Abstract: An electronic hold circuit for a telephone which is actuated by a hold command signal produced by a momentary depression of the telephone hook switch. The hold circuit is connected across the telephone lines and includes circuitry for discriminating between a hold command signal present on the telephone lines and dialing, ringing and hand-up signals. When a hold command signal is detected, a holding impedance is connected across the telephone lines thereby maintaining the connection at the central office.

Abstract: A temperature achievement controller for controlling the temperature of a device which is heated by a heating unit in accordance with a predetermined temperature versus time schedule. The controller includes apparatus for producing an analog signal which corresponds to the achieved temperature of the device under test and apparatus for producing an analog signal which corresponds to the desired temperature versus time schedule. An error signal equal to the difference between the achieved and desired temperature is generated and coupled to a three mode control unit which produces a control signal proportional to the sum of the derivative of the error signal, the integral of the error signal and the error signal itself. The control signal is received by a duty cycle modulator which controls the ratio of power on time to power off time of the power applied to the heating unit in accordance with the magnitude of the control signal.

Abstract: A radio controller for radio control of model vehicles and the like. The controller can be placed in a control mode wherein vehicle functions such as motor speed, direction, horn and lights are controlled by control signals. In addition, the controller can be placed in a voice transmission mode wherein an audio signal is transmitted to the vehicle and broadcast from a speaker mounted on the vehicle. The receiver of the radio controller is switched from the control mode to the voice transmission mode by way of the control signals. When the receiver is placed in the voice transmission mode, the control signals are ignored with switching to the control mode being accomplished by receiver circuitry which detects a momentary absence of the transmitted carrier signal.

Abstract: A hand-held electronic program playing device having a flat panel electro-optical display unit incorporated in a housing, is disclosed. Circuitry suitable for driving the display unit and manually operable controls for providing a plurality of control functions are incorporated in the housing. A replaceable cartridge unit which fits into and mates with the housing incorporates a microprocessor and supplementary circuitry. The cartridge unit can include a transparent overlay which incorporates one or more graphic patterns. When the cartridge is placed into the housing the overlay is disposed relative to the display unit so that the visual image of the display unit is viewed through the overlay. The microprocessor and overlay in the replaceably cartridge define the program such as a game that can be played by the housing and cartridge combination.

Abstract: A voice discriminating system is disclosed which includes input circuitry for a pair of microphones, circuitry for detecting the presence of voiced sounds inputted to the microphones, selectively enabled circuitry for detecting the presence of unvoiced sounds inputted to the microphones, and a microcontroller which executes functions under the control of the presence or absence of voiced or non-voiced sounds inputted to the microphones. The disclosed system further includes a display circuit and a sound circuit that are controlled by the microcontroller for the purpose of playing games wherein the players provide spoken commands to the microphones.

Abstract: An optical imaging system for a copier comprising at least a pair of multilens plates made from the same mold to have matched surface configurations. One of the pair of multilens plates is arranged to be rotated from the position of the other multilens plate through 180 degrees about an axis parallel to the longitudinal direction of the other multilens plate. A reflecting surface is positioned parallel to the axis of rotation for deflecting the optical path between the pair of multilens plates once or an odd number of times whereby a clear image is provided despite imperfections from molding.

Abstract: The golf swing training apparatus has a plastic grass mat that shows the proper positions for the feet and hips in the modern one piece golf swing, in which the body and the golf club, have to be coordinated. It gives the golfer the positions for putting, chipping, pitching, iron shots, and wood shots.A plastic or rubber guideway for the golf club is built into the mat and it shows the golfer how to position and also how to rotate his shoulders properly. The guideway shows visually, mentally, and physically how to swing the club through properly in the one piece, moder golf swing. That is on are that starts straight back, then to the inside, on the backswing. On the downswing it comes down inside, then straight through at the ball area, then back inside.There is a novel tension spring in the guideway that squares the golf club face to the target and makes the ball go straight.The back end of the guideway is flared out so that incorrect swings are corrected while the golfer is learning.

Abstract: Circuitry for detecting and correcting false equilibrium conditions generated in data modems by sudden changes in gain of an associated transmission system including a false gain detector which detects a low rate of production of symbols of largest magnitude and triggers a final gain circuit which initially jumps the overall system gain and thereafter adaptively adjusts the gain jump to the correct value.

Abstract: A public-key data encryption system employing RSA public-key data encryption including a message encrypter capable of encrypting messages using a non-secret encryption key, a transmitter-receiver coupled to the message encrypter which transmits or receives an encrypted message to or from a remote location, the transmitter-receiver also being coupled to a decrypter capable of decrypting a received encrypted message using a decryption key which is a secret input to the decrypter, and an encryption-decryption key generator, including a microprocessor or other large-scale integrated circuit or circuits formed to generate a sequence of prime numbers beginning with a selected known prime number having a length relatively short with respect to the desired length of the last in the sequence of prime numbers, and which is constructed to form the sequence of prime numbers in the form hP+1 where P is the preceding prime number in the sequence, and to test hP+1 for primality by first determining if hP+1 has a GCD of 1 wi

Abstract: A toy track system having an electro-optical sensing device in the roadway senses the passage and identity of a plurality of individual cars on that roadway and provides the sensed information to a microprocessor based operator control panel. The operator control panel provides visual information to the operator by individual LED's and an alpha-numeric display and provides audio information by a speaker. The operator control panel receives information from the operator through a 4.times.4 matrix keyboard. The microprocessor of the control panel is programmed to permit the operator to test his skill in manipulating the train cars in a dictated sequence and within a certain time frame. The operator can also direct the control panel microprocessor to activate a plurality of accessory devices in the system in a desired sequence and time span.

