TM 11-5805-715-34/EE119-DB-MMI-010/E154 CV3478/TO 31W2-2TTC39-12
Section II. DESCRIPTION AND DATA
1-7. Purpose and Use
signaling (dial pulse) and supervision used by the
The NATO Interface Unit (NIU) is a means to
AN/TTC-39 circuit switch to the NATO standard dc
connect national telecommunications systems
signaling. Conversion between the 4-wire system
which use different signaling techniques.
on the circuit switch side of the NIU and the 6-wire
cross- national connection, two NIU's are required,
system used on the NATO standard side is also
each of which accepts one national standard and
NIU described in this manual converts the 2600-Hz
Figure 1-2. Cross-National Connection.