VT-4

various alphabet versions, seems to be called out in BC-86 first

• VT-4-A, WE-211A, Navy CW-1818
• VT-4-B, 211 Navy CG-1984 and CW-1818A (CG = General Electric Co.)
• VT-4-C, JAN 211 used in BC-191, BC-375 transmitters