d. Single-channel TACSAT, user-owned and operated, provides reliable, highly portable
communications. The system operates in the UHF band between 225 MHz and 400 MHz. Its terminal
use a UHF satellite system (fleet satellite and Air Force satellite). Unlike most communications
systems, single-channel TACSAT has no planning range. Its capacity to communicate depends on the
location of the satellite for LOS. The UHF frequency band used by TACSAT is out of the range of
other CNR systems, so interfacing is not possible.
Mobile subscriber equipment. MSE is being fielded to both active and reserve component Army
units. Located at corps and division, it was developed because of the need to modernize tactical
communications. MSE, as part of the ACUS, provides secure, automatic digitized voice, data, and
facsimile communications to both static and mobile users.
a. The MSE network at division can be described as a nodal switch system. Node centers
(NCs) are deployed from the division signal battalion to form a backbone network to provide geographic
and area coverage. The division signal battalion currently has the capability to deploy a maximum of
b. Large extension nodes (LEN) and small extension nodes (SEN) extend from the NCs to
provide units and CPs with access to the network. The headquarters of non-signal battalions are
provided wire access into the MSE network through a SEN switch (V2) and associated LOS radio
terminal (AN/TRC-190). The equipment and soldiers are from an extension platoon of an area signal
company within the division signal battalion.
c. Figure 1-1 shows an example of a division MSE network. Four NCs are deployed. The NCs
are symbolized by a triangle inside a circle. The SENs are symbolized by a circle with an X inside a
rectangle. The LENs are symbolized by a circle with two squares with an X inside the inner square.
d. Under MSE, users (not division signal battalion personnel) are responsible for installing and
operating the subscriber terminal equipment to the distribution boxes. The users connect their
subscriber cables and telephones to the J-1077 distribution boxes set up by the signal team. A call is
received at the SEN, where it is sent to an LOS radio by either radio link or cable. From the LOS radio,
the signal is transmitted to an NC and the routing process continues, sending the call to its destination.
Signal personnel must closely supervise and monitor the installation of the subscriber terminals,
whatever they may be (telephones, facsimile, and so forth), to ensure that the proper connections have
been made to obtain reliable communications over the MSE network.