We propose a new experiment to test absolute motion based on time of flight technique. A novel method is proposed to overcome the difficulty in time of flight experiments, namely the difficulty in measuring extremely small time intervals. Two light transponders are each fixed to the ends of a rigid rod. Each transponder consists of a light detector unit and a light emitting unit. The light detector unit, upon detecting a light pulse, triggers the light emitting unit. Let the transponder on one end of the rod be Transponder 1 and the transponder on the other end be Transponder 2. Transponder 1 is initially started and emits a short light pulse towards transponder 2. Up on detecting the light pulse, the detector of Transponder 2 immediately triggers the emitter of Transponder 2, which emits a short light pulse towards Transponder 1. Up on detecting the light pulse, the detector of Transponder 1 immediately triggers the emitter of Transponder 1, which emits a short light pulse towards Transponder 2 , and so on. The new technique involves a free running, continuous exchange of a short light pulse. The frequency of the pulses is determined by the round trip time of light. Absolute motion of the rod would change the round trip time, and hence the frequency of the pulses. Two such rods ( four transponders in total, two transponders on each rod) are used in the proposed experiment, with output pulse frequencies f1 and f2. The pulse trains from the two transponder pairs are applied to an electronic unit (consisting of mixers, filters, etc.) which detects the difference of the two frequencies: f1 — f2 . If absolute motion exists, then a difference frequency is detected when the orientation in space of one rod is changed with respect to the other rod. This experiment would provide practically unlimited accuracy in measuring absolute velocity.