Listen to EMSA OKC again...sorta

I've been noticing OKC FD telling responding units to respond to calls on "the EMSA channel" lately...but no traffic was ever seen on the database TG556 (analog or digital - used UniTrunker). I did see a new talkgroup on the city system - TG558 - and it was "just" digital...no encryption. Running DSDplus, and WHOA - you can hear EMSA again!!! OKC EDACS TG558 is linked to OKWIN TG 12912. I guess the guys in charge of that stuff figure ProVoice is almost like encryption (but it's not).