Abstract: A Gunn microwave transmitter/receiver is coupled to an antenna to transmit microwave signals perpendicularly to a surface of a motionless or a slow moving object and to receive waves reflected from the object. The frequency of the oscillator of the Gunn transmitter is controlled by the output of a sawtooth wave generator. Accordingly, the output of the transmitter is cyclically and linearly varied from a first transmitted frequency to a second transmitted frequency. An accurate timer cyclically resets the both the sawtooth generator and digital processing circuitry.The wave reflected from the object and the signal transmitted at the time of arrival of the reflected wave are processed to detect the difference between the reflected wave and the transmitted wave, or the first negative to positive zero crossing that occurs after reset. This event initiates a time window which is terminated at the end of the cycle in which the relationship is detected.

Abstract: Credit card blanks are manufactured with a plurality of random, secure codes (24) such as randomly applied infrared readable bits. A card encoding apparatus (B) includes a secure code reader (32) for reading the secure code from one of the blanks. The secure code and account information are operated on by an encoding algorithm (36, 38) to generate a verification code which is electromagnetically recorded (40) or embossed (42) on the card. In conjunction with a credit card transaction, the merchant passes the credit card past an electromagnetic read head (50) and an infrared read head (52) to read the electronically encoded account information, verification code, and secure code. A keyboard (54) enables the merchant to manually enter this data if the electromagnetic recording should be unreadable. The verification apparatus operates on the account information with a verification algorithm (66, 68, 70) to generate an answer corresponding to the verification code.

Abstract: A credit card (10) has a layer (28) of high coercivity magnetic material which is of a sufficiently high magnetic coercivity that once its dipoles are polarized, they are unable to be returned to a randomized distribution. The card is embossed with a man-readable code (30) and is electromagnetically recorded with a man-nonreadable code. Particularly, the electromagnetically recorded code includes an account code (42, 44), a visual comparison algorithm code (50), a visual comparison code (52), an electronic comparison code (54), a card identification number (56), and a personal identification number (58). A reader (60) reads the account code and produces a man-readable display (102) of the electromagnetically coded account number. To verify that he has compared the display with the account number on a receipt, the merchant marks the symbols on the receipt which correspond to the highlighted symbols of the display.

Abstract: A television system and method are disclosed for monitoring and indicating changes in a scene from which electromagnetic radiation, such as visible light, emanates. A television system including a television camera scans the scene in known raster fashion in a series of image frames, producing an amplitude modulated video signal describing the energy intensity distribution of the scene. Clocking and gating circuitry triggered in synchronism with television camera synchronization signals defines a set of predetermined discrete spaced locations of the raster during each image frame and samples video signal amplitude at each of the defined locations. The same discrete locations are sampled during each frame. Video selection circuitry, during a succession of sampling periods, inputs in real time a representation of each video amplitude sample to one of several storage channels of a multi-channel memory system including a multi-channel counter.

Abstract: A guidance system for positioning a welding apparatus with respect to a seam or joint to be welded by sensing changes in the surface of the seam. The torch of the apparatus is mounted upon and positioned by a motor-driven cross-slide providing both horizontal and vertical movement.A probe is adapted to follow the reference surfaces. Two variable resistors within the probe detect horizontal and vertical deviations of these surfaces. A voltage on each variable resistor is used to generate pulses which are applied to a SCR network through which power is supplied to the corresponding slide positioning motor. The voltage supplied to the motor corresponds in magnitude and polarity to the deviation in the direction of the path being followed by the probe and welding apparatus.The invention also includes a circuit for disabling the motors when the respective cross-slides reach the limits of their travel.

Abstract: A guidance system for seeking, following, and maintaining the position of a welding apparatus with respect to a seam or joint to be welded by sensing changes in the surfaces, hereinafter called reference surfaces, at or adjacent to the seam. The system includes a probe adapted to detect and follow the reference surface(s) and to detect changes and deviations in the vertical and/or horizontal components of these surfaces, respectively. The torch of the welding apparatus is mounted upon and positioned by a motor-driven cross-slide providing both horizontal and vertical movement. The probe is mounted on the torch or on its own slide, which may be either on the torch or separate therefrom.

Abstract: Apparatus for guiding a welding torch, slave mechanism or the like, including a probe or guide wherein the torch follows or traces the path of the probe, both as the probe (1) follows a basic straight, curved, or otherwise changing spatial or three dimensional path and (2) as it departs from the direction of the basic path or seam because of defects of rather short duration, or of sudden changes in lateral and/or vertical abutments or surfaces against which the probe travels, wherein the path of the welding torch or slave mechanism is caused to trace the path traveled by the probe or guide, and not merely to duplicate the path in a stepwise functional relationship therewith.