Abstract: A system for carrying articles at the front torso of a human being is disclosed. A substantially rigid article-carrying frame is connected to the front of a harness or backpack worn by the user. The frame transmits the weight of the front-carried articles to the front of the user's hips. The system accommodates bending movements of the user's torso by providing, for example, a variable-length mechanism, or a bending mechanism, or a folding mechanism, or a sliding connector mechanism, or any other equivalent accommodation mechanism that will allow the system to accommodate bending movements of the torso of the user.

Abstract: The system and method for switching a radio frequency (RF) signal between mixers can provide a large automatic gain control (AGC) range while maintaining low noise levels by using a switching circuit to select between at least two mixers that are switched between a common load using reverse biasing. To turn off a specific mixer, RF inputs to that mixer are reverse biased, which shuts off the current to the load. The full AGC of the switching circuit is approximately the sum of the AGC of each mixer. Each mixer has a limited AGC range, which limits the amount of current swing needed for the full AGC of the switching circuit. By dividing the switching circuit between two or more mixers, the transistor devices in each mixer may be sized appropriately with respect to the current levels being used in each mixer. For instance, in a mixer designed specifically for low noise applications, the transistor devices can be very large.

Abstract: A signal conditioning circuit including power terminals adapted to be connected to a direct current power source, sensor terminals adapted to receive a direct current signal from at least one electrical sensing device and output terminals adapted to be connected to an electrical resistance. The conditioning circuit includes an inverter connected to the power terminals for generating an output signal of opposite polarity to the signal received at the power terminals. An adjustment mechanism is connected to the output terminals for receiving the inverter output signal and adjusting the magnitude of the signal received at the sensor terminals to a desired level. In a second mode of operation, the circuit includes a second set of sensor terminals and the adjustment mechanism operates to deliver an output signal proportional to the difference between the signals received at both the first and second sensor terminals.

Abstract: A high speed, high accuracy surface temperature measuring probe of the contact type including a thin-film platinum resistance thermometer mounted in a support assembly having a low specific heat and low conductivity with a thin pure copper end cap in thermal contact with the resistance thermometer and extending along the sidewalls of the probe for a short distance.