no a trunked system will have analog voice channels or digital voice channels or both and a control channel, the analog voice will sound like normal voice, digital voice will sound usually like white noise/open squelch and the control channel will sound like an engine running, or in the case of an EDACS/MA-com control channel, a diesel engine

www.radioreference.com is a good site to search out you're local conventional frequencies and trunked radio systems in use in you're area.

mark