Actually, Summit County is using VHF for their primary comms still. A while back they had an RFP out to build their own P25 VHF system but it sounds like they will be doing a hybrid approach instead and plan to use both VHF and the state DTRS system (much like what Boulder County does).
The two primary dispatch channels for public safety are "Summit Law" (listed in the screenshot below as SummitCoLE) & "ES Dispatch" (emergency services dispatch, listed in the database as "Summit Co FD/EMS").
The VHF Ops chs are mainly used by fire/ems when responding to incidents but law also has the ability to use them. Each ops ch is assigned by location, each has repeaters located at different locations. The CMD chs are used the same way, but are repeated throughout the county.
As far as DTRS goes, those channels are used for ops/tac chs when coverage is bad or transporting outside of the county. Both CSP and the county also have radios on each system as well (it's not un-common to hear them on each other's systems). I'm sure the use of DTRS could be changing anytime in the near future once they start implementing their new "Hybrid" setup.
Look again, they appear to operate on
this TRS. The locals should be able to tell you if any of the VHF conventionals listed are still active
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