Rochester District 2100 base frequency is 154.920, it is used by both dispatch and mobile. I lived in Rochester area from July 1985 until January 2004 and visit the area about 12 times a month, I have heard MNSP Rochester Dispatch within the last 2 weeks. The old mobile frequency was 158.910. When I am in the Rochester area, I am about 1/2 from the District 2100 Hq, I would be located near 41st St NW just off of US 52.