Moving to Chicago in 1904, he became an automobile salesman with the Franklin Auto Company and, as a publicity stunt, once drove a car up the steps of the General John Logan Memorial in Grant Park—with a photographer present and a policeman there to arrest him.

When the United States entered World War I in 1917, he enlisted in the Naval intelligence service and eventually became a lieutenant commander.

His commission came about as he understood the operation a device used in the Navy for recording radio and telephone conversations – the "telegraphone" – and the manufacturer was no longer in business.

[citation needed] Under the tradename "Z-nith", this partnership held a valuable Armstrong license but lacked funds for expansion to meet the demands of their order book.

[citation needed] During the Great Depression, Zenith employees took less pay and worked longer hours to keep the company alive.

[citation needed] At the same time McDonald launched a career as an explorer and adventurer that publicized the Zenith products and sent sales to new records.

[citation needed] As the economy improved, McDonald rewarded staff with additional shares in the company and a larger portion of its profits.

McDonald was well known for his charismatic leadership style, and his unexpected death in 1958 reportedly "left a void of talent at the top" of the company.

[6] One of the big obstacles to such a radio was that vacuum tubes in the 1930s and 1940s had trouble operating at higher frequencies using battery power supplies which were lower voltage than AC-operated designs.

Zenith Radio engineers Gustaffson, Passow, Striker and Emde came up with the model 7G605 "Clipper", that was approved by McDonald.

In December 1957, Eugene McDonald and Zenith engineers produced the world's first portable transistorized multiband radio, the Royal 1000 Trans-Oceanic.

The quality construction and engineering design efforts, a Zenith trademark were mechanically and electronically demonstrated in this model.

Zenith for the most part, until the end of the model line, used the latest cost-effective technology advances and materials in Trans-Oceanics.

For years it was the top selling "high-end" portable multiband radio until it was finally eclipsed by Sony with their digital tuning ICF-2001 and ICF2010 in the 1980s, which put the Trans-Oceanic out of business.

The next development was the "Flashmatic" (1955), designed by Eugene Polley, a wireless remote control that used a light beam to signal the TV (with a photosensitive pickup device) to change stations.