AUTOMATIC GROUND TRACKING

Figure 1: Normal Searching vs. AGT

Figure 1 illustrates normal searching without AGT. Ground noises reduce the effective searching depth when moving from a previously ground-balanced area. The shaded area indicates ground that is not properly searched.

Diagram Description: Shows three figures searching. The top figure depicts "Position of ground balancing" and "Next ground balancing" with a depth indicator. The middle figure shows "Frequent ground balancing" with a "Reduction in unsearched volume". The bottom figure shows "Continuous searching".

Figure 2: Experienced Professional Searching

Figure 2 shows how a hardworking experienced professional avoids missing treasure by rebalancing their detector more often, which is very time-consuming.

Figure 3: Genuine Automatic Ground Tracking

Figure 3 demonstrates how genuine automatic ground tracking covers all the ground quickly and effectively. For this to occur, the detector must track quickly enough and not reduce in sensitivity.

Table of Contents

Klondike Instruction Manual: Version 1.0, November, 1992.

1. GENERAL DESCRIPTION
2. BASIC OPERATION
   1. Assembly Procedure
   2. Start-up Procedure in Basic Search Mode
   3. Headphone Socket
   4. Batteries
   5. Search Coil
3. EXPLANATION OF CONTROLS
   1. VOLUME Knob and On/Off
   2. SOIL Switch
   3. SENSITIVITY Knob
   4. SOUND Switch
   5. THRESHOLD Knob
   6. DISCRIMINATE Knob
4. GROUND NOISE REJECTION
   1. Automatic Ground Balancing (AGB)
   2. Automatic Ground Balance Tracking (AGB Tracking)
   3. Searching Modes
5. DETECTION TIPS
   1. General Operation
   2. Pinpointing an Object
   3. Recommended Technique
   4. Ground Noises
   5. Clay Domes
   6. Searching for Gold
6. PROPER CARE OF YOUR DETECTOR
7. WARRANTY AND SERVICE
8. SPECIFICATIONS

1. GENERAL DESCRIPTION

The Klondike builds upon the GT16000, offering faster response to ground variations, reduced ground noises, and increased coverage speed. Unlike older detectors that relied on manual ground balancing or fixed settings, often resulting in reduced depth and poor performance in highly mineralized ground, the Klondike utilizes a microprocessor for precise, rapid, and continuous automatic ground balancing. This technology empowers novice users with professional-level accuracy and allows experienced operators to cover more ground more effectively. Additional features include high sensitivity, superior ground noise rejection, rugged construction, a variable discriminator, and selectable audio output modes like the "Enhance" mode for detecting small objects. The detector can be configured for shaft or hip mount operation.

2. BASIC OPERATION

2.1 Assembly Procedure

Unpack the detector and verify the following parts are included: Instruction Manual, Warranty Card, Control Box, Main Shaft, Arm-rest, Search Coil assembly, Lower Shaft, and Bag. Retain the packing carton for future use. Fill out and mail the Warranty Card.

Figure 1: Klondike Assembly Diagram depicts the assembly components. Key parts include: 13 (Search Coil), 14 (Skid Plate), 9 (Isolator Rod), 11 (Tear-drop Washers), 12 (Nylon Nut), 10 (Nylon Bolt). Note that the search coil, skid plate, isolator rod, tear-drop washers, nylon nut, and nylon bolt are pre-assembled at the factory.

