Abstract We report on measurements with different configurations of transition radiation detectors, performed with electrons in the energy range between 0.75 GeV and 6 GeV. The radiator materials were foils of polyethylene or fibres of polypropylene or carbon. The multiwire proportional chambers for photon detection were operated with krypton, xenon or a mixture of xenon and argon. It is shown, that a very effective particle discrimination can be obtained from a rather simple detector configuration of moderate thickness, low weight and low cost. The method of charge integration is compared to the cluster counting technique.