Always wondered about this if thier was a difference, instead of plugging in control channels and alternates to listen to whichever system, as for the talkgroup id's is it good to put them in, or just let it scan and find them? I guess my question is Is thier a difference between the 2? i guess what also i am wondering is if the scanner is in "scan" mode it will eventually pick up the talkgroup id's? Like thier are no "hidden" talkgroups that the scanner will not pick up while it is searching/scanner....sorry if this seems like a dumb question , but i was just wondering?