1. Slide the isolator rod (9) into the lower end of the lower shaft (8) until it clicks.
2. Remove the aluminium knurled nut (7) from the main shaft (2). Remove the friction ring (6) and tape from the Lower Shaft (8). Slide the aluminium knurled nut (7) and friction ring (6) onto the lower shaft (8). Slide the lower shaft assembly into the main shaft (2) to the desired length, ensuring the clip snaps into place.
3. Firmly tighten the aluminium knurled nut by hand to secure the lower shaft with the friction washer.
4. Slide the Arm-rest (1) over the back of the Main Shaft (2) until it clicks. Adjust forearm position by bending the fins.
5. Attach the Control Box (3) to the Main Shaft (2).
6. Wind the Cable (5) from the Search Coil (13) around the shaft, connecting the Cable plug (4) to the Control Box (3) socket. Heavy-duty insulating tape is recommended to secure the cable.
7. Install batteries (see Section 2.4).
8. High-quality headphones are recommended for serious searching. The loudspeaker is less sensitive and offers no ear protection from stray noises.
9. Hipmounting or strapmounting is achieved by placing the control box in its protective Bag, which can be threaded onto a belt or suspended. Secure excess cable to the shaft with tape. Moving cable can deteriorate electronically over time and produce noise.

2.2 Start-up Procedure in Basic Search Mode

This procedure ensures correct operation and setup for basic searching.

1. Confirm correct assembly (Section 2.1). Check all cables and connectors. Adjust the Arm-rest, Control Box, Lower Shaft, and Search Coil angle for comfort and proper operation.
2. Figure 2: Klondike Control Panel shows the layout of controls: Volume Knob (On/Off), Sensitivity Knob, Threshold Knob, Soil Switch (Normal/Difficult), Discriminate Knob (All Metal/Variable), Ground Balance Switch (Fix GB, Non-motion, Motion, Track GB), and Sound Switch (Boost, Normal, Enhance).
3. Set the Controls to the recommended levels: SOUND Switch: "Normal", GROUND BALANCE Switch: "Track GB, Motion", SOIL Switch: "Normal", DISCRIMINATE Knob: "All Metal", SENSITIVITY Knob: "To maximum".
4. Turn the detector on by rotating the Volume Knob clockwise to its maximum setting. The detector will start full operation after a few seconds.
5. Hold the Search Coil waist high, facing away from metallic objects. Adjust the Threshold Knob to a soft, comfortable audio level. Readjust the Volume Knob to a comfortable level when sensing a "large" metal object. The threshold may need readjustment.
6. To rapidly Ground Balance, hold the RESET switch in the "Up" position while raising and lowering the coil between 3 and 10 cm above the ground (Figure 4). Initially, a signal will be heard with coil movement. After a few moments, the sound will diminish until it almost vanishes, indicating automatic ground balancing. Release the RESET switch. If this step is skipped, the Klondike will still ground balance automatically after a few seconds.
7. The detector will now Automatically Track with the correct Ground Balance without loss of sensitivity as ground conditions change.

2.3 Headphone Socket

Located at the bottom right of the front panel. Use low impedance headphones (minimum 8 ohms) with a 1/4" jack (mono or stereo). Inserting headphones disconnects the loudspeaker. Headphones allow for a lower threshold setting, reduce distraction from outside noises, and conserve battery life. If headphones have a "Stereo/Mono" switch, set it to "Stereo".

2.4 Batteries

The detector requires eight (8) 1.5 volt AA (penlight) batteries. Alkaline batteries are recommended due to being sealed and less prone to leakage. Remove batteries if the detector will not be used for an extended period. Store batteries in a cool, dry place and dispose of them responsibly. The Klondike features an automatic "battery low" warning: a sharp "pip" sound at approximately 20-second intervals indicates about 15-20 minutes of useful life remaining. Alkaline batteries typically last 25-30 hours, carbon batteries up to 20 hours, and rechargeable NiCads over 6 hours (decreasing with cycles). Using headphones increases battery life. Always check battery "use by" dates.

Battery Replacement Procedure:

1. Turn the detector off.
2. Locate the battery compartment at the bottom of the Control Box. Press down on the end of the lid nearest the front panel and slide it out.
3. Carefully remove the two battery packs, taking care not to damage connecting wires.
4. Replace batteries with new ones, ensuring correct polarity as indicated by diagrams on the packs. Incorrect polarity will damage the detector.
5. Carefully replace the loaded battery packs and slide the lid shut until it clicks firmly into place.

