Portable printer with receptacle for data communication terminal

A portable printer has a housing of impact resistant plastic material. The housing forms a printer cavity and a terminal cavity. A handle is integrally formed as part of the printer housing. Edges of housing elements forming the printer cavity are substantially sealed against each other to protect a printer mechanism, a paper supply, a battery and printer electronics within the printer cavity from water or other contaminants. The terminal cavity housing forms a receptacle for receiving a portable data entry terminal. A circuit board along an edge common to both the printer cavity and the terminal cavity of the housing carries a spring contact connector having a predetermined number of contact springs to engage a corresponding number of contact pads of such a portable data entry terminal when inserted into the receptacle. The circuit board further includes a seal in the region of the wall between the terminal cavity and the printer cavity to maintain the substantially sealed character of the printer cavity. The circuit board further is the mounting board for printer logic functions and for power and data connections to print support elements, to an optional modem and to the printer mechanism. A voltage regulator of unregulated 12 volt power from a vehicle power source includes a switching regulator element which is controlled over a first voltage range. Above the first range printing is blocked and the voltage may then follow the input voltage. A second regulation level may be provided above the first level to protect a low voltage power supply for logic and communications components.