Many types of parasitic oscillation are caused by small interelectrode capacitances (parasitic capacitance) or mutual inductance between adjacent wires or electronic components on the circuit board, which create an inadvertent feedback path. However these usually cause oscillations of high frequency, at the upper end of or above the passband of the equipment. This is because the phase shift of the small reactances in the feedback path, which increases with frequency, only become significant at high frequencies. Low frequency oscillations like motorboating indicate that some device or circuit with a large time constant is involved, such as the interstage coupling capacitors or transformers, or the filter capacitors and supply transformer winding.