Figure 3: Battery removal and installation illustrates the process of accessing and replacing batteries.

2.5 Search Coil

The Klondike operates exclusively with "SUPERSEARCH" coils manufactured by Minelab Electronics. The standard coil is eight inches in diameter. Optional coils include a six-inch and a twelve-inch elliptical coil. All "SUPERSEARCH" coils feature a "double D" configuration, offering advantages such as greater depth, wider search width, excellent performance in difficult soils, and ease of pin-pointing. A replaceable search coil cover is recommended to protect the housing from abrasion. The detector may emit a high-pitch "squeal" if it overloads, which can occur when sweeping the Sensing Head too close to a large object or very "hot" ground. In such cases, set the Soil Switch to "Difficult".

3. EXPLANATION OF CONTROLS

3.1 VOLUME Knob and On/Off

The detector is "off" when the knob is turned completely anti-clockwise. Turning the knob clockwise will feel a slight resistance and produce a click, indicating the "on" position. For best results with headphones, set the knob between half and maximum.

3.2 SOIL Switch

Set this toggle switch to "Normal" for good or clear ground. Select "Difficult" for ground highly concentrated in ironstone or mineralisation; this setting slightly reduces sensitivity. If variable responses persist, decrease sensitivity using the Sensitivity knob, which may reduce depth.

3.3 SENSITIVITY Knob

Turn the knob to its extreme clockwise setting for maximum sensitivity. This setting is recommended for most ground conditions. Adjust only in poor ground conditions (e.g., heavy mineralisation or ironstone), after first setting the Soil Switch to "Difficult".

3.4 SOUND Switch

Offers three alternative audio output sounds: "Normal", "Boost", and "Enhanced".

• "Normal": Detected signal increases loudness.
• "Boost": Amplifies the signal for extreme depth penetration in quiet or localized areas. May cause spurious noise in variable ground. Useful for pin-pointing faint signals.
• "Enhanced": Designed for detecting small and medium nuggets in highly variable ground. Alters response frequency, making the ear more sensitive to subtle changes. May be ineffective with excessive "hot rocks".

3.5 THRESHOLD Knob

Set this control to a slight turn past the point where the tone is just audible, avoiding an irritating level for prolonged use. In "Fix GB, Non-motion" mode, press the RESET Switch before setting the threshold.

3.6 DISCRIMINATE Knob

This is a useful aid for gold prospecting, provided its limitations are understood. Many experienced users recommend digging all detected objects. The discriminating mode does not sacrifice sensitivity or depth but may not discriminate at the full depth of an object. The discriminator is "off" or in "All metal" mode when the knob is turned fully anti-clockwise to the "off" position. It is disabled in "Fix GB, Non-motion" mode. Turning the knob clockwise to setting "1" activates Ferrous/Non-ferrous discrimination, with ferrous objects producing a staccato sound. Further clockwise rotation signals a greater variety of materials as non-targets. Experiment to find the best setting for your purpose. Increasing sweep speed improves discrimination depth. The discriminator automatically adjusts to ground interference for maximum reliable depth. In "mild" ground, discrimination is accurate at greater depths; in "hot" ground, depth is reduced. An audible "object" sound is always heard without loss of sensitivity. If the detector head is held stationary, discrimination sensitivity increases. On "hot" ground, false signals may appear initially but the detector will adjust. For "hot" ground, move the head near the object to "read" the ground before passing over the object. Repeatedly sweeping a ferrous object can cause false readings. Do not use the discriminator to test objects in holes or soil piles, as false signals are likely. It is most reliable on undisturbed ground. Overloading may occur with large surface objects, indicated by a high-pitch "chirp"; sweep further or set the Soil Switch to "Difficult". Experienced users recommend digging all detected objects, as discriminators may sometimes give no sound for valuable objects.

4. GROUND NOISE REJECTION

The Klondike excels at rejecting ground noises. Correct ground balance is essential to avoid missing valuable targets.

