Japón

a. vertical index button b. horizontal tangent screw c. automatic index button d. automatic tangent screw

MCI Course 0813B 2-32 Study Unit 2, Lesson 2 Exercise

Lesson 2 Exercise,

Answers The table below lists the answers to the exercise items. If you have any questions about these items, refer to the reference page.

Item number Answer Reference Page

1 a 2-18

2 c 2-21

3 b 2-25

Overview

Scope Distance measurement is a basic survey operation that you must be able to perform. In past survey missions, getting accurate measurements of distances on the ground had been a problem. Methods such as “chaining” and “taping” were both used to solve this problem. Both of these methods proved to be both time consuming and somewhat inaccurate. Today, field artillerymen use a more precise method known as electronic distance measuring with the DISTOMAT WILD DI 3000 Distomat.

In This Study Unit

This study unit contains the following lessons:

Topic See Page

DISTOMAT Wild DI 3000 3-3

MCI Course 0813B 3-2 Study Unit 3 (This page intentionally left blank.)

Introduction

Scope This lesson will introduce you to the distance measuring equipment DISTOMAT WILD DI 3000 (DI 3000).

Learning Objectives

After completing this lesson, you should be able to

• Identify the power source required to operate the DI 3000.

• Identify the appropriate prism to use when measuring distance.

• Identify the procedures required to set up the DI 3000.

In This Lesson This lesson contains the following topics:

Topic See Page

Introduction 3-3

Characteristics 3-4

Set Up the Reflector 3-6

Set Up the DI 3000 3-8

Lesson 1 Exercise 3-9

MCI Course 0813B 3-4 Study Unit 3, Lesson 1

Characteristics

Electronic Measuring

The DI 3000 is a timed pulse electronic distance-measuring (EDM) device. An EDM device measures the time needed for a pulse of infrared light to travel to the prism set and back to the EDM. The EDM then correlates that information into a distance. The measurement displayed by the EDM is the mean (average) of hundreds, possibly thousands, of pulses. As with all EDMs, range depends on atmospheric conditions; however, on an average day, ranges up to 6000 meters can be achieved with a single prism. You can attach the DI 3000 to both optical and electronic theodolites or you can use it as a stand-alone instrument. The illustration below shows a DI 3000 mounted in a T2-E theodolite.

Power Source The DI 3000 requires a 12V DC power source. It can run off a GEB 70 12V nickel-cadmium battery or 12V HMMWV vehicle power. The GEB 70 is good for about 1200 measurements. The illustration below shows a GEB 70 mounted on the leg of a tripod.

The battery has a nonconstant discharge rate. The battery will discharge quickly between power indicators 9 to 7 and 3 to 1. It will discharge slowly between indicators 7 to 3. The power indicators are displayed on the DI 3000 control panel. When the battery voltage drops below 11.0V (power indicator 1), the distomat will not measure a distance. Error message 12 appears on the display.

MCI Course 0813B 3-6 Study Unit 3, Lesson 1

Set Up the Reflector

Target Set The target set consisting of the reflector prism, the target carrier, and the tribrach is used in conjunction with the DI 3000. You will attach the target set to a GST-20 tripod and set the tripod up over the forward station. Level the tribrach and aim the reflector at the instrument on the occupied station. The illustration below shows a 3-prism target set.

Note: You will select the appropriate prism based on the distance to be measured and the atmospheric conditions.

Illustration The illustration below shows the three different reflector prisms that will be used with the DI 3000.

Reflector Set Ranges

The table below will help you determine which prism to use. Number of

Prisms

Atmospheric Conditions

Poor Average Excellent

1 3 11 About 2.0 km 2.3 km 2.7 km About 6 km 7 km 9 km About 9 km 11 km 14 km

• Poor conditions – strong haze with visibility about 3 km, or very bright sunlight with severe heat shimmer.

• Average conditions – light haze with visibility about 15 km, or moderate sunlight with light heat shimmer.

• Excellent conditions – overcast, no haze, visibility about 30 km, and no heat shimmer.

MCI Course 0813B 3-8 Study Unit 3, Lesson 1

Set Up the DI 3000

Procedures Set up a universal tripod and theodolite over the occupied station using the procedures outlined in Study Unit 2. Once you level and plumb the theodolite over the station, use the following procedures to attach the DI 3000:

Step Action

1 Take the carrying handle off of the T2-E by turning the carrying handle lock pin on the left side of the handle and by pulling the locking pin on the right side of the handle.

2 Attach the DI 3000 to the theodolite. Ensure the balancing springs are over the pin on the standard of the theodolite.

3 Press the two spring levers together.

4 Ensure that the DI 3000 is firmly seated directly on the adapter. 5 Release the spring levers to complete attachment.

6 Attach the battery to the tripod leg.

7 Slide the clip on the battery case over the bracket on the tripod leg and connect the battery.

8 To ensure the cable plug is inserted correctly into the socket, line up the red dot on the plug with the red dot on the socket and push the plug in.

Note: To remove the plug, hold the sleeve of the plug and pull. Do not twist.

Best Results To obtain the best results with the DI 3000, the infrared beam of the

instrument and the line of sight of the theodolite telescope must be parallel. The return signal will then be at its maximum strength. This is essential for accurate measurements and maximum range. The illustration below shows the parallelism.

Directions Complete exercise items 1 through 3 by performing the action required. Check your answers against those listed at the end of this lesson.

Item 1 The DI 3000 can run off of 12V vehicle power or