John,I use the control channel method to track the MSP systems. As
mentioned, they do not change. I've had great success with this
from day one, and it certainly saves a bunch of slots better
used for conventional stuff. I'm not sure what the Western or
Central Ma. sites are using but here are the rest:
Zone 05 (Boston) 860.9875
Zone 03 (SE Mass) 859.8375
Zone 04 (Cape Cod) 860.2375
Zone 06 (Lower Cape Cod, small system, eventually will be
integrated into the Zone 04 system) 857.2125
Hope that is of some help. Check the link below for related
info at my website.
Scott
Cape Cod Trunking Info
Cape Cod Scanner Radio Guide