Walter Guyton Cady facts for kids

Walter Guyton Cady was an important American scientist. He was a physicist and an electrical engineer. He lived from 1874 to 1974. Cady was a leader in studying something called piezoelectricity. In 1921, he invented the first quartz crystal oscillator. This was a very important invention!

Early Life and Education

Walter Cady was born in Providence, Rhode Island. He went to Brown University and finished his studies there in 1895. Later, he studied at the University of Berlin in Germany. He earned his Ph.D. in Physics in 1900.

After his studies, Cady worked for the United States Coast and Geodetic Survey. He was a magnetic observer from 1900 to 1902. Then, from 1902 to 1946, he became a professor of physics. He taught at Wesleyan University. At Wesleyan, he was very interested in how electricity moves through gases. He also studied piezoelectricity, ultrasound, and crystal devices.

Discovering Crystal Power

Before World War I, Cady was researching radio detectors. But during the war, he started working with crystals. He helped the General Electric Company and the Navy. They were trying to find submarines using high-frequency sound. This sound was made using piezoelectricity.

In his early tests, he used crystals made of Rochelle salt. He noticed something amazing. A quartz crystal connected to an electronic device would vibrate strongly. But it only vibrated at one very specific frequency. At other frequencies, it would not vibrate at all. This gave him a brilliant idea! He realized these crystal vibrations could be used for radio.

Inventing the Quartz Oscillator

In 1921, Walter Cady designed the first circuit. This circuit used a quartz crystal to control frequencies. He received two important patents for his inventions in 1923. These patents were about how to use resonators in radio.

Cady quickly understood how useful these circuits were. They could be used as very accurate frequency standards. In 1922, he wrote a paper for the Institute of Radio Engineers about this. The next year, in 1923, he made history. He used his quartz resonators to compare frequency standards. He did this with scientists in Italy, France, England, and the United States. This was the first time such a direct international comparison was made! Cady later became the president of the Institute of Radio Engineers in 1932.

Contributions During World War II

During World War II, Cady again helped with military projects. He worked on how to use piezoelectricity for war efforts. For example, he helped create training tools for radar operators. These tools used piezoelectric devices in liquid tanks. They made realistic radar signals for practice.

Later Life and Legacy

Walter Cady retired in 1951. He moved to Pasadena, California. There, he continued his research at Caltech. In 1963, he moved back to Providence. Even after retiring, he worked as a consultant. He advised both companies and the government.

Cady held more than 50 patents. He invented the crystal-controlled oscillator. He also invented the very selective narrow-band crystal filter. He was a key thinker about ferroelectricity in crystals. He also wrote about the history of piezoelectric crystals.

He received many awards for his work. In 1928, he won the IEEE Morris N. Liebmann Memorial Award. In 1936, he received the Duddell Medal and Prize from the Physical Society of London. He also received honorary degrees from Brown University and Wesleyan University. His important papers are kept at the Smithsonian Institution. They are also at the Rhode Island Historical Society.