Creating virtual textures with speed-invariant identities requires spatial constancy, attained by changing temporal frequency with a finger’s sliding speed. Implementing sensations of continuous frequency change, however, is non-trivial for low-cost wearable vibrotactile displays, as the amplitude of commonplace voice coil motors and linear resonant actuators varies strongly with driving frequency. In this paper, we present Pseudo-Frequency Modulation (PFM), a technique to continuously change the perceived frequency by modulating only the amplitudes of two single-frequency components in response to changes in sliding speed. Results of a psychophysical study with a wrist-worn vibrotactile display show that people perceive smooth changes in frequency with PFM, and this technique can be reliably used to display distinguishable textures which differ in terms of perceived surface properties such as coarseness.