A cardiac signal generator includes a portable housing, a memory, a processing device, a digital to analog converter, and at least one analog output. The memory stores programming instructions including instructions defining a plurality of mathematical relationships. The processing device is configured to execute the programming instructions to generate a sequence of output values using the plurality of mathematic relationships as a function of time, wherein the sequence of output values defines a sampled waveform output simulating an ECG signal and having linear portions and at least one curved portion. The processing device furthermore provides the sequence of output values at an output. The digital to analog converter is operably coupled to receive the sequence of output values from the output, and generates an electrical signal having a waveform corresponding to the sampled waveform output. The analog output is operably coupled to the digital to analog converter.