Primary control channel for Anoka County should be 853.3875. Blaine PD is normally heard on the South Main, or "Channel 1". However, from about 3 AM to 11 AM they have the North and South channels patched and the traffic is sometimes heard on Talkgroup 810, which is the North Main, or "Channel 7".
Also if you weren't aware, the "David" units are Blaine PD.
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