Abstract: A target junction is illuminated with energy at a fundamental RF frequency and reflections from the non-linear junction are analyzed to determine the type of junction detected. The power output level of a transmitter emitting the illuminating signal is automatically controlled so as to drive the signal strength of the received signals towards a predetermined value, e.g. a minimum threshold value. An indication of the current received signal strength, adjusted by a factor so as to compensate for any automatic adaptation in the actual transmitter power output level, may be provided to an operator.

Abstract: A receiver for analyzing input RF signals includes a first stage that includes an input for receiving one or more RF signals for analysis and a first local oscillator having an output including a first plurality of frequencies. The input is mixed with the local oscillator output in a first mixer to generate a first intermediate frequency spectrum output. A second stage includes a second local oscillator adapted to produce as output a sweep signal traversing a second plurality of frequencies and a second mixer for combining the second local oscillator output with the first intermediate frequency output to generate a second intermediate frequency output.

Abstract: A receiver for analysing input RF signals comprises a first stage (51-55a) which includes an input for receiving one or more RF signals for analysis and a first local oscillator (51) having an output comprising a first plurality of frequencies. The input is mixed with the local oscillator output in a first mixer (55a) to generate a first intermediate frequency spectrum output. A second stage (56-59) includes a second local oscillator (58) adapted to produce as output a sweep signal traversing a second plurality of frequencies and a second mixer (55b) for combining said second local oscillator output with said first intermediate frequency output to generate a second intermediate frequency output.

Abstract: A non-linear junction detector (“NLJD”) detects junctions between two materials exhibiting dissimilar electronic or electrical properties, such as semiconductor junctions or junctions between dissimilar metals. A target junction is illuminated with energy at a fundamental RF frequency and reflections from the non-linear junction are analysed to determine the type of junction detected. The NLJD automatically controls the power output level of a transmitter emitting the illuminating signal so as to drive the signal strength of said received signals towards a predetermined value, e.g. a minimum threshold value. Advantages of the invention are improved system efficiency and the elimination of target saturation effects and unwanted device triggering/indications.