If you are putting in the frequencies manually, and the system you are programming - you didn't identify it - is not P25, you will need to add data to the tables manually. I'm assuming you are talking about the Smyrna Tenn. system you referenced earlier.
The article I quoted above has the correct information as to how to fill the tables out, as does the FreeScan article (mentioned earlier) which has the same information. It's just applied differently due to the way the authors present the form, that's all
You might want to check in the Tennessee forum and see if there's anything out of the ordinary about that system, but under normal circumstances, this should work 73 Mike
[edit] Here's the database listing for the Smyrna system;
Smyrna Public Safety Trunking System, Smyrna, Tennessee - Scanner Frequencies
Something is very wrong here. It looks like the rebanded frequencies were appended to the non-rebanded ones, and the non-rebanded ones are listed as a separate site. Very strange. As mentioned before, this might be a case where someone in Tenn. is a better guide. To me it looks like the DB entry is screwy.