In 1905 , the first U.S. advertisement for a radio receiver is published in the journal, Scientific American.
The ad was for a telegraph transmitter, priced at $8.50, from The Electro Importing Company, which imported specialized electronic equipment from Europe and helped to supply many of those who wanted to make their own radios and transmitters.
Learn more at http://web.mit.edu/m-i-t/science_fiction/jenkins/jenkins_3.html.