A device used to determine the mode of operation in a telegraph line.
Classification: Articles designed for connection to telegraphic or telephonic apparatus or instruments or to telegraphic or telephonic networks
NSN 5950-01-341-0767
NSN 5950-00-001-2621
NSN 6650-01-044-0183
NSN 6220-01-502-4396
NSN 5950-01-155-8026
NSN 5905-00-065-5413
NSN 5975-01-446-6074
NSN 6150-00-615-5886
NSN 5910-01-202-0571
NSN 6650-01-455-4327
NSN 6110-01-181-6216
NSN 5996-01-262-8953