ATP-3-09-02 Field Artillery Survey Download
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Chapter 6 6-2 ATP 3-09.02 16 February 2016 Figure 6-1. Forward observer system (FOS) physical specifications—front view Handheld Terminal Unit Left Side 6-4. The left side of the HTU has seven ports and two binding posts. All ports are operational, but four ports will probably not be used for 13T FOS operations in the field (J3, J4, J5, and J7). The J2 port will be used only if an external alternating current (AC) or DC power source and adapter are used to power the HTU. The ports functions are briefly described below (see figure 6-2 on page 6-3): E1 and E2—dual binding posts used to establish single-channel communications using field wire. J1—dual channel modem port—used for connecting to one or two radios using a single or branched radio cable. It also can be used for other communication devices such as the Enhanced Position Location Reporting System. For Bradley fire support team vehicle operations, the J1 port will be used as the data connection to the Bradley FIST lightweight computer unit (LCU). J2—external power port—used for powering the HTU using 110/220V AC power or 28V DC vehicular battery. Both the AC and DC external power sources require special adapters and cables to convert the power for use by the HTU. J3—external keyboard or mouse—may not be used in the field, but is operational. J4—external video graphics array (VGA) monitor—may not be used in the field, but is operational. J5—RS-232 serial port (COM 1)—may not be used in the field but is operational. J6—parallel printer port—used to connect HTU to V2 LCU dot matrix printer (PN: 50786) using a new printer parallel cable. J7—RS-232 serial port (COM 2)—used for connecting the HTU to a ground/vehicular laser locator designator (G/VLLD) for 13F.