Merlin may be using DSD and I have not taken that deep dive on how to use it but I am using unitrunker and finding all my Astro Band Plan aka IDEN info that way that I need here in the DC metro area. Needless to say I can monitor at least 25+ systems within a 10 mile radius 5 state systems,including Washington DC , plus 15 counties as well. I found that using Global settings works very well when creating a new codeplug. Using RPM14c05 here for both my xg100m with the CH100 color control head that will hold up to 12,500 channels or 10 systems up to 1250 each. The CH-721 will only hold up to 1250channels, and 2 xg100p radios.