Abstract: A camera capable of informing a photographer of conditions of a camera by means of human voice, which is adapted to arrange improper camera operating conditions in a predetermined order, and to give them as warnings in a sequential manner. Further, prior to every warning statement, precursory sounds are adapted to be given, to call attention of the photographer. In addition, a camera capable of narrating the explanation of the way to handle the camera is disclosed.

Abstract: The present invention is directed to a compact lens system equally operable in both air and water, comprising a first lens group having a front surface directly facing the air or water medium, the center of the curvature of the front surface being located approximately at the entrance pupil of the lens system, and a second lens group located at the image side of the first lens group with an air space formed between the first and second lens groups. The air space and design parameters being selected in the lens system so that the field curvature of the lens system is mainly changed without any substantial change in other aberrations when the air space is changed, wherein the air space is changeable by a predetermined value in response to the change between use in air and use under water for maintaining a relatively flat image surface.

Abstract: An exercising device for strengthening and developing the hand, wrist, forearm and pectoral muscles. The device includes an elongated rotating pin having a central portion with a circular cross-section and gripping portions located on either side of and coaxial with the central portion. The central portion is received by a clamping mechanism which is held stationary by a mounting apparatus. The clamping mechanism includes an adjustment for varying the frictional force exerted by the clamp on the rotating member. Further included is a laminated liner disposed between the clamping mechanism and the rotating member comprised of a layer of rubber and a layer of self-lubricating plastic.

Abstract: A simulated portable doctor's office play set is provided with a diagnostic capability of prescribing specific medication for specific ailments. The diagnostic instrument including a magnet therein is capable of not only contacting the patient, but also a display panel to make visible a particular remedy. The play set further has a capacity of dispensing a color-coded medication container that corresponds to the remedy shown on the display panel.

Abstract: A hand-held electronic sound generator, comprising a one or more oscillators and a noise generator, each acting singly, mixed or gated in combination to produce a variety of interesting sounds. The device may be operated continuously or as a momemtary pulse with decaying volume. Power is used only when sounds are being generated to conserve battery power. The frequency of the oscillators or noise generator may be varied to change the characteristics of each individual sound combination.

Abstract: A toy car adapted to travel on a track assembly is disclosed. The toy car includes a motor coupled to a drive train which drives the car forwards regardless of a direction of rotation of an output shaft of the motor. The drive train includes a first set of gears coupled with a first one-way clutch to drive an axle of the car when the output shaft of the motor rotates in a first direction. The drive train also includes a second set of gears coupled with a second one-way clutch to drive the axle when the output shaft rotates in a second direction. The first set of gears represent a higher gear reduction ratio from the output shaft to the axle than the second set of gears whereby a speed of the forward motion of the car may be altered by reversing the direction of rotation of the motor. The motor of the car draws electric power from the track assembly.

Abstract: A toy stove assembly includes a housing member configured to simulate a stove with an upper burner portion. A cooking vessel has an apertured false bottom connected to a conduit that extends to the exterior of the cooking vessel. Pressurized air is generated and connected to the conduit so that the air can be introduced into the cooking vessel to simulate boiling of any liquid substance in the cooking vessel. A toy kitchen sink can also optionally be included with the same motor that provides the pressurized air providing a pumping action for delivering water through a faucet.

Abstract: A control unit for controlling a vibratory bowl feeder which is effective to maintain, for varying feeder loads, a constant preselected amplitude of bowl feeder vibration at a vibratory frequency which coincides with the changing mechanical resonant frequency of the feeder system. The control unit includes a sensor which detects the amplitude and frequency of feeder bowl vibration, a frequency control loop and an amplitude control loop. The frequency control loop is responsive to the detected frequency of vibration and provides an oscillating signal which coincides with the resonant frequency of the system. The amplitude control loop is responsive to the detected amplitude of vibration and includes a variable gain amplifier which amplifies the oscillating signal to provide a feeder driving signal which causes the feeder to vibrate at the system resonant frequency at a preselected amplitude.

Abstract: A toy racing car is provided having a configuration to simulate a racing car such as a drag car. A support member is attached to the body of the car at a predetermined location to receive a weighted member such as a coin of monetary value. The addition of the coin alters the location of the total center of gravity of the car and positions it so that upon the application of a small additional force, the front wheels will be lifted off the ground to provide an impression of high speed acceleration.

Abstract: A power conversion system comprising a combination of a liquefied natural gas vaporizing plant and a fuel burning power generating facility is disclosed. The liquefied natural gas vaporizing plant utilizes the cryogenic capacity of the liquefied natural gas to produce liquid air which is pumped to a high pressure by a liquid air pump. The liquid air is then brought into a heat exchanging relationship with air drawn into the vaporizing plant so that the high pressure liquid air is converted to high pressure gaseous air. The high pressure gaseous air which represents recovered reversible energy of the liquefied natural gas is fed into a combustion chamber of the fuel burning power generating plant. Since the power generating facility requires no significant output of power to drive a compressor to compress ambient air prior to its entry into the combustion chamber, the power generating facility is operated at a high efficiency.