Abstract: A method for measuring harmonic load-pull including supplying a fundamental frequency signal to a frequency multiplication device under test and obtaining a target even-order multiplied frequency signal. The fundamental load impedance and an even-harmonic load impedance are independently controlled with a load mechanical tuner having an open-ended stub that is one-quarter wavelength long at the fundamental frequency and satisfies a short-circuit condition with respect to the fundamental signal. A fundamental source impedance and an even-harmonic source impedance of an input signal applied to the device under test are independently controlled with a source mechanical tuner having a short-circuit stub that is one-quarter wavelength long at the fundamental frequency and satisfies a short-circuit condition with respect to even-harmonics.