In one aspect, the present invention comprises a method for tuning a power line communication inductive signal coupling device comprising a coupler and a plurality of capacitors, the method comprising: passing a carrier frequency signal through the coupler; sensing an amplitude of the signal; and switching the capacitors until the amplitude of the signal reaches a maximum. In various embodiments: (a) the signal is transmitted by a second transmitter, and the method further comprises switching to a first transmitter for data transmission; (b) the signal is received by a receiver after passing through the coupler; and (c) the capacitors are switched by a relay controller receiving commands from a microprocessor.