If you go on to QV's Website and look for the webmaster His name I believe is James or Jim. Send him an email. He is the chief dispatcher at QV. He probably will know and he will answer you on these types of questions. I have asked them before.
Currently this is the only radio and frequency for public safety and it is owned and operated by TN. The old radio used different PL tones to key up the four (4) different low band frequencies but that is all gone now. This is the only frequency there. Hope this helps.