March 2014 my overview of 911 dispatch system
http://www.barnstablepatriot.com/home2/index.php?option=com_content&task=view&id=35726&Itemid=30
Lets look at the real facts - which no news reporter will ever figure out -
Barnstable County Sheriff - runs the county jail and the "County" dispatch center, and maybe some crime scene detectives - he has no patrol units like a typical USA Sheriff Dept has - the "County" dispatch center serves as PSAP and / or dispatch point for some towns on Cape Cod - the "County" dispatch center also serves as the fire mutual aid control point - and sends out police BOLOs
All agencies on Cape Cod use the State TRS, and most have local independent radio channels also
Towns in Cape Cod
Provincetown - local police/fire dispatcher serves as PSAP and dispatch point (DP)
Truro - local police/fire dispatcher serves as PSAP and DP
Wellfleet - local police dispatcher serves as police DP - 'county' serves as PSAP and fire DP
Eastham - local police/fire dispatcher serves as PSAP and DP
Orleans - local police dispatcher serves as police DP - 'county' serves as PSAP and fire DP
Brewster - local police dispatcher serves as police DP - 'county' serves as PSAP and fire DP
Chatham - possibly separate local police and fire dispatchers serves as DPs - 'county' serves as PSAP
Harwich - local police/fire dispatcher serves as police/fire DP - 'county' serves as PSAP
Dennis - local police dispatcher serves as PSAP and police DP - 'county' is fire DP
Yarmouth - local police dispatcher serves as PSAP and DP - FD serves as fire DP
Barnstable - local police dispatcher serves as PSAP and police DP - 'county' is fire DP for Barnstable FD and West Barnstable FD - Hyannis FD dispatcher serves as fire DP for Hyannis FD - Centerville FD dispatcher serves as fire DP for Centerville FD and Cotuit FD
Mashpee - local police dispatcher serves as police DP - 'county' serves as PSAP and fire DP
Falmouth - local police dispatcher serves as police DP - local fire dispatcher serves as fire DP - 'county' serves as PSAP
Otis AFB - 'county' serves as PSAP and fire DP - (?police dispatcher serves as police DP?) - Coast Guard dispatcher serves as ambulance DP - military serves as DP also probably for other security forces
Sandwich - local police dispatcher serves as PSAP and police DP - local fire dispatcher serves as fire DP
Bourne - local police dispatcher serves as PSAP and police DP - 'county' serves as fire DP
In this system there are no "on call" dispatchers (ie someone who responds from their home to man a radio console at a fire station when there is an emergency). There are no "partial time / dual hat" dispatchers either (ie - fireman answers phone, dispatches call, and then drives fire truck, leaving PD to answer phones).
Maybe someone else can sit down and figure out how many different configurations this is. Maybe a dozen.