WMU is a dual-mode 3600 baud TRS. This allows for the older Type-II analog radios to work side-by-side with the newer digital models. Many local government agencies, as a cost-cutting move will buy high-end digital radios for the public safety users, then turn around and purchase analog units for subscribers like the DPW, garbage trucks, etc. However, this will all change as Motorola is saying that they will no longer produce or support analog trunking equipment after 2009.
The MPSCS TRS, is 100 percent fully APCO-25 digital. This system represents the direction that most public safety agencies are heading towards in Michigan. The next big phase will be the integration of MDC technology into the system that will create one seamless data and voice wide-area communications network.
I would not be surprised to see the WMU system get fully upgraded to all APCO-25 within the next five years.
73's
Ron