The patterned interaction between synaptic inputs on the muscle fibers of crustacean claws has been found to be important in delineating claw behavior. When the excitatory and inhibitory neurons are fired at different frequencies in the opener muscle of the cutter claw of lobster Homarus Americanus, a complex pattern of postsynaptic potentials (PSPs) is observed. To analyze the nature of these varying patterns, an electrical equivalent circuit model of a single cell with two synapses, one excitatory and one inhibitory, is used. This model is implemented using a circuit simulation program. The PSP patterns generated by this model compare favorably with the patterns obtained from experiments. Thus the model can be used to formulate a theoretical basis for such pattern generation.