TY  - BOOK
ED  - United States.
TI  - Amplifiers and heterodynes ..
T2  - Radio communication pamphlet
AV  - TK5707 .U6 no. 9
PY  - 1922///
CY  - Washington
PB  - Govt. Print. Off.
KW  - Radio
N1  - On verso of t.-p.: War department. Document no. 1092. Office of the Adjutant General
ER  -