Many of radio's earliest experimenters, drawn to the new and exciting technology, were teenagers or younger. Also, in the early days of radio, there was less standardization of technical terms. A sign in front of the spark transmitter operated by Newall A. Thompson, Jr. calls it the "Disperser", while Samuel Breck, Jr.'s receiver is labeled a "Responder".
 

Amateur Work, June, 1904, page 223:

"WIRELESS"  TELEGRAPH  PLANT  BY  AMATEUR  WORK  READERS
 
wireless makers     A wonderful piece of mechanism from the hands of schoolboys is that put on view recently in the Prince grammar school, Exeter and Newbury Sts. It is a wireless telegraph exhibit, and is the biggest surprise that has come to the management of Boston's schools during all the years that manual training has been a part of the system. The wireless plant is thoroughly equipped and is capable of being operated for eight miles. It is the work of Newall A. Thompson, Jr., 14 years old, of 553 Newbury st. west, and Samuel Breck, Jr., 13 years old, of 171 Bellevue st., Roxbury, both of whom are in grade 8. The boys last fall visited one of the fairs in Mechanics' Building and became interested in a wireless telegraph exhibit there. Being readers of AMATEUR WORK, and seeing the various articles on "Wireless Telegraphy" appearing in the different numbers, they determined to make an outfit themselves. In young Thompson's workshop the boys labored, and on Patriot's Day they were able to operate successfully for a distance of 256 feet. The experiments were carried further, and already they have demonstrated its practical ability by sending messages across the Charles river, which is not far from young Thompson's home. It has been found upon test that eight miles can be readily covered. Besides receiving parental advice and encouragement, both boys have been given much help by E. Bentley Young, master of the Prince school, and by the instructor in manual training, John C. Brodhead. The first receiver which the boys made was worked out under Mr. Brodhead. The apparatus was set up on the platform in the hall of the school. Visitors were greatly interested in the receiving and sending of messages.
    With the exception of one or two pieces of apparatus quite beyond their powers of construction at present, the work was done entirely by the boys.
disperser
responder