A printing device performs band printing during two-way printing, wherein the band printing uses black pigment ink and dye ink. The display support apparatus further includes a mechanism for providing a constant orientation in relation to the base for the plane bisecting the range of rotation of the second arm about the pivot axis between the first arm and the second arm even as the first arm moves pivotally relative to the base. Depending on a level of a control signal to a VCO contained in a frequency phase-locked loop for use in clock generation, an out-of-synchronization detector makes determination of abnormalitynormality. The toroidal flow pattern has diametrically opposed cross-sections which alternate in size to cause the jet to move in radial paths and also in tangential direction and thereby choose a different radial path at each sweep, whereby there is a random sweeping of the jet issuing from the outlet aperture over the area. TiN films on metal substrate exhibiting the stoichiometric TiN and Ti2N were synthesized in a mixed N2Ar plasma with initial gas filing ratio of preferably 1:3 under the following conditions: total initial gas filing pressure of at least about 40 mTorr, plasma current in the range of about 2A to 3A and plasma discharge potential in the range of about 125V to about 150V. The oxygen generator is configured to enrich the oxygen content of air flowing from the air supply duct to the breathing gas duct.