IEEE Milestone to honor Walter Cady for first circuit controlling frequencies with quartz crystal resonator

January 2, 2020 | Contributed By - Sidney Lang, History Chair

The IEEE Board of Directors has approved the establishment of an IEEE Milestone in honor of the achievements of Walter Guyton Cady. The IEEE Milestones program honors significant technical achievements in all areas associated with the IEEE (see The creation of an IEEE Milestone is a lengthy and complicated process and only 206 have been established around the world. Sidney Lang, UFFC Historian, proposed and processed the application for the Cady Milestone.

Cady was a professor at Wesleyan University in Middletown, CT. In 1921 he developed the first circuit to control frequencies by means of a quartz crystal resonator. In his research, Professor Walter Guyton Cady made discoveries and studies that formed the basis of the fields of all three of the UFFC Society sections. Ultrasonics: Underwater ultrasonics (1917). Ferroelectrics: Piezoelectric effect in Rochelle salt (1937). Frequency control: Quartz resonator (1922). Historical information, publications, and photographs related to Professor Cady are found on the UFFC website at

The IEEE Milestone plaque will be dedicated at Wesleyan University in October 2020. It will contain the following text:

In 1921, research at Wesleyan led to development of the first circuit to control frequencies based on a quartz crystal resonator. This technique was later applied in standards of frequency, as a filter and for coupling between circuits. Piezoelectric quartz oscillators advanced ultrasonics, sonar, radar, and myriads of other electronic applications. They appeared in everyday life through quartz wristwatches.