An interesting site to visit is:

In the year 2000 my fiance and I visited her mother and stepfather, Mr. and Mrs. John P. Byrne (now both deceased), in Madison, Wisconsin. When Mr. Byrne found that I had been a radio broadcaster for 30 years, he excused himself for a moment, then he came back with a box containing an old radio and two sets of headphones, pictured below .

He explained that his father had built the old crystal set from a kit in 1920 or before, and he wanted to give it to someone who could appreciate it - and that someone was me. I gladly accepted it, brought it home and set it up for display in my bookcase where it has rested safely for the past seven years. 

I thought that the vintage radio should be shared with others so I decided to place its pictures on my Web site. It wasn't until today that I learned that the old radio has much more significance historically than I knew.

The story continues below:

I knew that the Byrne family had ties with the University of Wisconsin from many years ago. I was told that John's mother had once been a Professor there and I knew that John had received his education there.
As I began searching the Internet for information on the old crystal set, I came across an article about the early experimentation with broadcasting that was conducted by the University in the early 1900's. Only then did I realise the connection between the University of Wisconsin, radio station 9XM now WHA, John's father, and the old crystal radio.

"9XM Talking: The Early History of WHA Radio
by Randall Davidson, Wisconsin Public Radio

In 1914, Professor Edward Bennett of the electrical engineering department set up a wireless telegraphic set on campus and secured a license with the call sign 9XM. In June 1915, he arranged to transfer his license to the University of Wisconsin for use by the physics department for wireless experiments.

Physics professor Earle M. Terry was the driving force behind experiments at the UW. During this period, equipment was not available commercially, forcing Terry and his students to manufacture their own. For years, as part of the physics department, the radio station was near the University's glass-blowing laboratory, where the vacuum tubes for the radio station were made.

Terry, who passionately believed scientific advances should be put to practical use, considered operating 9XM on a regular schedule to transmit something that would be of use to all listeners. He eventually decided to send a dots-and-dashes version of the weather forecast."

"9XM Talking: The Early History of WHA Radio
by Randall Davidson, Wisconsin Public Radio
The first telegraphic broadcast of the weather forecast from the 9XM "studio" in the basement of Science Hall was at 11 a.m. on Monday, Dec. 4, 1916 (this can legitimately be cited as the first regular "broadcast" by the station that would become WHA). Few could receive it-at that time, there were only about 500 radio receivers in Wisconsin. However, those receiving the forecast were encouraged to transcribe it and post it somewhere in their community for others.

Experimentation with telephonic (sound) broadcasts continued, and it was sometime in early 1917 that Professor Terry invited friends to his home for what he termed the "first broadcast," a special transmission where records were played over the air. Unfortunately, his friends were unimpressed by the demonstration! Still, Terry persisted.

It was during a message with the Navy in February 1919 that 9XM made its first clear,
undistorted transmission of human speech. ...

Some documents indicate a regular weekly program of the phonograph records was
broadcast in early November 1920. ...

A regular program schedule was instituted on January 3, 1921, ...

The station continued to broadcast material telegraphically in addition to the voice broadcasts. ...

On January 13, 1922, the station was relicensed. The call letters WHA-which remain to
this day were assigned. The rest, as they say, is history."

A brief  history of this crystal catwhisker set.
So, now I know why John's father built the radio. He was an early listener to 9XM and WHA.
The headphones are "Murdock No. 55" and "C. Brandes, Superior Matched Tone" Pat. Pending.

Read the story of 9XM and WHA here:

I am WA4WRK Advanced. A Ham since 1962.