The word "ham" as applied to Amateur Radio, dates back to 1908 and was the call letters of the first amateur wireless station operated by some members of the Harvard Wireless Club. They were: Albert S.Hyman, Bob Almy and Reggy Murray.

At first they called their station Hyman-Almy-Murray, but tapping out such a long name in code soon called for a revision. They changed their call sign to Hy-Al-Mu, using the first two letters of each name.

Early in 1909 some confusion resulted between signals from HyALMu and the Mexican ship named the Hyalmo. It was then the boys decided to use only the first letter of each name and the call became HAM.

In the early days of radio, amateur operators picked their own frequency and their own call letters. Then, as now, some amateurs had better signals than some commercial stations. The resulting confusion and interference finally came to the attention of Congressional committees, and they in turn gave much attention to proposed legislation designed to critically limit amateur activities.
In 1911 Albert Hyman chose the controversial wireless legislation bill as his thesis topic at Harvard. His instructor insisted that a copy be sent to Senator Davis A. Walsh, a member of one of the committees hearing the bill.

The Senator was so impressed he sent for Hyman to appear before the committee. He took the stand and described how the little amateur station was built. He almost cried when he told the crowded committee room that if the bill went through they would have to close the station. They could not afford the license fees and all other requirements that were set up in the bill. The debate started and the little ham became the symbol of all the little amateur stations in the country crying out to be saved from the menace and greed of the big commercial stations that didn't want them around.

Finally the bill got to the floor of Congress and every member talked about the poor little station HAM. That is how it all started. You will find the story in the Congressional Record. Nation wide publicity associated radio station HAM with amateurs. From that day to this, and probably to the end of time, in radio language an amateur is a ham.

(copied from the Sine of the Times - Indiana Co ARC)