Fisher GEMINI-3 warranty Tuning, Operating

TRACING

Tuning

1. Set the transmitter: Power: ON

2.Set the receiver: Power: ON Sensitivity: ZERO

3.Slowly increase the SENSITIVITY control until the audio signal is heard, then reduce SENSITIVITY until the audio just disappears. This is the point at which air coupling has been eliminated.

Operating

1.  Locate the buried pipe by circling the contact point, keeping the receiver in line with the contact at all times. Stay at least 30 feet from the transmitter.

2.  Once the pipe has been located by a sharp increase in audio and meter signals, the pipe may be traced exactly as described in the operating section of the Inductive trace instructions.

3.  Be aware that a nonconductive gasket in the pipe will terminate the RF signal from the transmitter.

Figure 9. Conductive Trace

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Gemini-3manual-.ind2 9

SEARCHING

Tuning

1. Set the transmitter:

                Power: ON

2.Set the Receiver: Power: ON Sensitivity: 7

   You should get a strong audio tone and meter indication at this point.

CAUTION: Never attempt to tune the GEMINI-3 in the presence of metal objects likes cars, metal walls, roofs or heavy metal reinforcements in any structure. Their presence will make proper balancing impossible.

3. Pick the unit up by the handle and balance it so that it is level with the ground and at normal carrying height (arm’s length). Five cm higher in the front is OK. For a deeper search, attach the fully lengthened carrying strap to the eyelets at the ends of the handle (see illustration on page 9). You will need to hold the instrument at this lower level while tuning if you plan to use it lowered. On some highly mineralized ground and some asphalt, you may not be able to use it with the strap fully lengthened. You will know this during tuning if you cannot reach a silence (null). Not reaching a null can also indicate the presence of nearby metal. If this is the case, move away from the metal to balance your GEMINI-3 to the ground only.

4.Still holding the GEMINI-3 parallel to the ground, slowly turn the BALANCE knob (with arrow) on the three- piece handle counterclockwise until you get silence (null) and zero meter reading. At this point there should be no sound as you rotate the knob 1/8- to 1/4-turn further counterclockwise before reaching sound and meter reading again.

5. If you cannot null the audio or your null point is less than

1/8 turn, reduce SENSITIVITY slightly and try again.

6. If you can turn the BALANCE knob more than 1/4 turn without an increase in the sound or meter, increase SENSITIVITY slightly and try again. Keep adjusting as described until 1/4 turn of silence (null) is achieved.

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6/13/06 2:52:52 PM