A remote radio listenership monitoring system including a digitally tuned scanning receiver disposed in an area adjacent to automobiles carrying radio receivers which radiate intermediate frequency signals corresponding to the frequency being amplified by that radio receivers, the receiver utilizes a narrowed filter scheme to sense the presence of an intermediate signal of a predetermined power level and rapidly polls a plurality of selected target frequencies. The system compiles target "hits" in a local memory device to create a database for that local unit. Periodically, the databases are transferred to a central processing station where individual local unit databases are compiled into a comprehensive report. Communication between the remote local units and the central processing station may be accomplished through a hard wired or cellular link. Updates to the system software and new target frequency data are transferred back to the remote units by the central processing station.