Some embodiments show a digital fault detection circuit with an input circuit comprising an input and at least one output, wherein a first signal state at the input causes a predetermined signal state at the output and a second signal state at the input leaves the output floating. The present invention improves upon the existing methods for amplifying padlock probes by eliminating or delaying the appearance of artifact products that cause false positive results, and also increase the sensitivity and speed of the assay. The spherical aberration is then corrected by using the amount of correction, which is defined as the final amount of spherical aberration correction, where the amplitude level of a tracking error signal obtained during this time reaches the maximum. The support base has a fastening frame fixed with the lower end of the main frame of a golf club cart.