Patent ID: 7999723

Claim:
A device for detecting nonlinear electronic components or circuits of a target, comprising: a junction detector with at least one transmitter and one receiver and at least one antenna, by which a signal with a frequency (f 1 ) is emitted, which signal is coupled into the nonlinear circuit and converted to signals with frequencies (f 2 , f 3 ) that are multiples of the emitted frequency (f 1 ), which are radiated to the receiver and received by the at least one antenna: and a device integrated in the junction detector, by which the frequency (f 1 ) of the narrow-band signal is varied within a predeterminable bandwidth of 10-1,000 MHz, so that a minimal value is obtained for a sum of the attenuation and coupling losses at an optimal coupled signal, wherein the received frequency for second and third harmonics is readjusted according to the emitted frequency.