Picosecond pulse generator using delay lines

A passive circuit built with either high-quality coaxial cable of microstrip delay lines can convert a step signal with 25 ps rise time, from a conventional time-domain reflectometer, into a rectangular pulse of duration in the 50 ps-500 ns range, a separate delay line circuit being required for each pulse duration, The system provides an excellent probing signal for single rectangular pulse testing of analog pulse-shaping circuitry built to operate in the 2 Mb/s to 20 Gb/s range.<
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