ATP-3-09-02 Field Artillery Survey Download
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Chapter 6 6-4 ATP 3-09.02 16 February 2016 Figure 6-3. Forward observer system (FOS) physical specifications—right side ENVIRONMENTAL SPECIFICATIONS 6-10. Some of the environmental specifications of the HTU are described below. (For more information see paragraph 1-12b in TB 11-7021-228-10-1). The operating temperature range: +25 to +120 degrees Fahrenheit. The original specifications from Litton state the range will be –25 to +120. However, subsequently it has been learned that from –15 to +20 degrees Fahrenheit, the screen becomes sluggish and may freeze up. Basic input/output system (BIOS) 1.22+ has been built to automatically turn on the HTU heaters when the temperature is below 25 to warm the HTU components to operating temperature. Storage nonoperating temperature range: < -40 and >150 degrees Fahrenheit. Altitude (operating): 15,000 feet. Altitude (nonoperating): 40,000 feet. Humidity (operating): 5 percent to 95 percent. Sand and dust: The HTU can withstand effects of 20 mph sand and dust for 30 minutes. Orientation: operates in any orientation. FUNCTIONAL SPECIFICATIONS 6-11. The functional specifications of the HTU are: Speed: 133 megahertz (MHz) (since the motherboard is a 25 MHz board, the HTU runs at approximately 75-100 MHz). Processor: AMD 5 x 86 central processing unit (CPU). Memory: 32 megabytes (MB) random access memory (RAM). Operating System (OS): SCO (Santa Cruz Operations) Unix V5.0.2 used when running the FOS software. Keyboard Backlight: Keyboard can be backlit in red and changed to a low/high setting. Display: 4-Color VGA liquid crystal display (LCD) monitor. Data Storage: 260, 340, or 520 MB internal PCMCIA Type III Hard Disk Drive (HDD). (Currently, the internal hard disk drive is 260MB.) Stores Unix OS, FOS software, and data entered by operator. Stores data automatically every 30 seconds—no operator action needed to save data.