If you add a fake system ID to the NETWORKS file, then the SITES, then the Frequencies files, it will key on the frequency and create a Groups and Radios file with that fake SYSID. You can then edit the aliases
So my entry for Springfield MA FD, I used the area code (use whatever you want 1 to 4095) Made for Tier III but it works for me on P25.
Network:
P25, 413, "Springfield FD P25"
Site:
P25, 413, 1, "Springfield FD P25"
Frequencies:
P25, 413, 0, 1, 154.1750, 0.0, 0 ; Springfield FD
P25, 413, 0, 1, 154.4000, 0.0, 0 ; Springfield FD
It produced a single group. I chose not to name it as there is only one used:
P25, 413, 1, 50, Normal, 12225, 2025/08/18 11:33, ""
Radios:
P25, 413, 1, 1, 50, Normal, 4102, 2025/08/18 11:33, "Dispatcher"
P25, 413, 1, 2, 50, Normal, 3981, 2025/08/18 10:52, "Dispatcher"
P25, 413, 1, 146, 50, Normal, 93, 2025/08/09 0:02, "Car 1-P (1) (Commissioner)"
P25, 413, 1, 148, 50, Normal, 31, 2025/08/09 0:49, "Car 1-P (2) (Commissioner)"
P25, 413, 1, 149, 50, Normal, 40, 2025/08/09 9:27, "Chief 1-P (1) (Deputy Chief)"
P25, 413, 1, 150, 50, Normal, 146, 2025/08/16 23:49, "Chief 2-P (2) (Deputy Chief)"
Etc, for 150 or so radios.
Sometimes it does not take but usually <left arrow> <right arrow> in FMP to move it off the channel and back on causes it to grab the custom entries. Scanning the 2 frequencies sometimes causes a hiccup as well but it is not a big deal.
chris