Abstract: A method of operating a thermal inkjet printer having a thermal inkjet printhead that includes the steps of selecting an ink drop volume, selecting a pulse width that will cause the thermal inkjet printhead to deposit an ink drop having the selected drop volume, and operating the thermal inkjet printhead with the selected pulse width and at an operating energy that is greater than a turn-on energy of the printhead for the selected pulse width.

Abstract: A simple and inexpensive method for halftone printing by an inkjet printer is disclosed. Improved halftone printing in an inkjet printer is provided by varying the ink drop volume of an thermal inkjet printhead by controlling the pulse width of the delivered firing pulses.

Abstract: A digital homodyne processing system is disclosed and includes a hydrophone, a preamplifier for amplifying the hydrophone output signal, a heterodyne circuit and a low-pass filter for filtering the amplified hydrophone output, and a digital-to-analog converter. The output of the digital-to-analog converter is compared against sine and cosine references and is integrated as a function of the sine and cosine references. The integration results are processed for detection of a coded waveform.

Abstract: A controlled impedance connector for providing a high density controlled impedance interface between a computer backplane and printed circuit (PC) logic card circuitry having signal carrying conductors and a ground surface imbedded in a dielectric medium at selected spacings to achieve a desired characteristic impedance. A common ground surface is provided for a plurality of signal conductors which are in a selected geometrical relationship with the ground surface. Another embodiment of the invention uses a plurality of microstrips embedded in a dielectric medium and dielectrically separated from a common ground surface to achieve the desired characteristic impedance.

Abstract: A personal audio listening system to be worn by an individual listener is disclosed and includes a pair of speakers mounted within a flexible supporting body which surrounds the back and side portions of the listener's neck. The supporting body may include portions which extend generally forward from both sides of the listener's neck and may be joined by a safety releasable fastener to form a closed loop around the listener's neck. The supporting body includes acoustical and safety padding, speaker grills for protecting the speaker cones and the necessary electrical connections for coupling to an audio signal source. The audio signal source may be external to the supporting body or may be enclosed within the supporting body.

Abstract: A dynamic capacitive memory cell having a storage node formed at the common junction of a fixed access capacitor and two MOS voltage variable capacitors. Data represented in the form of stored charge is written into the storage node through the fixed access capacitor under control of one of the MOS voltage variable capacitors and read out of the memory cell by a sensing device connected between the other voltage variable capacitor and ground. In another memory cell, one of the MOS voltage variable capacitors is replaced by an MOS transistor for preventing excess charge accumulation at the storage node.

Abstract: A switching circuit for controlling the selective electrical energization of a resistive or inductive load by an AC power source such that a switching operation is performed only when the current from the AC power source is nearly zero. Pulses synchronous with the zero crossings of the AC power source are used to trigger one-shots to effectuate appropriately gated delay pulses when the switching circuit is ON and OFF, respectively. A latching circuit connected to an ON-OFF switch activates and deactivates the switching circuit.

Abstract: A push-button switch including a keytop plunger, a base structure for retaining and guiding the keytop plunger, a biasing contact member, and flexible wire contacts. The biasing contact member is a leaf spring mounted in the base structure and actuated into a bowed position by depression of the keytop plunger. The flexible wire contacts are also mounted in the base structure and are engaged by the leaf spring when it is bowed. The complete structure is mounted on a printed circuit board with the leaf spring and wire contacts connected to their respective contact leads on the PC board.

Abstract: A push-button switch including a keytop plunger, a base structure for retaining and guiding the key top plunger, and a pair of biasing contact members. The biasing contact members are a pair of opposing column springs mounted in the base structure and are positioned to be bowed into engagement by the depression of the keytop plunger. Specifically, the column leaf spring members are mounted opposite each other to form mirror images. The complete structure is mounted on a printed circuit board with the leaf spring members connected to respective contact leads on the PC board.

Abstract: A tactile feedback keyboard switch assembly having opposing upwardly inclined leaf springs for biasing an actuating keytop which has downwardly extending members for causing selective engagement of contact members disposed in a diaphragm type contact assembly beneath the leaf springs upon depression of the keytop. A bifurcated action is achieved by providing interconnected contact members for each of the downwardly extending members.

Abstract: An extendable memory organization capable of last-in-first-out or first-in-first-out operation comprising a stack of charge coupled device shift registers arranged such that each register shifts data in a direction opposite to that of its adjoining neighbors in the stack. Gating interconnecting the registers is selectively operable to enable read and write operations at either of the stack and up or down shifting of data in the stack. In particular, the gating and control structure permits refreshing the memory by alternately shifting each stored data word up and down between two storage positions in the stack. In one embodiment, gating and control is implemented in a sandwich structure incorporated into the charge coupled shift register channel.

Abstract: An improved CML (Current Mode Logic) gate having voltage and temperature compensating means for maintaining output levels and input thresholds invariant with fluctations in supply voltage and junction temperature. The output of the compensating means, measured with respect to ground, will track variations in supply voltage on a one-to-one basis except that the output is allowed to vary by one V.sub.be with junction temperature. This output is supplied to the base of the constant-current source transistor which feeds the differential amplifier stage of the CML gate and to the base of a constant current source transistor whose collector is coupled to the base of the non-input transistor of the differential amplifier stage of the CML gate.

Abstract: A FIFO (first-in-first-out) buffer register in which memory data words flow in parallel from an input register through a plurality of registers towards an output register under the automatic control of a one-shot (monostable multivibrator) data transfer system. A one-shot device and a status flip-flop are associated with each individual register in the plurality of registers to asynchronously transfer a data word register-by-register from the input register to the register nearest the output register that is not occupied by a previously inputted data word. The automatic data word transfer system is initiated by either reading a word into the input register or reading a word out of the output register. Logic controls for handling the reading-in and reading-out functions operate asynchronously and independently.