As far as Aeromedical dispatching goes around Minnesota, you have a couple important frequencies. North memorial and Mayo use 155.4 for their dispatching, but they have unique tone codes. Lifelink is all jacked up and last time i spoke with their CEO, he said that they plan to migrate to ARMER, but cost is still an issueso he saw it to be at least 2 years out. I really have no idea how Aeromedical in Duluth is dispatched.
Mayo One and Three(Rochester and Mankato) 155.4
North Air Care One and Three (Lakeville and Redwood Falls) 155.4
North Air Care Four (Princeton) 155.385
North Air Care Two (Brainerd) dotn know off top of my head, but they dispatch on the Brainerd ground frequency
Life Link Metro ANCOM Wireless LTR
Life Link St. Cloud Granite Electronic LTR
Life Link Hutch Hutchtel LTR