Teknetics Omega 8500 Metal Detector

Introduction

If you do not have prior experience with a metal detector, Teknetics strongly recommends the following:

1. Adjust Sensitivity: Set sensitivity to a low setting to avoid false signals. Always begin use at a reduced sensitivity level. High sensitivity may result in chatter or internal noise.
2. Outdoor Use Only: This detector is designed for outdoor use. Household appliances emit electromagnetic energy that can interfere with the detector. For indoor demonstrations, reduce sensitivity and keep the searchcoil away from appliances like computers, televisions, and microwave ovens. If the detector beeps erratically, turn off nearby appliances and lights. Keep the searchcoil away from metal objects like floors and walls.
3. Battery Type: Use only a 9-volt ALKALINE battery. Do not use Heavy Duty Batteries.

The detector is also available with an 11" DD coil (Item# OMEGA-11DD).

Terminology

The following terms are standard among detectorists:

• Elimination: Refers to a metal being "eliminated" so the detector does not emit a tone or light up an indicator when the object passes through the coil's detection field.
• Discrimination: The detector emits different tones for different types of metals, or "eliminates" certain metals. This feature allows users to ignore trash and undesirable objects.
• Relic: An object of interest due to its age or association with the past. Relics can be made of iron, bronze, or precious metals.
• Iron: A common, low-grade metal often undesirable in metal detecting applications (e.g., old cans, pipes, bolts, nails). However, some desired targets (property markers, certain relics) are made of iron.
• Ferrous: Metals made of, or containing, iron.
• Pinpointing: The process of finding the exact location of a buried object.
• Pull-Tabs: Discarded pull-tabs from beverage containers are common trash items. They can often be eliminated from detection, but some other valuable objects may have a similar magnetic signature.
• Ground Balance: The detector's ability to ignore or "see through" the earth's naturally occurring minerals, sounding a tone only when a metal object is detected. This detector uses proprietary circuitry to eliminate false signals from severe ground conditions.

Assembly

Adjusting the Armrest: The armrest can be moved forward or backward by removing a screw and nut and repositioning the 2-piece armrest. Shorter users may prefer the forward position. To move it backward, remove the plastic plug from the aluminum tube.

Armrest Strap (Optional Accessory): The strap is available separately and can help secure the detector against the arm when swinging vigorously. The detector can be used without the strap without compromising balance or stability.

Detector Components: The detector consists of the following main parts:

• Armrest
• Handgrip
• S-Rod
• Battery Compartment (located on the back side)
• 1/4" Headphone Jack
• Searchcoil Cable
• Middle Stem
• Lower Stem
• Biaxial Searchcoil
• Various locking collars, buttons, screws, bolts, washers, and Velcro straps for assembly.

Assembly Steps:

1. Position the S-Rod upright.
2. Rotate the LOCKING COLLAR fully counterclockwise.
3. Ensure the INTERNAL CAM LOCK inside the tube is flush.
4. Insert the MIDDLE STEM into the S-ROD with the SILVER BUTTON pointing upward.
5. Rotate the MIDDLE STEM until the SILVER BUTTON aligns with the hole.
6. Twist the LOCKING COLLAR clockwise until it locks.
7. Repeat steps 2-6 for the LOWER STEM.
8. Attach the SEARCHCOIL to the LOWER STEM using the BOLT and KNURLED KNOB.
9. Adjust the LOWER STEM length for a comfortable upright posture, with your arm relaxed and the searchcoil parallel to the ground.
10. Wind the CABLE securely around the STEMS.
11. Connect the CABLE PLUG to the housing. Ensure the Locking Ring is turned firmly to secure the connection.
12. Tighten both LOCKING COLLARS.

Note: An optional Extended Lower Stem (TUBE5X) is available for taller users.

Batteries

The detector requires a single 9-volt ALKALINE battery (not included). Do not use ordinary zinc carbon or "Heavy Duty" batteries. Rechargeable Nickel Metal Hydride batteries are recommended if using rechargeables.

The battery compartment is on the back side of the housing; slide the battery door to access it.

Battery Life: Expect 20-25 hours from a 9-volt alkaline battery (longer with headphones). Rechargeable batteries provide about 8 hours per charge. Backlight use significantly reduces battery life.

Speaker Volume & Battery Charge: Speaker volume may drop as battery life depletes. A flashing battery segment indicates low volume.

Battery Indicator: The battery icon shows remaining life. When it flashes, the detector will shut off within 10 minutes.

Battery Disposal & Recycling: Alkaline batteries can be disposed of in normal waste receptacles or recycled. Non-Alkaline batteries should be recycled. Check local municipalities for specific requirements.

Quick-Start Demonstration

Follow these steps for a quick demonstration:

I. Supplies Needed: Nail, Nickel, Zinc Penny (dated after 1982), Quarter.

II. Position the Detector: Place the detector on a table with the searchcoil hanging over the edge, or have someone hold it with the searchcoil off the ground. Keep the searchcoil away from walls, floors, and metal objects. Remove jewelry. Turn off interfering electronic devices. Pivot the searchcoil back.

