For a large crossbar resistor array recording information (i.e. changing the conductivity of each resistor) encounters difficulties caused by inability to address each resistor. When a voltage is applied to a target resistor, voltages are generated across many non-target resistors bringing about unwanted changes of their conductivity. To surpass these difficulties, the paper proposes a recording method in which the sum of two harmonic signals is applied to each resistor. Under certain conditions recording with coherent signals (i.e. signals whose frequencies are related as 2:1, 1:2, 3:2, 2:3) and recording with incoherent signals differ significantly: recording with coherent signals, unlike with incoherent ones, is phase dependent. Using simple resistor model-based analysis we show the possibility of recording arbitrary information (within certain limits) into a resistor array. The conditions securing the realizability and convenience of the two-frequency method are discussed.