Abstract: A connecting cable comprising a length of coaxial cable having at one of its ends an input plug connector whose first and second input terminals are adapted to connect to the electrical output terminals of a pickup of a musical instrument, and means comprising a field effect transistor connected in the circuit of the cable and connector and housed within the connector.

Abstract: An electrical apparatus for determining the fundamental frequency of a musical note wherein the apparatus comprises a plurality of means for generating and responding to pulse type signals. More particularly, first and second means responsive to an electrical representation of the musical note are provided for generating first and second pulse trains whose pulses corresponding to the maxima and minima, respectively, of the electrical representation. The aforesaid first pulse train is applied to a first input of a first logic circuit means whose second input is fed a further pulse train from the output of a second logic circuit means.The second logic circuit means provides at its output either the second pulse train or a pulse train whose pulses are delayed relative to the pulses of the pulse train at the output of the first logic circuit means.