DML Magnetic Locators

General Description		The DML2000 is a sophisticated, state-of-the-art locator that is highly reliable and user-friendly. It weighs just 1.6 pounds but is built rugged enough to operate under the most demanding field conditions. Four alkaline AA batteries provide up to100 hours of operation. There are only two controls and one switch, so it does not take long to become efficient using the locator. Just toggle the On/Off switch, adjust the Volume control for a comfortable signal level, and set the Sensitivity control to 3 (nominal setting). The separate Power, Volume and Sensitivity controls allow the operator to leave the Volume and Sensitivity controls in a favorite or preset position when the instrument is deactivated. Later when operation is resumed, these control settings remain unchanged.
Searching Low-Battery Indicator		When power is applied and there are no iron or steel objects in the immediate vicinity of the locator, you will hear a steady 20 Hz tone. As you walk the search pattern, slowly sweep the locator back and forth. The audio signal will remain constant until you begin to approach a target. The pitch (frequency) of the audio tone increases and peaks when the locator's tip is positioned directly over a target. You'll never have to be concerned about replacing batteries in the middle of a search operation. The Low-Battery LED indicator begins flashing when the remaining life of the batteries reaches 20 to 25 hours.
Magnetic Interference		The DML2000 is so sensitive that an operator's watch, steel arch supports, toe protectors or a pocket knife can cause magnetic interference and must be avoided while locating targets.
Theory of Operation All magnetic locators operate on the same basic principle; two fluxgate magnetometer sensors, securely mounted inside a rigid sensor support tube, measure the local magnetic field. The two-magnetometer sensors are vector sensors, mounted 20” apart and each measures the average magnetic field component along their sensitive axis, i.e. the magnetic field component along the longitudinal axis of the sensor tube. For a magnetic locator to work properly, the magnetometer sensors are aligned opposing so that the magnetic field measured by one sensor is the negative of the magnetic field measured by the other. The locator then sums the output of the two sensors. By summing the two output signals, you cancel any field common to both sensors, such as the Earth’s Magnetic Field, and leave only the differential magnetic field. The differential magnetic field, the magnetic field detected by one sensor and not the other, is the magnetic field of interest and hopefully represents the magnetic field of your target and not the field of your pocketknife, watch or the steel arch support in your shoes. The drawing on the right shows the construction of a typical magnetic locator and the location of the two sensing elements. *Field Operation* Good instrument performance goes hand-in-hand with proper operation. When searching for survey benchmarks or underground ferrous targets, the magnetic locator should be held in the vertical or near vertical position. In this position the instrument audio output is facing the operator and the controls are readily accessible. The picture at the top of this page shows how to hold the instrument for optimum operation. To pinpoint your target, rotate the instrument to the vertical and use and "X" or crossing pattern. The audio output will peak directly over your target. All Weather Operation The sensor housing is waterproof and the electronics water-resistant. Moreover, the circuit design and component selection ensures proper operation whether the ambient temperature is -20^oF or 120^oF. *Unparalleled Reliability* For added strength and reliability, the electronics package is made of impact resistant ABS plastic, while the sensor tube and base plate are made of 6061-T6 aluminum, welded together. Moreover, the two sensing elements are shock-mounted on there own individual support tube, inside the yellow sensor tube. This added sensor isolation guarantees that the sensor alignment and overall instrument performance will withstand normal physical abuse and harsh weather conditions. In addition, all electronic components have been carefully selected for long life and harsh environment operation. With normal handling, this combination of quality electronic components, shock-mounted sensors, and robust package design, should ensure a lifetime of maintenance free operation from your DML2000 magnetic locator.

All Weather Operation

Unparalleled Reliability