I have heard a new talkgroup in Duluth which pops up as "37700". It is obivisouly an encrypted group(I don't think it is the radio techs.) Just wondering who it is?
Did you try comparing the TG # with the other TG's surrounding that ID... that should give you some idea as to who it belongs to depending on how the system was configured.
It is wedged between St. Louis Co Talkgroups, and 787000-787100 seem to be reserved for radio sys techs. Perhaps it is StL Co Sys Techs as I assume they will need one or 30 sys techs to take care of that county and its 4500 radios...