300MHz OSCILLOSCOPE.

A 300 MHz oscilloscope has been developed which allows the measurement of fast-rise signals as fast as 1 nanosecond. In this bandwidth, various distortions are caused by the signal reflection between the measured system and the oscilloscope, or that in the circuit of the oscilloscope itself. Therefore, the input impedance can be selected from either 1M OMEGA or 50 OMEGA independently. A bandwidth of 300 MHz and a risetime of 1. 16 nanoseconds are realized with an input circuit with a VSWR of 1. 20 or less. Unique design in trigger, sweep, and other circuits provides a high-speed response that supports the high performance of vertical amplifiers.