The present article describes a transistor sampling oscilloscope which has an effective bandwidth greater than 1000 Me. The circuit of the oscilloscope mainly consists of sampling pulse generator

sampling gate and comparator. All the transistor employed are selected from normal drift divices. In this circuits) microwave crystal detectors is adopted for the sampling gate.The problem of generating sampling pulse by avalanche transistor and the technique of realizing wide bandwidth are given in some detail. The stability of sampling process is also analysed. Short pulses with rise time less than 0.5 millimicrosecond and pulse-modulated high frequency waves up to 1000 Me are observed with this sampling oscilloscope. Finally; further improvement on the electrical characteristics of this oscilloscope are discussed.