III. Power On and Set Gain: Press and hold the [PIN POINT] button, then turn on the detector with the [GAIN] knob. Release [PIN POINT]. Set GAIN to the 12:00 position.

IV. Set Threshold: Turn the [THRESH] knob fully counterclockwise until it clicks.

V. Wave Objects: Wave each object over the searchcoil. Notice the different tones:

• Bass Tone: Nail
• Low Tone: Nickel and Zinc Penny
• High Tone: Quarter

Motion is required for detection.

VI. Adjust Discrimination: Press and release [MENU]. [DISC LVL] will activate. Press [ ] until "IRON" disappears from the screen, ensuring "FOIL" remains illuminated.

VII. Test Nail: Wave the nail over the searchcoil. It will not be detected, as it has been "discriminated out."

VIII. Further Discrimination: Press and release [MENU] once. Press [ ] until IRON, FOIL, NICKEL, P-TAB, S-CAP, and ZINC all disappear.

IX. Test Nickel: Wave the nickel over the searchcoil. It will not be detected.

X. Notch Nickel: Press and release [MENU] twice. [NOTCH] will activate. Press [ ] twice. The word "NICKEL" will flash and then become illuminated.

XI. Test Notched Nickel: Wave the nickel over the searchcoil. It is now detected, as it has been "notched in."

XII. All Metal Mode: Rotate the [THRESH] knob clockwise until a faint hum is heard. Pass a quarter over the searchcoil at varying distances to observe pitch and volume changes.

XIII. Pinpoint Mode: Press and hold [PIN POINT]. Motion is not required. A single audio tone is produced, regardless of metal type. The 2-digit display shows approximate depth in inches. Vary the distance of the quarter to observe depth display changes.

XIV. Return to Factory Default: Turn off the detector. Press and hold [PIN POINT] and turn the detector on. Release [PIN POINT]. The detector is now reset to factory default settings.

The Basics of Metal Detecting

A hobby metal detector is for locating buried metal objects, presenting challenges such as ignoring ground minerals, unwanted metal objects (like pull-tabs), identifying objects before digging, estimating size and depth, and eliminating electromagnetic interference (EMI).

1. Ground Minerals: Soils contain minerals that can interfere with metal signals. The detector can be "calibrated" using automated or manual ground-balancing features to eliminate false signals. The GROUND GRAB® feature helps maximize target identification accuracy and depth.

2. Trash: Undesirable items like aluminum foil, nails, and pull-tabs often induce lower tones and can be ignored using DISCRIMINATION features.

3. Identifying Buried Objects: In DISCRIMINATION Mode, different objects produce different tones and are classified on the display. A 3-digit numerical reading aids precise identification. This mode requires coil motion over the target.

4. Size and Depth of Buried Objects: The display shows relative depth and signal strength in DISCRIMINATION Mode. PINPOINT mode provides a more accurate depth reading in inches and allows for tracing the object's outline or exact location without motion.

5. EMI (Electromagnetic Interference): Electronic devices produce EMI that can cause false signals. The GAIN control can reduce susceptibility to EMI. If erratic behavior or "false" signals occur, adjust GAIN and THRESHOLD controls.

Headphone Jack: A 1/4" headphone jack is located on the left side. Connecting headphones disables the speaker and keeps dirt/moisture out with a rubber plug.

Using Headphones: Headphones improve detection of weak signals, extend battery life, and allow clearer hearing of subtle sound changes, especially in noisy environments. For safety, do not use headphones near traffic or other dangers. Use cables shorter than three meters.

Operation and Controls

Display and Controls: The Liquid Crystal Display (LCD) shows various indicators:

• Mineralization Readout
• Iron Indicator
• Signal Strength Bargraph
• Target Category Identifiers
• Overload Indicator
• Target Categories
• Ground Error window
• Auto Ground Offset
• [GAIN] Knob: Click right to turn ON. Turn clockwise to increase GAIN. Suggested setting below 70. Higher GAIN detects deeper and smaller targets but may increase noise.
• [GND GRAB] Touchpad: Press and hold for automatic Ground Balance.
• [PIN POINT] Touchpad: Press and hold to pinpoint target and view depth. Can be used for advanced options when in VOLUME or GROUND menu items.
• [DISC/AM/THRESH] Knob: Click left for Disc mode; click right for A/M (All Metal) mode. Turn knob to increase THRESHOLD setting.
• [MENU/QUICKSWITCH] Touchpad: Press and release to activate the menu and change menu items. Press and hold to momentarily change modes.
• [PLUS] and [MINUS] Keypads: Press once to modify active menu item; press and hold for continuous adjustment.

