TheCodeBreakers
Fallacy of key size, 407
Family codes, 283
Farago, L., 458
Federal Bureau of Investigation, 276, 286, 287, 372, 378
Federal Communications Commission, 34, 42
Feely, J. M., 436-437
Fellers, B. F., 250-254 passim
Fellgiebel, E., 232-233, 236-
237
Fenner, W., 235 Fernmeldeaufklarung, 238,
253-254 Field ciphers
origin of, 112-113,166
principles of, 126-127, 453-
454
Figl, A., 128, 227-231 passim Fingerprinting apparatus,
radio, 386 Finland, 258, 364 Finnegan, J., 310 "Fists" of radiotelegraphers,
31 Five-numeral system. See JN-
25 Five-Power Treaty, 176, 177,
181
Flag officers' system, 8,45, 301 Fleet Radio Unit, Pacific
Fleet. See FRUPAC Fletcher, F. J., 304 Foote, A., 368-369 Forschungsamt, 215, 224-226,
227, 228, 230, 232 Forschungsanstalt, 295-298 Fractionating ciphers, 121-122
See also ADFGVX France, 83-86, 101-104, 106, 110, 111, 172, 224, 260-261, 341, 395, 397, 398
See also Bureau de Chiffre;
Service du Chiffre Franz, W
annaabi.ee 
