Chuck Edgar

Chuck Edgar (? – ?) worked in Tek's Sampling Group in the 1960s, led by Al Zimmerman.

He designed the trigger and sweep sections of the 1S1 and 1S2 sampling plug-ins for 500-series scopes.

In the 1980s he managed the Custom Modified Products team of the Terminals and Displays business unit of the Information Display Division.

Late 1950s

In the late 1950s, Chuck was a physics major at Reed College. While he was a student at Reed College, Nobel prize winner William Shockley came to Reed College to give a talk. Chuck picked him up from the airport in his car. Shockley simply seemed like a smart, pleasant fellow.

After leaving Reed College, he enlisted in the Army for a three year stint from 1955 through 1958. The Army Security Agency sent him to IBM for training in how to repair 80-column punch card system hardware. This training occurred in Endicott, NY and then Poughkeepsie, NY. Later, while stationed in Okinawa, he became an amateur radio (ham) operator.

After returning stateside from the Army, he got a bachelor's degree in Physics from Portland State University.

Early 1960s

Chuck Edgar started at Tek in 1960 as a summer intern in circuit design. Although his degree was in physics, he made use of the electronics knowledge he had gained as a ham.

Was hired by Norm Winningstad in 1960. While working at Tek, got an MSEE via Oregon State night classes taught at Tek. His master's thesis described a logarithmic sweep for a sampling system.

Chuck's first project at Tek was designing fixtures for diode and transistor rise-time measurements. This resulted in the 290, 291, and 292.

After the N plug-in, design work on the next sampling scope, the 661 and its plug-ins, the 4S1 and 5T1, started in late 1961. That was project led by Norm Winningstad where Chuck was a junior engineer.

After the 661, Al Zimmerman was Chuck's manager on at least one other project.

Mid 1960s

The 1S1, which was released in 1965, was designed by Gene Cowan (sampling and vertical) and Chuck Edgar (trigger, sweep, horizontal). It is a complete sampling system in a single plug-in. Part of the motivation for the 1S1 was to extend the life of the 500 series.

Almost immediately after the development of the 1S1, work began on the 1S2 project, managed by Al Zimmerman. There was a lot of industry excitement around TDR at the time and Tek wanted to develop a product quickly. Chuck Edgar designed the pulse generator and sweep. Gene Cowan designed the sampling and vertical sections. The little numerical readout was to save space on the front panel. Al Zimmerman figured out the switching for the numerical readout.

The mechanical engineer on 1S1 and 1S2 was skilled and surprisingly was trained as a chiropractor.

Most of the sampling instruments of the 1960s used tunnel diodes. Although it was not known at the time, the very fast tunnel diodes used in sampling gear are prone to failure (e.g., due to drift of characteristics such as peak current and peak-to-valley ratio).

1970s and 1980s

Chuck was transferred to Wilsonville and reported to John Bowne. At Wilsonville, Chuck managed a custom product group about 12 people, mostly engineers. Their work was mostly on computer displays and terminals.

At Tek, engineering managers were all trained as engineers.

Chuck left Tek in 1988 and got a job at Boeing. There, he worked on computer networking for 12 years and then retired.

Products by Chuck Edgar

Manufacturer	Model	Description	Designers	Introduced
Tektronix	1S1	1 GHz sampling system	Gene Cowan • Chuck Edgar	1965
Tektronix	1S2	Sampling system/TDR	Chuck Edgar • Gene Cowan	1967