The paper describes a measurement of chaotic oscillations occurring in a base excited symmetrically bilinear oscillator. The details of the current experimental rig and possible modifications to improve the measurement accuracy are explained. The regions of chaotic motion predicted theoretically were confirmed by the experimental results arranged into bifurcation diagrams, which were obtained by numerical and experimental means. Clearance and modulus of the external force were used as branching parameters. The discussion of the system dynamics is based on bifurcation diagrams, Lissajous curves and power spectra. The investigated system tended to be periodic for large clearances and chaotic for small ones. This picture is repeated for the modulus variation, where periodic motion occurred for its small values and chaos dominated for larger forcing.