If you use the Unitrunker just put in the control channel. Than take the radio and scan the other 3 freqs. Cause on Unitrunker doesn't put in the other 3 freqs you'll have to watch the radio and computer screen see what lcn is for the blank freq slot. That is how I got about 60 sites for slers.
Okay depending it can take a mint to a few hours depending how much they hang on that freq. When Control Channel is active it will put in the lcn quick. Did you remember what LCN was for that Control Channel you had? Forgot to mention the uniden doesn't show correct site(s). Unitrunker is the way to get a true Site Number vs Uniden. I have been asking Uniden to look into that since it gives false numbers.