4.1 Automatic Ground Balancing (AGB)

The Ground Balance Switch has three positions: "Fix GB", "Non-motion", and "Motion" (including "Track GB"). The RESET Switch forces rapid ground balance at a specific spot, primarily used in "Motion" modes. Use AGB in "Motion" modes. In "Fix GB, Motion", AGB may need frequent repetition. "Track GB, Motion" is recommended for most searching. To perform AGB: set the detector to "GB Track" mode, hold the RESET Switch "Up", and raise/lower the Search Coil between 10 and 3 cm above the ground. The sound will diminish as the detector balances. Release the RESET Switch when the sound is minimal. If the soil is very hot and difficult to balance, raise the head about 20 cm and oscillate more slowly.

Figure 4: Automatic Ground Balancing (AGB) procedure illustrates the coil movement for ground balancing.

4.2 Automatic Ground Balance Tracking (AGB Tracking)

This mode is selected by setting the GROUND BALANCE Switch to "Track GB, Motion". The "Motion" aspect means a signal is heard only when the Search Coil moves relative to the detected object. Familiarity with the AGB procedure (Section 4.1) is required. In "Track GB, Motion" mode, the detector continuously adjusts its ground balance as ground characteristics change, minimizing spurious noises. This maintains effective detection depth, allowing for more accurate and rapid ground coverage. The ground balance setting averages the conditions of the recently covered ground, smoothing out ground noises and providing a sharper target signal. "Track GB, Motion" can be used without the RESET Switch, but use RESET if tracking appears slow due to sudden ground changes. Object sounds may temporarily inhibit AGB tracking. For highly variable ground, use "Track GB, Motion" with the SOUND Switch set to "Enhance".

4.3 Searching Modes

The Ground Balance Switch selects the search mode:

• "Track GB, Motion": Motion detector with automatic ground balancing and tracking. Recommended for most ground conditions.
• "Fix GB, Motion": Motion detector with fixed ground balance. Use the AGB procedure (Section 4.1) to re-balance. This is the conventional "motion" or "auto" mode.
• "Fix GB, Non-motion": Static detector with fixed ground balance. The signal is maintained when the Search Coil is stationary. Used for pin-pointing and searching small areas in hot ironstone. The discriminator is disabled in this mode. Ground balance cannot be set using only the RESET switch; switch to "Fix GB, Motion", press RESET, and follow procedure 4.1. If audio levels fluctuate, press the RESET switch.

5. DETECTION TIPS

5.1 General

The Klondike performs best when ground balanced approximately 2 cm (1 inch) above the ground, maintaining a constant height during sweeps. Practise maintaining consistent coil height to avoid confusing sounds and loss of depth.

Figure 5: Maintaining Search Coil parallel to ground shows correct and incorrect coil positioning during sweeps.

Familiarize yourself with the detector by digging all object noises to gain experience with audio signals and ground noises.

5.2 Pinpointing an Object

Sweep the Search Coil smoothly and evenly. Detect object noise from several directions, noting where the audio signals are strongest. For precise pinpointing with "double-D" coils, switch to "Fix GB, Non-motion" mode and reset the detector with the Sensing Head near the object. Pass the head slowly over the object, holding it at the maximum sound position. For loud sounds, flick the RESET switch as the detector approaches. Draw a line on the ground through the centre of the head in the direction of the shaft. Move 90 degrees, repeat the procedure to get a second line. The intersection of these lines provides an accurate pinpoint.

5.3 Recommended Technique

Scan an area with a broad, even sweep of the detector head, keeping it at a constant height (approx. 2-3 cm, depending on ground conditions and obstacles). Each sweep should slightly overlap the previous one; a slight overlap is sufficient due to the head's sensitivity across its full width.

