Modems; Communication modems; Interface network modems; Modems for communications networks; Fixed radio apparatus for voice transceivers; Fixed radio apparatus for voice transmission; Fixed radio instruments for data transceivers; Fixed radio instruments for data transmission; Mobile radio broadcasting units; Network connector for radio networks; Radio apparatus; Radio transceivers; Voice signalling apparatus for use with mobile radio systems; Voice signalling apparatus for use with radio paging systems; Radios; Radio receiving sets; Radio broadcast receiving sets; Portable radios; Mobile radio receiving apparatus; Electronic radio apparatus