In 1902 he engineered the first commercial radiotelegraph link established in the United States by a U.S. company, connecting the island of Santa Catalina with the California mainland.

Inspired by reports of Guglielmo Marconi's accomplishments in developing radio communication (then known as "wireless telegraphy"), in the spring of 1897 he began conducting his own experiments.

In October 1901, he participated in that company's construction of temporary radiotelegraph stations that were used, with limited success, to report the results of the International Yacht races held in New York.

[4] Marriott was originally expected to build a radiotelegraph link between Denver and Golden, Colorado, which would have had little practical use beyond selling overpriced shares of stock.

However, he instead developed a plan to construct a link that would have actual commercial value, from the California mainland to Catalina Island, which was isolated because it lacked a telegraph cable connection.

In addition to regular commercial messages, the link was used to transmit content for a daily newspaper, known as The Wireless, which was published by the Los Angeles Times beginning on March 25, 1903.

[12] After his death in 1951, the IRE Board of Directors noted his passing with a resolution that stated: "His foresight in discerning the need for a society of radio engineers was a powerful stimulus to the formation of the Institute.