When the U.S. entered the war in 1917, it was unprepared for the type of warfare it encountered. The concept of spending days or weeks in a 'trench' was not our way of fighting. The British, French and other allies, however, had been at it for several years by that time and had developed a large number of field proven radio devices suited to that environment. America's only near term hope of producing large quantities of acceptable devices to support our troops would be to copy, with minor modifications, this field proven equipment. In the meantime, the AEF would use the existing 'foreign' equipment.
Several AEF "Radio Apparatus Descriptive Bulletins" from very early 1918. The Americans would have to rely on this equipment until sufficient quantities of U.S. made equipment was on hand. It is probably safe to say that due to the speed with which the war was fought and won, large amounts of U.S. made equipment did not arrive in time to be used.
It is easy to visualize a biplane, circling slowly over an enemy position, transmitting not only the effectiveness of shell fire and sending corrections to the artillery battalions, but also reporting enemy troop strength and movements. This test report, by Armstrong, gives an interesting picture of the current state of the very important 'trench' type receivers.
