Abstract: A method and apparatus for setting a time delay value in an electronic fuze of a projectile exiting the muzzle of a gun barrel, in which a single transmitter coil concentrically mounted to the gun muzzle is utilized both to sense the presence of the projectile at the gun muzzle and to inductively transmit a radio frequency signal having a duration proportional to the fuze time delay value to a receiver coil disposed on the projectile. The transmitter coil is energized from a radio frequency oscillator before the projectile is fired. As the front end of the projectile begins to emerge from the gun muzzle, its presence is detected by a change in the transmitter coil impedance, and the transmitter coil is automatically deenergized.

Abstract: A multi-segmented radio frequency excited inductance coil sensor is operaely disposed on the muzzle end of a gun tube for the purpose of detecting the transverse displacement of a projectile from the center axis of the gun tube. The apparatus comprises a combination of sum and differencing amplifiers which combine detected signals into a form which can be used to compute the angle and magnitude of displacement.

Abstract: An automatic velocity delay circuit utilizes the output signal of a radio equency velocimeter for determining the time a projectile takes to pass a sensor located at the muzzle end of a gun. The circuit uses this time interval pulse and clocking pulses to provide an X-ray trigger pulse at the precise instant that the projectile passes an X-ray head located at a selected position along a parallel path of projectile travel, thus insuring a photographic record of the projectile in the muzzle blast region.

Abstract: A differential sensor coil assembly is described which is suitable for plment at the muzzle end of a gun to measure projectile velocity, and which is more capable of resisting propellant gas and muzzle blast wear and erosion effects on the inner coil. A solid sheet coil assembly having a common inner-outer end configuration for inner and outer coil loop include a first plasma arc metal coating, a second ceramic plasma or coating and an expoxy filler means for filling the open areas between the inner and outer loop.

Abstract: A radio frequency coupled differential sensor coil is configured to measure uzzle velocity of a projectile with improved accuracy. An inner loop of the sensor is positioned to be responsive only to the passage of the projectile and the inner and outer loops are equally responsive to exitation from extraneous sources. A differential amplifier circuit is utilized to cancel the extraneous source signals and amplifying the pulse signal generated by the passage of the projectile through a confined radiation plane.

Abstract: An electronic velocimeter for measuring the muzzle velocity of a projectile mploys a conductive coil mounted between the muzzle and an annular conductive shield. The shield and coil are insulated from each other and encircle the trajectory of the projectile. An oscillator means for generating an oscillator signal is coupled to the coil. This oscillator means is responsive to the projectile passing through the coil. A timing means responds to the oscillator to produce a timing signal. This timing signal represents the transit time for the projectile to traverse a predetermined interval of the trajectory of the projectile. Knowing this transit time the velocity is readily obtained.