Abstract: A synthesizer is provided to include a phase detector, a loop filter, a current source and two current sinks. The current source and the second current sink selectively supplies current to and from the loop filter, respectively. The first current sink selectively sinks current from the current source. Responsive to signals from the phase detector, a controller actuates the current source on prior to switching at least one of the first and second current sinks.

Abstract: A manufacturing process for a mutlilayer thermoplastic printed circuit substrate (200) begins with a thermoplastic core substrate (202) having a printed circuit pattern (204) on a surface (202A) of the core substrate. Either fully reacted or partially reacted thermoplastic material is dissolved in a suitable dissolving agent and then applied in the liquid state over the surface (202A) of the core substrate. Application is by spraying, dipping, spinning or rolling. This results in a layer of liquid thermoplastic material covering the printed circuit pattern on the core substrate. The dissolving agent is then removed from the thermoplastic layer, leaving behind a uniform, dry hard, dielectric film of thermoplastic resin (206). Using photolithographic techniques, a via (206A) is opened up in the dielectric layer. If the starting material for the dielectric layer was partially reacted thermoplastic resin, the dielectric layer is now fully cured.

Abstract: A display system includes a liquid crystal display, a light guide behind the display, and light emitting diodes. The light guide is a molded slab of clear material with a front display surface a rear surface and six bordering surfaces with two planes depressed into its rear surface and having two hollow half cylindrical extensions integrally molded with closed top and bottom ends. The rear surface and bordering surfaces and outer surface of the extensions are coated with reflective white paint. These extensions receive light from surface mounted LED's which are positioned directly below the extensions to redirect the light into the light guide.

Abstract: A switch assembly includes a housing 25 having a recess 26 with switch contacts 23 in the recess. A flexible sheet 21 is affixed to the housing and covers the recess. The flexible sheet carries a conductive contact 22. When the sheet is depressed, its contact engage the contacts in the recess to complete an electrical circuit. The housing can be formed as a molded plastic member with the switch contacts being formed on the plastic member.

Abstract: A synthesizer circuit with spur compensation utilizes fractional division in the synthesizer loop. Two accumulators are utilized for determining the divisor value N. The capacity of the two accumulators is selectable. An offset value is selectively introduced into the accumulators in order to produce a waveform having an acceptable spurious content.

Abstract: A method of demodulating a quadrature modulated signal includes first receiving the signal. The rf signal is then quadrature demodulated to produce in-phase and quadrature signals. One of these signals is filtered to produce a correction signal which is used for phase and amplitude correction. Both of the demodulated signals are again quadrature demodulated to produce the output signals. The second demodulation can be accomplished utilizing a correlation decoder. The applied correlation pulse includes a subcarrier component.

Abstract: A shorted component 10 is provided on a module 18 whereby the shorted component 10 is trimmed to either a capacitor 22 or an inductor 30. In the same step, the capacitor or inductor is further trimmed to a predetermined value of reactance.

Abstract: An improved voltage controlled oscillator (VCO) is provided whereby the control voltage is utilized for modulation compensation by a modulation compensation network (90). The modulating signal is variably coupled into the voltage controlled oscillator (70) to compensate for the variation in the VCO's gain factor to yield a constant modulation level over a frequency band.

Abstract: The preferred housing includes an integrally molded thermoplastic base (102) and cover (104) assembly. The cover is joined to the base by a living hinge (106) and a peripheral wall (108) extends around the perimeter of the base. In one embodiment, the antenna is a wire loop (204), the wire being wound in an external circumferential groove (202A) in the peripheral wall or, alternatively, integrally molded into the peripheral wall. Other embodiments use printed circuit loop antenna patterns that are preferably vacuum deposited directly onto the thermoplastic base and/or cover. When the antenna pattern is disposed on both the cover and the base, a portion of the antenna (e.g., 1002K) is also disposed on the hinge to join the main portions of the antenna on the base and cover. In one embodiment of the printed circuit loop antenna, the plane of the loop lies parallel to the base and may include one or more turns or loops (e.g., 402C, E, G and J). In another embodiment, the loop includes a 90 degree bend (e.g.

Abstract: A coaxial connector includes a housing carrying an insulator. The insulator carries a center contact with a spring biasing the cneter contact. A volute spring engages the housing and provides the ground or shield contact. The housing is formed of two halves with the volute spring and alignment pins holding the housing halves together. A coaxial cable has its shield clamped between the housing halves for providing the ground connection to the volute spring. The coaxial cable center conductor is connected to the center contact within the housing.

Abstract: A method for effecting high density solder interconnects between a substrate and at least one metalized film having through holes therein is provided. Solder is first applied to metalized portions of the substrates and the solder is then subject to a reflow process to provide reflowed solder. Pressure is applied to the reflowed solder during a second reflow process to provide prestressed or shaped solder. The metalized film is then positioned with at least one metalized portion adjacent to the shaped solder. Heat, as from a laser, is directed through the through holes in the film to melt the solder and form solder interconnections between the substrate and the metalized film.

Abstract: A battery charger includes a first charger for providing a first battery charging current and a second charger for providing a second battery charging current. A switch is provided for manually actuating the second charger. A timer times the second charger cycle. The timer is used to initiate the discontinuation of operation of the second charger. When the second charger is operating, the timer is inhibited from being reset. When the first charger discontinues supplying a charging current, the battery charger is conditioned to again permit actuation of the switch to reset the timer and allow operation of the second charger.

Abstract: A speaker grille assembly (800) includes a speaker grille 410), a felt (200), and a speaker (300). The speaker grille has a front surface (420), and a rear surface (430). The speaker grille (410) has plurality of equally spaced channels (440) for passage of sound. The sound channels (440) are formed such that that the rear surface port (422) is substantially larger than front surface port (411) thereby enhancing acoustic power transfer by increasing the effective sound passage space.The sound channels (440) can be formed such that the passage through the grille (410) are provided with either gradual or sudden transition from front port (411) to the rear port (422) resulting in a larger rear surface apertures.

Abstract: A single input, differential output amplifier (50) includes two Gallium Arsenide field effect transistors: one arranged to form a common gate amplifier (55) to provide a non-inventing output (60), and the other arranged to form a common source (65) amplifier to provide an inverting output (61). The input of each FET is connected to receive an input signal simultaneously thereby minimizing phase delay in the differential output signals. In another aspect of the invention, the non-inverting stage (55) is incorporated into the biasing network for the inverting ampllifier (65).

Abstract: An electrical socket is provided which includes a connector element to which a soluble temporary housing is attached. The socket is suitable for mounting on a printed circuit board or other substrate. The temporary housing provides a handle which an automatic component placement machine can grip. Once the socket is installed in an aperture in the printed circuit board, the housing is removed via solvent to free-up space on the board.