Just for the record, the SDS scanners are SDRs. Any modern radio that has a firmware OS is a SDR. In fact, if I was to guess, I would suggest that the SDS model designation stands for software defined scanner. Although not currently available, the BlueTail scanners are specifically designed for simulcast systems, and work well in that environment. I think most people associate SDRs as a dongle that plugs into a computer. But the Uniden, Whistler, BlueTail, etc. have the computer contained within
B.S.