Modular electronic measuring and printing unit

A compact, modular, electronic measuring unit (10) constructed for enclosure within a small, portable housing (12) having a removable front wall (40) to provide access to the enclosure (28) formed within the housing (12). A measuring and indicator circuit card (60) is mounted within the enclosure (28) adjacent the front wall (40) while a power circuit card (58) is mounted within the enclosure adjacent the rear wall (22) thereof. Manual control units (44, 52, 54) are mounted on the front wall (40) of the housing (12) and are removable therewith. A moving dot matrix printer (56) is mounted within the housing (12) and is connected to receive data from the measuring and indicator circuit (60). This printer (56) is activated by one of the control units (50) on the front wall (40) of the housing (12), and includes a printer unit (116) which is driven in a first plane during the printing of a character on a record medium (178) and a record medium drive unit (136, 148, 150) which drives a record medium (178) in a second plane transverse to the first plane during the printing of a character.