View source for TT-21

==References==
* TM 11-2222 	Transmitter Distributors Teletype Model 14.  War Dept.  Aug. 1945.  126 p. 	U408.3.A13 TM 11-2222 Aug. 1945
* '''11-2222''' 	Receiving Transmitter Distributors [[TT-12]]/FGQ-1, [[TT-13]]/FGC-1 and Transmitter Distributor TT-21/FG, [[TT-25]]/FG [[TT-26]]/FG, [[TT-52]]/FG (Including Other Teletype Model 14 Transmitter Distributors).  Dept. of the Army.  May 29, 1951.  178 p. 	U408.3.A13 {{pdf|TM 11-2222 1951 NAVY-RADIO COM.pdf|TM 11-2222 May 1951}}