Abstract: The ingestion of air into the print head of an ink jet printer is controlled by a secondary fluidic system. The secondary fluidic system interconnects the ink supply cavity of the head with the primary fluidic system of the printer. The secondary fluidic system includes a valve which is coupled to a venting port of the print head. A rapid decompression regulator is coupled to the valve. The exit port of the regulator is attached to one end of a conduit. The other end of the conduit is disposed in a fluid-containing reservoir. The reservoir serves as an expansion/contraction chamber and keeps air from entering the head even under extreme thermocycling conditions. Likewise, the regulator controls the pressure in the head so that head pressure (P.sub.h) is greater than or equal to ambient pressure P.sub.a. This pressure differential prevents air from entering the head.

Abstract: A wideband ink jet drop generator for breaking up one or more capillary ink streams emanating from the generator, into a regular succession of drops. The drops are of uniform size and uniformly spaced. The generator includes an orifice support plate with a cavity on one surface. A nozzle wafer with one or more orifice is mounted on the opposite surface of the plate. The orifices are in fluidic communication with the cavity. A pair of elongated crystals are disposed on the cavity surface of the support plate. The crystals are configured in spaced relation with the orifices of the nozzle wafer positioned between the crystals along a line whereat pressure waves emanating from the crystal are reinforced.