Abstract: This specification discloses a system comprising a source for selectively applying a test signal to a selected conductor at a first end of a cable and a detector having a plurality of input terminals for connection, respectively, to at least some of the conductors at the second end of the cable. The detector operates to perform individual comparisons of the amplitudes of the signals on its input terminals with the amplitude of a decreasing reference signal and to produce a signal after a predetermined number of such comparisons in excess of a predetermined value have occurred. This last-mentioned signal causes a display unit to indicate the input terminal on which appeared the signal that produced the last comparison in excess of the predetermined value.

Abstract: The present invention additionally comprises a method and apparatus for generating and mixing signals for frequency-domain lifetime and spectral fluorometry. The present invention comprises a plurality of signal generators that generate a plurality of signals where the signal generators modulate the amplitude and/or the frequency of the signals. The present invention uses one of these signals to drive an excitation signal that the present invention then directs and transmits at a target mixture, which absorbs the energy from the excitation signal. The property of fluorescence causes the target mixture to emit an emitted signal that the present invention detects with a signal detector. The present invention uses a plurality of mixers to produce a processor reference signal and a data signal. The present invention then uses a processor to compare the processor reference signal with the data signal by analyzing the differences in the phase and the differences in the amplitude between the two signals.