Abstract: This invention discloses a method of instantaneous frequency measurement. The frequency band of interest is divided into a number of virtual sub-bands. Each sub-band is folded into a common baseband by a band folding down converter. Frequency measurement is achieved in a two part process, part 1 determines the center frequency of the virtual sub-band, while part 2 determines the baseband frequency, the frequency within the virtual sub-band. Both components of the RF frequency are then combined to form the frequency measurement. The frequency determinations for both sub-band frequency and baseband frequency are made by digital processing of the baseband phase measurements. The baseband phase is measured by a multi bit phase sampler, an integral part of the invention.

Abstract: This invention provides a means of providing a continuous signal which corresponds in phase and frequency to a brief instruction signal. The instruction signal is analyzed and the average frequency is determined. The average frequency is used as a basis for synthesis in a direct digital synthesizer or is substituted for the head to tail phase increment in a head to tail repeat synthesizer. The process can be carried out when only a fraction of a cycle is present in the instruction.

Abstract: A method and apparatus for exposed eggs and hatchlings of precocial avian species incubated, hatched, and brooded under artificial conditions to sound recordings made under natural incubating, hatching and brooding conditions to reduce the spread of time over which the hatchlings emerge from the eggs, to reduce the stress experienced by both the unhatched embryo and the hatchling, and to increase the attraction of artificially incubated hatchlings to feed and water during the brooding stage.

Abstract: A lithographic coating and method of framing a lithographic image are disclosed. The method comprises coating at least a portion of a surface of an article with a radiation-crosslinkable polymer, and exposing the coated surface to a pattern of radiation to crosslink the polymer in a lithographic image. The functionalized polymer is a copolymer of an isoolefin of 4 to 7 carbon atoms and para-alkylstyrene, wherein the para-alkylstyrene is functionalized with a radiation reactive group at the para-alkyl group of the para-alkylstyrene.

Abstract: An elastomeric composition comprising a major proportion by weight of a rubber comprising a halobutyl rubber (e.g. 75 to 95%) and a minor proportion by weight (e.g. 5 to 25%) of a copolymer of an olefin, e.g. ethylene, and an unsaturated carboxylic acid e.g. acrylic acid. This composition may be covulcanised with a general purpose rubber e.g. natural rubber, to which it has adequate adhesion. Thus a natural rubber tyre carcass may be covulcanised with a tyre inner liner formed of this composition.

Abstract: A channel unit interface circuit for interconnecting a two-wire, bidirectional signal transmitting means and a four-wire signal transmitting means in a communication system includes a tip terminal line driver, a ring terminal line driver, a voice sense amplifier, a balance network, A/D signal processing circuit, D/A signal processing circuit, filter network, a voice codec/PCM filter, a channel logic circuit, and a DC-to-DC converter. The channel unit interface circuit is suitable for use with substantially all of the different alarm-signalling techniques utilized by the various alarm companies for connecting their equipment to a channel bank coupled to the four-wire means. The interface circuit simulates a transmission line or cable over carrier in the frequency range of DC to 3.5 KHz with an amplitude variation between +110 to -200 VDC.

Abstract: An edge loading cassette holder/loader utilizes an improved ejector/release control arrangement wherein the cassette is loaded narrow end first through a loading receiver opening into a holder/loader platform. The control arrangement includes a first pivotally mounted control arm that is biased to pivot the arm to partially eject the cassette for removal and that also functions as a release control member for the platform. A second pivotally mounted control arm that moves with the first arm and functions as a release member for the platform is also provided. The platform is pivotally movable between an upper loading position and a lower operative position wherein the cassette hub sprockets are engaged by transport drive spindles. The platform is biased to the lower operative position and is moved to the upper loading position by the second control arm.

Abstract: Random access slide projector apparatus is provided for the random access presentation of slide programs. The random access apparatus is responsive to an encoded program tape or to input signals from a local or remote keyboard. The encoded program tape includes predetermined slide address signals as burst format signals corresponding to desired slide positions in the slide tray. The random access apparatus decodes the encoded slide address signals and generates appropriate control outputs to move the slide tray to the desired programmed slide position and project the desired slides. The random access apparatus also provides for the recording of slide address signals in accordance with keyboard entries to prepare random access program tapes. The program tape includes one track for the recording of encoded slide address signals and a second synchronized track for narrative program information to accompany the slide program.

Abstract: Control apparatus including a keyboard is provided for a slide projector to control operation of the slide projector in various predetermined modes to perform predetermined functions. Various functions are executed by the slide projector in response to the keyboard inputs. The keyboard includes an array of digit keys for the numerals 0 through 9 and various other function keys. Actuation of each of the function keys directly corresponds to either a function to be accomplished by the control apparatus or to a command mode input. Actuation of the digit keys provides designation of particular slide address numbers and also provides predetermined mode command inputs. The slide projector and control apparatus include an associated cassette tape recorder/player.

Abstract: A slide tray position sensing arrangement is provided for slide projector apparatus. The slide tray position sensing arrangement is arranged at a detection station. A coded aperture ring is provided that moves in a manner correlated to the movement of a slide tray turntable. The slide tray turntable carries the slide tray that holds the slides for projection and also functions as a tray transport arrangement. The coded aperture ring includes two circumferential arrays of apertures. Each of the apertures in the first array corresponds to a controlled slide position of a first tray type; e.g., an 80 slide tray. Each of the apertures in the second array corresponds to a controlled side position of a second tray type; e.g., a 140 slide tray. The slide tray position sensing arrangement is controllable to selectively sense the appropriate array of apertures corresponding to the slide tray type being utilized.

