TM (triode)
Development of the TM was initiated by colonel Gustave-Auguste Ferrié, chief of French long-distance military communications (Télégraphie Militaire).
[4][5] Ferrié and his closest associate Henri Abraham were well informed about American research in radio and vacuum technology.
Round were too unstable and unreliable for military service, and that Irving Langmuir's pliotron was too complex and expensive for mass production.
[6] Shortly after the outbreak of World War I, a former Telefunken employee returning from the United States briefed Ferrié on the progress made in Germany and delivered samples of the latest American triodes, but again none of them met the demands of the Army.
Their fourth prototype, which had vertically placed electrode assembly, was selected for mass production and was manufactured by Grammont from February to October of 1915.
[21] These were usually marked with a cross and suffered from unusually high noise levels and random early failures due to cracks in their glass envelopes.
[25] In 1916 British Thomson-Houston developed necessary technology and tooling, and Osram-Robertson (which would later merge into Marconi-Osram Valve) began large-scale production.
After the war, Philips launched production of the TM in the Netherlands as Type E.[19] Cylindrical construction patented by Peri and Biguet became a standard feature of British high-power tubes, all the way to the 800-Watt T7X.
[27] When the United States entered the war, annual output of the three largest American manufacturers could barely reach 80 thousand tubes of all types.
[2] This was too low for a fighting army; soon after deployment in France American Expeditionary Forces outran the quota and had to adopt French radio equipment.
[28] In 1923 Soviet authorities purchased French technology and tooling, and launched large-scale production at the Leningrad Electro-Vacuum Plant which would later merge into Svetlana.
[19] In the late 20th century, replicas of the TM were released at least twice, by Rudiger Waltz in Germany (1980s)[30] and by Ricardo Kron in Czech Republic (1992).
