The J/V characteristics of a GaAs 0.24 μm channel length n+-n−-n+ diode have been measured at 8 K, 77 K and 300 K. Good agreement is observed with the J/V predictions recently reported by Awano et al. using a Monte-Carlo simulation of a similar device. This verifies the accuracy of their model, and substantiates their findings that electron transport in a 0.25 μm channel is near-ballistic at 77 K, with a peak ensemble-average electron velocity approaching 108 cm s−1 for an ensemble-average energy just under 0.36 eV. An effective time-average velocity of about half this value can be expected for the total channel transit.