Features:Automatic and Manual Gain. The Rex receiver has the ability to operate in an automatic or manual gain mode. In the automatic gain mode, the sensitivity of the receiver is adjusted automatically, based on the strength of the detected signal, to produce a relatively constant and strong signal strength indication. In the manual gain mode, the user can adjust the sensitivity up or down to suit different locating scenarios.Directional Indication. The Rex receiver is equipped with directional indicators (arrows). These visual and audible indicators help the user locate the pipe or cable by showing which direction he/she should move in order to get closer to the target.Depth Measurement. The Rex receiver has the ability to measure the approximate depth of the target pipe or cable being traced. When a depth measurement is made, the receiver must be fully extended and the bottom tip of the receiver must be touching the ground. Depth measurements should only be made when the directional indication says that the target is close and the receiver's signal strength is maximized (peaked) over the target. Special considerations are required for the Sonde mode.Searching for a Sonde. Once in the surroundings of a sonde, it is important to differentiate whether you are positioned along the axis of the sonde (the direction of the pipe) or off to either side. In the sonde mode, the directional indication is not functional. Rotate the receiver back and forth and move in the direction that produces the maximum (peak) signal strength. As the receiver gets closer to the sonde, the signal strength increases and it will hit a peak when the receiver is directly over the sonde. Slowly rotate the receiver to fine-tune the peak signal strength, which will occur when the plane of the sensors is parallel to the axis of the sonde. For verification, rotate the receiver 90 degrees and see that it produces a "null" (signal strength very close to zero), and then counterrotate 90 degrees to go back to the original position. To measure depth, simply place the tip of the unit on the ground and press the DEPTH button when the signal strength is at a peak. The achievable depth depends on a number of factors, but typically it is possible to read depth up to 5 to 15 feet (1.5 to 4.2 m).Controls. The Rex Receiver controls are designed to be intuitive and require a minimum of training for effective use. The receiver can easily be operated with one hand.Visual and Audible Indicators. The information display areas for the receiver are easy to understand. In addition, the receiver has audible indicators to facilitate operation in heavy traffic or noisy areas. All visual indicators for the receiver are on the LCD display, which has six general areas to display information to the user: a Battery Indicator, a Gain Indicator, a Frequency/Mode Indicator, a Direction Indicator, an Alphanumeric Display and a Volume Indicator.Connectors and Accessories. The receiver has a standard 3.5mm headphone jack that accepts any mono or stereo earphones or headphones. The receiver automatically detects the insertion of the headphones or earphones and routes the audio signals to them, silencing the internal speaker. The receiver comes fitted with a rubber plug to protect it from water and dust ingress. It is recommended to keep the rubber plug inserted in the earphone jack when earphones are not being used. The receiver also comes standard with a belt holster for hands-free carrying. The receiver is shipped factory ready to detect sondes or other devices, such as inspection cameras, that transmit at 512 Hz.Battery Replacement. The Rex receiver is powered by one 9-volt alkaline disposable battery. The battery is located in the handle of the instrument and can be accessed by turning the screw counterclockwise. To remove the battery, simply tilt the unit so that the handle is pointing down, and the battery will slide out. When replacing the battery, look at the outside of the battery door for the proper battery orientation. As a safety measure, the unit will not turn on if the battery is not inserted correctly. You should never have to force the battery door closed. If the battery does not seem to be going in all the way, remove the battery, reverse its orientation and then replace it.Rex is recommended for locating all types of underground utilities: water and sewer, electric, telecom, and gas.