Figure 7: Finding an object illustrates the process of excavating a target. After identifying a target's position, remove the top 3 or 4 cm of soil in a radius of approximately 14 cm, spreading the removed soil aside. Pass the coil over the flattened soil to detect small objects in the top layer. If not found, continue digging. Avoid sharp edges around the hole perimeter, as they can cause false readings. Proceed slowly to avoid losing the object or burying it deeper. Once the object is removed, lay the detector down near the hole with the coil on its side. Pass handfuls of soil over the coil to isolate the object, halving the material to narrow down the find. Note that this procedure may cause the detector to go off ground balance in "Track GB, Motion" mode. Check the hole for additional objects and always fill in dug holes.

5.4 Ground Noises

Ground noises can be confusing. Mineralised ground can produce responses similar to deep objects, with sounds that are broad, not loud, or crisp and sharp. Charcoal can sound loud and resemble metallic objects; experience helps operators read the ground. "Hot" rocks, rich in iron, produce strong audio signals. If unsure about a signal, switch the SOIL Switch to "Difficult" and reduce sensitivity. If the signal persists, it may indicate gold. "Negative" hot rocks or ground "holes" cause a reduction in sound; on recovery, the detector may give an audible signal that can be mistaken for an object. To check, switch to "Fix GB, Non-motion" mode and move the head slowly; a drop in sound intensity indicates no object. For a broad "positive" sound suspected to be mineralisation or a deep object, sweep the coil in a circular path around the sound source, then pass directly over the centre. Repeat with the coil at a right angle. If both passes yield a significant positive response, dig.

5.5 Clay Domes

Clay domes are regions of soil mineralisation that can produce broad sounds mistaken for deep nuggets. To differentiate, remove about 4 cm of soil in a 30 cm diameter circle. Attempt to ground balance the signal with the coil lowered into the hole. If ground balance is achieved, it is likely clay, as metal objects cannot be ground balanced this way. Metal objects produce a greatly enhanced signal when closer, unlike clay. Be cautious of spurious signals from shallow hole edges. This technique requires practice.

5.6 Searching for Gold

To find gold, search areas known for "coarse gold" (ranging from a grain of wheat to hundreds of grams). Nugget-bearing areas often result from broken-down gold reefs containing quartz and ironstone. Experienced prospectors learn to "read the ground" for signs of potential gold fields. Modern metal detectors significantly aid this process. The main challenge in many goldfields is the presence of heavy ironstone concentrations, which can interfere with detector signals. Some fields have been only superficially worked due to this interference.

6. PROPER CARE OF YOUR DETECTOR

The Klondike is a high-quality instrument requiring common-sense care:

1. Do not leave batteries in the Control Box for periods exceeding two weeks; leaking batteries can cause severe damage and void the warranty.
2. Avoid leaving the detector in direct sunlight or high temperatures. Cover it from direct sunlight and avoid storing it in a closed car trunk on a sunny day.
3. The Search Coil housing can wear through; use a replaceable skid plate and replace it before it wears out.
4. The Bag protects the Control Box from dust, mist, and rain, and cushions against knocks. Use the bag whenever possible.
5. The Control Box is water-resistant, not waterproof. Avoid unnecessary wetting. Keep it away from petrol or other oil-based liquids.
6. If the Search Coil is used in salt water, wash it immediately with fresh water.
7. Keep the unit dry and clean, avoiding sand and grit in shafts or tightening nuts. Do not use solvents; clean with a damp cloth and mild soap detergent.

7. WARRANTY AND SERVICE

The Klondike comes with a two-year parts and labour warranty, and the Search Coil is warranted for one year. Refer to your Warranty Card for details. Service can be obtained from the supplier or Minelab. This warranty is not transferable and is valid only if the enclosed warranty registration card is returned to Minelab Electronics Pty. Ltd. or an authorized distributor within 14 days of purchase. The warranty does not cover damage caused by accident, misuse, neglect, alteration, modifications, or unauthorized service. For specific warranty details, refer to the "Product Warranty Card".

8. SPECIFICATIONS (Klondike)

These specifications are subject to modification without notice.