Abstract: Control apparatus is provided for a slide projector to accurately control rotation of a slide tray to predetermined slide positions of the slide tray and to provide integrated control of the slide change function at each slide position. The control apparatus operates in a forced mode between slide positions and operates in a servo mode to accurately position the slide tray at each of the predetermined slide positions. The detection of the slide positions utilizes a circumferential, apertured ring carried on a movable turntable that also carries the slide tray; the ring including a single incremental position aperture corresponding to each of the slide positions. Dual photodetectors are positioned at a sensing station to sense the respective slide position apertures, to provide differential position feedback detection signals in a servo loop, to interrupt the forced mode of operation and for controlling the stopping and positioning of the slide tray to a selected slide position in the servo mode.

Abstract: A slide transfer and shutter control arrangement is provided for a slide projector including a simplified shutter control arrangement and a positive acting slide sensor arm that is slidably mounted for shifting translation. Slide transfer is accomplished by a vertically movable lifter arm operated by a level wind screw. The level wind screw also operates a cam actuator. The cam actuator moves up and down with the lifter arm to actuate a slider member. The slider member controls the position of the slide sensor arm and provides shutter latch control. The slide sensor arm retains the shutter in the closed position when no slide is present and the slider member is actuated by the cam actuator to release the shutter latch. When a slide is sensed by the slide sensor arm, the slide sensor arm releases the shutter for projection of the slide at the slide transfer station. Slide face tension is appropriately provided by a face tension arrangement under the control of the cam actuator.

Abstract: A servo control arrangement is provided that accurately controls the positioning of a movable member. The movable member is controlled by a motor through a drive train. A coded member is carried either by the drive train or the controlled movable member so as to move in accordance with the controlled movable member. The coded member includes an array of apertures with each of the apertures corresponding to a controlled position of the controlled movable member. In a preferred arrangement, the controlled movable member is a rotary turntable that carries a slide tray for projection apparatus. In that arrangement, each of the apertures corresponds to one of the slide positions of the rotary turntable and slide tray. Feedback information representing the position of the coded member is provided by alternately energized light sources and a single photodetector device.

Abstract: A slide tray position sensing arrangement is provided for slide projector apparatus. The slide tray position sensing arrangement is arranged at a detection station. A coded aperture ring is provided that moves in a manner correlated to the movement of a slide tray turntable. The slide tray turntable carries the slide tray that holds the slides for projection and also functions as a tray transport arrangement. The coded aperture ring includes two circumferential arrays of apertures. Each of the apertures in the first array corresponds to a controlled slide position of a first tray type; e.g., an 80 slide position tray. Each of the apertures in the second array corresponds to a controlled slide position of a second tray type; e.g., a 140 slide position tray.

Abstract: A wet modular film printer having a plurality of removable modules upon which film printer components are mounted including a liquid immersed, capstanless printing head. The printing head immersion liquid is continuously recirculated and filtered by means of a recirculation draw off near the top of the liquid surface and a recirculated liquid return downstream of the printed head. Liquid containing areas are all enclosed and a negative pressure is maintained to remove any noxious vapors. After printing, the liquid remaining on the raw stock and the negative is removed by a series of wipers, an air stripper and a drying column. The drying column uses heated air which flows countercurrent to the direction of film movement so that the air is progressively hotter along the film's path of movement.

Abstract: Apparatus for sequential cyclic operation of a plurality of magnetic tape playing devices. A single side of each tape in each device is played one after the other until all the devices have been operated. Then the other side of the tape is sequentially played. The operation of the device is controlled by logic circuitry responsive to an end-of-tape sensor to operate the next device, switch the tape drive mechanism of the device just operated to play the other side of the tape when activated, and finally to switch off the previously played device. A trouble indicator responsive to the failure of the drive mechanism to be switched from one way of operation to the next is also disclosed.

Abstract: A device for testing coins or other metallic articles is disclosed whereby the article to be tested is introduced into the field generated by the inductor of an oscillator and the change in amplitude of the oscillations resulting from the interaction of the field generated and the article to be tested is measured.

Abstract: The present invention provides an improvement in a card reader type audio visual teaching device. The device employs a card handling mechanism for moving an information card which may contain both audio and visual information, across a record/playback transducing head. A dual track magnetic stripe on the information card carries instructor information or a question on one track to be audibly reproduced by the device which a student can hear through a speaker or preferably a set of headphones. A microphone permits a student to record an attempted repetition or response on the second track. The improvement comprises a multispeed card transport drive mechanism which permits either the student track or both the instructor track and the student track to be driven past the record/playback head at a substantially reduced rate. Additionally, the transport drive mechanism includes a repeat mechanism for returning the card to an initial position.

Abstract: The present invention provides a system for automatically focusing a projected film image by maintaining a predetermined distance along the optical axis between the emulsion on the surface of the film and the projection lens. The system includes a movable carriage for mounting the projection lens and an electro-optic sensor mounted for movement with the carriage for maintaining the predetermined distance. The electro-optic scanner includes a light source and lens assembly for focusing a beam of light onto the surface of the film and a lens for focusing the reflected image onto a dual phototransistor receptor. A servo-amplifier is connected to the output of the dual phototransistor to provide appropriate signals to the carriage drive mechanism to maintain said predetermined distance. The servo-amplifier utilizes both positional and rate feedback to provide faster operation and settling.

Abstract: A printer control unit utilizes a microprocessor and a random-access memory for storing color and cuing information in order to eliminate the need for continuously reading a tape during the printing operation. The printer control unit utilizes a single tape reader and the microprocessor is programmed to permit color tapes, cuing tapes or composite tapes to be read by the single tape reader.