Marconi Radiotrons Substitution List

This pamphlet was published by Marconi, the company responsible for patenting the radio in 1904. This specific pamphlet was a substitution list for replacement 'radio tubes'. Radio tubes generate and amplify radio-frequencies, but have a temporary shelf life and need to be replaced periodically. Before the introduction of television, and especially during wartime, having functional radios was crucial for any family.

Canadian Marconi Company, Tube Substitution List, (Montreal, n.d.)
Pamphlet. 29 pages.
Ley and Lois Smith War, Memory and Popular Culture Research Collection - The University of Western Ontario - London, Ontario
First World War