[. . . ] BATTERY TEST RECEIVER: When the receiver is first turned on, all of the information available on the LCD is displayed for approximately 3 seconds. A battery symbol in the upper right hand corner will show the approximate battery voltage is then displayed for about 2 seconds. With the receiver turned on, pushing the battery test button will show the approximate battery voltage and the battery symbol. If the batteries reach a low voltage during operation, this battery symbol will start flashing. [. . . ] When the transmitter is turned on, the TAP # window will show a self-test mode. If nothing is plugged into the output jack, the letter "A" will then appear on the numerical display. This indicates the transmitter is set up for Inductive Antenna Operation. With the direct output cable assembly or Inductive Coupler plugged into the direct output phone jack, the transmitter switches from the Inductive Antenna mode to the Conductive mode of operation. In the Automatic mode, the transmitter will match the output impedance and select the right tap that is needed for the best trace. In the Manual mode, the tap switch must be pushed until the tap # desired by the operator appears in the numerical display. Manual mode can also be used for mismatching the transmitter to the line being traced to correct for a broad peak reading. See page 8 DIRECT OUTPUT With the direct output cable assembly plugged into the transmitter, connect the red lead clip to the conductor being traced. Insert the ground rod in the earth and clip the black lead clip to it. This may be within inches of where the transmitter is connected, or several feet away. HINT: Pouring water on the ground rod can improve the ground connection in dry soil. At some point, the bar-graph will drop to a small value and then increase. Directional arrows are also present that will indicate what direction is needed to find the conductor. As the receiver moves past the null point, the directional arrow will change and a different tone will be heard. Each time the conductor is crossed, the directional arrow will change and the sound being heard will also change. The numerical signal strength meter will read absolute signal and it will be at a maximum number, even though the receiver is in the null mode of operation. In the Automatic Null Mode, the receiver will provide direction to the conductor with left/right arrows on the display so the receiver must be at right angles to the conductor path in the Auto Mode. LOCATING BY THE NULL METHOD - IN THE MANUAL MODE Locating in the manual mode allows the operator to take control of the receiver sensitivity. The large knob that was the loudness control in the auto mode is now the sensitivity control. Change the receiver to Manual and push the Null switch for Null operation. A flag will point to the word NULL on the lower left corner of the LCD display. In the upper left corner of the display, a numerical read out will appear. [. . . ] Reducing the signal on the line being traced can be accomplished by setting the transmitter to Manual Mode and the tap switch to number 4 or 5. This will be the wrong impedance tap for a long or deep trace, but the reduced signal will un-flood the receiver and a sharp crisp peak reading can be found near the transmitter. 8 Figure 8 DETERMINING DEPTH The Digi-7 can be used in several ways to locate the depth, however the Manual Mode - NULL is the easiest to use. The null or peak method can be used, but in the peak mode the position of the receiving antenna is more critical and this is not the case in the null mode. There is a bubble level to the left of the receiver's NULLPEAK switch. [. . . ]