with that television.
Answers & Comments
The codes for televisions are found in the manual of the remote:
http://www.scribd.com/doc/65386721/Jensen-JR300-JR400-JR500-Manual
Since this remote does not have an entry for Pluto brand televisions, you can use the "Standard Step-and-Set Programming" method to methodologically test different sets to see if a generic setting will work for the television.
If one is not found using that method, then the remote is likely not compatible with that television.