Abstract: The invention icludes a device for protecting electronic circuitry from damage, especially damage resulting from high neutron flux density produced by a nuclear explosion. The invention protects the circuitry by disabling its power supply system upon detection of the nuclear event. The power supply system is disabled both by short-circuiting the main power supply, which provides control voltages to various subsidiary powert supplies, and by short-circuiting all the output filter capacitors in the system, which may have a substantial residual charge. The invention periodically and automatically attempts to re-start the power supply system, but the system can be re-started only if the nuclear event detector is not actuated. The circuit made according to the invention is entirely analog, and therefore does not depend, for its operation, on the continued functioning of the circuitry to be protected.

Abstract: An apparatus for use with an amplifier regulates the current through a load according to a drive signal having first and second states and comprises switchless sensing means and polarity correction means. The switchless sensing means provides a sense signal continuously representative of the magnitude of the current through the load without the use of switching circuitry. The polarity correction means is directly coupled to the sensing means and receives the sense signal and is responsive to the status of the drive signal for providing an analog signal continuously representative of both the instantaneous magnitude and polarity of the current through the load.