Kind of depends on where in Central NH you're going. The White Mountains start in the northern tier of CNH, and theres several state parks, forests, etc.
Lakes Region Mutual Aid covers a lot of the area and they're on 159.9000/PL 210.7.
If a Search & Rescue occurs in your area, Fish & Game maybe involved using 159.465/$825.
Scan New England, in addition to RR has some good info that might drill down to the specific area.
John