Charles H. Vollum

Howard Vollum's revolutionary Type 511 oscilloscope had its roots in his teenage years in the 1930s, when he designed a primitive oscilloscope with newly commercialized cathode-ray tubes. This project helped him obtain admission to Reed College in Portland, Ore., where he built an oscilloscope that proved useful in testing audio amplifiers. in 1946, he co-founded Tektronix Inc. in Portland with M.J. Murdock. As the company's first president and chief engineer, Vollum directed Tektronix's focus on oscillography. The Type 511, also called the "Vollumscope," set a new standard for speed. Other developments followed, including the first direct-coupled high-gain oscilloscope; the Type 104 generator, the first to use square waves for transient testing of scopes; an oscilloscope plug-in unit that accepted interchangeable units; and ultimately, the design of the Tektronix cathode-ray tube.