Abstract: A slow wave transmission line is compatible for fabrication on a substrate having an epitaxial layer by creating under the transmission line a buried layer, thus allowing voltage control of the electrical length of the line.

Abstract: Dynamic focus voltages for a CRT are obtained by utilizing the combined parabolic conversion wave shapes for control of the focusing electrode to provide sharp focus at all points in the raster. A current source is coupled to the focus divider chain and the conversion wave shape controls the current in the divider chain by controlling the resistance in a transistor. No high voltage capacitors are required since the dynamic voltages are coupled into the chain near the low voltage end.

Abstract: A programmable cell for a P-ROM (programmable read only memory) matrix includes a bipolar transistor having a fusible link in one of the transistor leads on the substrate. The fusible link is a "necked-down" portion of one of the leads, positioned adjacent the base-collector junction where it is heated by the junction current, causing the links to open at a low fusing current.

Abstract: A pushbutton assembly has an actuating arm with a body portion and an outer end portion connected to the body portion by a narrowed portion. A pushbutton having a cavity and a slot leading from the rear wall to the cavity is retained on the arm by slipping the arm through the slot until the end portion enters the cavity, then twisting the end portion slightly around the longitudinal axis of the arm. The pushbutton can be released by realignment of the arm end portion with the body portion.

Abstract: A two-way AM communications apparatus is provided with common circuitry for biasing the transmitter and receiver on and off alternately while minimizing the switching noise heard in the audio. The push-to-talk button enables either the transmitter or the receiver by means of a transmitter switching network which controls a receiver switching network. When the transmitter is enabled, the audio is muted through a fast-react, slow-decay circuit, and an OR gate and the power amplifier is enabled through a slow-react, fast-decay circuit and a NOR gate. Similarly, when the receiver is enabled, the power amplifier is disabled and the audio unmuted through the same circuitry. A first OR gate is coupled to the channel select switch and noise blanker or other radio circuit to trigger a one-shot multivibrator which in turn is coupled to second inputs of the NOR gate and first OR gates to provide brief audio mute (if receiving) or brief power amplifier disable (if transmitting) during switching periods.

Abstract: An improved tape cartridge release assembly for a player/reproducer apparatus of the type used in a vehicle will automatically release a cartridge when the vehicle ignition switch is turned off, will release a cartridge inserted while the ignition switch is turned off, and will release manually as desired. The assembly utilizes a pair of switches operated by insertion of a cartridge to provide identical voltages to the input and common terminals of a semiconductor circuit controlling the release actuator. The semiconductor circuit, by remaining non-conductive, will prevent release until forward biasing voltage is provided to the controlled semiconductor device as by the ignition switch, the manual release button or other means.

Abstract: When the ignition switch of the automobile is turned off, a solenoid in the tape player is de-energized and the release of its armature pulls a small resilient roller into contact with the tape drive capstan. The capstan forces the roller into a wedged position with a lever arm which in turn activates a cantilevered eject mechanism to eject a tape cartridge. As the cartridge is pushed away from the capstan, it removes power from the capstan. If an attempt is made to insert a cartridge while the key is still "off", the power to the capstan would be restored and, as before, cause ejection of the cartridge.

Abstract: A mode selector mechanism for a magnetic tape recorder/reproducer device for use with a cassette and having a housing, a cassette receiving opening, a tape drive mechanism and a plurality of actuators including a play, a stop and a record actuator, which actuators are movable from an outward at rest position to an inward operative position. A locking mechanism is positioned within the magnetic tape device housing and includes a first portion and a second portion, both portions being engageable with the actuators. When the tape transport is inserted into the tape player device, a solenoid is energized to move the first portion from a first position to a second position wherein it is selectively engageable by at least one of the actuators for holding the same in the inward operative position. The second portion of the locking mechanism is positioned within the housing and is engageable with the play actuator.

Abstract: An improved miniaturized housing arrangement is disclosed for releasably mounting a chassis, such as a printed circuit board, using the contours and the resiliency of the housing itself to retain and release the board. No special tools are required nor any added hardware. The mounting arrangement captivates only small edge portions of the printed circuit board so as to avoid using valuable space on the board that may be devoted to circuitry and the like. The PC board is also fixedly connected to circuitry provided on a non-rigid base ("flex circuit"). The flex circuit is intended primarily for electrical interconnection but also provides a hinge capability for the board when the latter is released. A strain relief device releasably retains the flex circuit within the housing and prevents damage during hingeing action.

Abstract: The assembly has a tuning control shaft which is adjustable over a range of positions to conform to a range of tuner designs. An adjustable guide bracket for the manual tuning pinion gear allows the pinion gear to be positioned along a radius of the crown gear, allowing use of radially wider gear teeth on the crown gear. The clutch-declutch assembly is unaffected by movement of the pinion guide bracket and the entire tuner control and drive gear assembly is preassembled and preadjusted, then positioned with one locking nut.

Abstract: In a pushbutton type tuner assembly for a radio receiver the treadle bar drive gear, which is coupled to the manual tuning knob through the crown gear and the clutch mechanism, is biased into meshed relation with the treadle bar gear through a pair of lever arms mounted for pivotable movement about fixed pins, and a pair of springs. With the end of the treadle bar gear shaft supported in an aperture in the side wall of the tuner, the first lever arm applies a moment to the treadle bar shaft through the bias of a spring secured to the front wall of the tuner, thereby holding that shaft tightly against the supporting aperture wall. The second lever arm applies a moment to the pinion gear shaft through the bias of the second spring which couples the two lever arms together and adds to the moment of the first spring. The two moments provide balanced radial forces on the gears which eliminate backlash and maintain the two gears in a properly meshed relation.

Abstract: An extremely rigid support structure for mounting the tuning coils and for guiding the movement of the core carriage, includes a coil case which is a one-piece molded element having integral indicator guide slot and core carriage guide rods, with the guide rods being fastened to the front portion of the structure by means of screws which pass through the front portion and mate with threaded apertures in the guide rod ends which are in abutting relation with the front portion.