Modular electronic measuring and printing unit

A moving dot matrix printer for forming alpha and numeric characters on a recording medium comprising support means, elongated mounting means mounted upon said support means, a unitary print assembly means mounted upon said elongated mounting means for movement in a first path along said elongated mounting means between a start and a stop position, said unitary print assembly means being operative to mark an adjacent record medium, printer drive means operative during the formation of a character to selectively move said unitary print assembly means along said elongated mounting means between spaced points in said first path, said printer drive means including movable cam means mounted to contact said unitary print assembly means, said cam means operating to move said unitary print assembly means in said first path and bias means mounted to engage and bias said unitary print assembly means toward and into engagement with said movable cam means, record medium drive means mounted upon said support means and operative to position a record medium relative to said unitary print assembly means for marking thereby, said record medium drive means operating during the formation of a character to move said record medium in a second path transverse to the first path of movement of said unitary print assembly means.