00825cam a22002291 4500 war22000071 DLC 20260227112812.0 960530s1922 dcuaf f000 0 eng c war22000071 (OCoLC)34830249 Library, U.S. Army War College MoU DLC TK5707 .U6 no. 9 United States. Army. Signal Corps. Amplifiers and heterodynes ... Prepared in the Office of the chief signal officer, December, 1921. Heterodynes, Amplifiers and Washington, Govt. Print. Off., 1922. v, 38 p. plates, diagrs. 23 cm. Radio communication pamphlet no. 9 On verso of t.-p.: War department. Document no. 1092. Office of the Adjutant General. Radio. 92384 92384