[TrunkCom] 453 MHz trunked system in the Detroit area

[JEFFREY MICHAEL KENYON]

Hi everyone, I've been hearing what sounds like a Motorola control channel
on 453.055 MHz in the Detroit area.  This is around the Detroit PD's UHF
freqs, and the channel seems to rotate, but I haven't had any idea what it
is, so with the sound I am assuming it is some sort of a trunked radio
system of some kind.  Has anyone else heard this?  If so, do you know what
it may be?  Any information would be appreciated, and thanks in advance.