DQL-16A Compass

Release Date:

2021-06-22

DQL-16A Compass

The DQL-16A compass is designed for azimuth measurement and features a liquid-damped compass dial. It is easy to use, with a robust aluminum housing that is impact-resistant, waterproof, and corrosion-proof. This high-quality, high-precision instrument delivers fast and accurate measurements and can be operated with one hand. The compass scale displays azimuth angles from 0° to 360°, with a graduation of 1°.

Feature Overview

Optical adjustment

Adjust the optics by rotating the eyepiece with your fingers until the scale lines are clear, and ensure that the slit of the azimuth compass eyepiece remains vertical.

Direction compass

Structure

This compass features a precision design, is quick and easy to use, and incorporates gem-bearing pivots and liquid damping to ensure smooth, vibration-free rotation of the dial.

Operation

With both eyes open, look through the eyepiece on one side of the compass and align the index line with the target. The main scale (large numerals) indicates your azimuth relative to the target, while the smaller numerals indicate the azimuth in the opposite direction—i.e., the target’s azimuth relative to you. This makes it easier to calculate an accurate azimuth.

Because viewing with only one eye can lead to latent strabismus, which may affect the accuracy of some individuals’ readings, we recommend using both eyes.

Please verify whether you have latent strabismus using the following method: View with both eyes, then close one eye (keeping the eye facing the eyepiece open). If there is no difference between the two views, this confirms that the axes of the two eyes are aligned, and you may then view with a single eye. If there is a difference, close the other eye and adjust your gaze so that you can still see part of the instrument; at this point, you should observe the reticle positioned above the instrument and directly aligned with the target.

This instrument can also be used for triangulation, as shown in Figure 2. Suppose that, according to the primary scale, the bearing to the small hill is 0°, while the bearing to the road bend is 64°; alternatively, on the opposite scale, these bearings are 180° and 244°. Your position is at the intersection of these two lines. If magnetic declination is taken into account, the result will be even more accurate.

The cotangent table on the back of this instrument can be used to calculate distance, particularly for determining position when two boundary markers separated by a small angle are visible. The calculation procedure is illustrated in Figure 2. Suppose the angle between the highway bend and the steel tower at the oilfield wellhead is 15°. Draw a line from the highway bend toward the oilfield wellhead steel tower that is perpendicular to the 64° bearing line; on the map, this distance is measured to be 1.6 km (1 mile). Therefore, along the 64° bearing line, your position is:

cot15° × 1.6 km = 6 km (cot15° × 1 mile = 3.7 miles)

Harbin Optical Instruments Factory Co., Ltd.

HARBIN OPTICAL INSTRUMENT FACTORY LTD.

Address: Jingwei Third Road, Daoli District, Harbin City 32 Number

Postal Code: 150010

Telephone: 400-030-0319 0451-84286338

Website: www.hrboptical.com

E-mail： hopt@hopt.cn