Control Knobs:

1. ON/OFF/GAIN: Click right to turn on, left to turn off. Clockwise rotation increases GAIN, allowing detection of deeper and smaller targets. GAIN values above 70 may introduce internal circuit noise. Operating "into the noise" (audible background noise) allows subtle changes in volume and tone to indicate buried metal.

2. DISC/AM/THRESH: Click clockwise to enter All Metal Mode (AM). This is the most sensitive mode and requires coil motion. In AM Mode, a hum's pitch and volume vary with target size and proximity. Turning the [THRESH] knob clockwise increases the threshold, allowing more signal. At zero threshold, the noise floor becomes audible. See "Deep and Threshold settings interaction" (page 15).

Separate Gain and Threshold Controls: GAIN affects signal amplitude; THRESHOLD sets the minimum signal strength for a response (hum level in AM Mode). Together, they control overall sensitivity.

Touchpad Controls:

GND GRAB: Ground Grab® Computerized Ground Balancing: Sets the detector's internal ground setting to match the ground phase. To use:

1. Locate a patch of metal-free soil.
2. Press and hold [GND GRAB], starting with the searchcoil 6" above the ground, then pumping it down to within 1" while keeping it level.
3. Watch the Ground Phase number on the display; it will stabilize when correctly measured.
4. Release [GND GRAB] to set the value.

Manual adjustment is available via the "GROUND" menu item. If the GROUND ERROR window flashes, refer to "Ground Grab Offset" (page 17).

PINPOINT: Press and hold [PIN POINT] to activate. Motion is not required. A motionless searchcoil over a target produces sound. The 2-digit number indicates target depth in inches (calibrated for coin-sized objects). This mode helps identify exact location, shape, and size for extraction.

Pinpoint Procedure:

1. Position the searchcoil just off the ground, to the side of the target.
2. Press and hold [PIN POINT].
3. Slowly move the searchcoil across the target to locate it by the loudest sound.

Narrow It Down: To refine location, slightly offset the searchcoil center from the target's center, release [PIN POINT], then press and hold again. Repeat as needed. Depth indication becomes less accurate after narrowing.

Operation and Controls (continued)

Pinpoint Retuning: To retune in Pinpoint Mode, release and immediately re-press the [PIN POINT] button. This helps narrow the response further.

MENU/QUICKSWITCH: This touchpad activates the menu and momentarily switches modes. Press and release to enter the menu; press and hold to switch modes (e.g., between ALL METAL and DISCRIMINATION).

PLUS and MINUS: Use [ ] and [ ] to modify active menu items. Press and release for single adjustments; press and hold for continuous adjustment.

Menu Items

DISC LVL: Discrimination Level: Adjustable from 0 to 80. Eliminates metal objects from detection. A setting of zero is not the same as All Metal. Higher discrimination levels may reduce sensitivity to small/deep objects and cause target category identifiers to disappear from the LCD.

NOTCH: Selective Target Inclusion or Exclusion: Functions only in DISCRIMINATION Mode. Allows changing the detection status of a target category. Notching a category can eliminate it or return it to active status. Categories that can be notched include Foil, Nickel, P-Tab, S-Cap, Zinc, Dime, Qtr. The NOTCH feature is not available in ALL METAL Mode.

VOLUME: Adjusts audio response from 0 to 10. Affects target volume, PINPOINT, alarms, and keypad beeps. Does not affect detector sensitivity.

NOTCH VOLUME: Adjustable Volume Offset by Target Category: In DISCRIMINATION Mode, allows independent volume adjustment for each target category. Range is 0 to -9. This is a negative offset from the Master Volume setting.

DEEP: Offers 4 settings with varying filters to increase depth under certain conditions:

• D0: Fast filter (target separation in heavy trash).
• D1: Regular filter (general conditions).
• D2: Deep filter plus 60 Hz notch (eliminates some EMI, increases noise floor; best in cleaner soils).
• D3: Deep filter plus 50 Hz notch (similar to D2).

Deep and Threshold Relationship: DEEP Mode settings can affect GAIN. Adjust THRESHOLD if needed. Momentarily press [PIN POINT] to reset internal offsets.

GROUND: Manually adjust the ground balance setting in ALL METAL Mode. Useful for fine-tuning after GROUND GRAB or for specific soil conditions (e.g., increasing setting in clean soil, decreasing in highly mineralized soil).

GROUND GRAB OFFSET: Available in ALL METAL Mode. Allows programming a positive or negative automatic Ground Grab offset. A blinking arrow indicator appears in the Ground Error section when an offset is programmed.

TONES: Variable Tone Selections: In DISCRIMINATION Mode, 5 pre-set tone variations are available. The d4 and d5 Tone options offer varied audio tones; d5 eliminates proportional audio for full response to small signals, enhancing deep target detection. In ALL METAL Mode, the TONES feature allows varying the pitch of the VCO tone via four frequencies (A1-A4).

FREQ: Frequency Shifting: If the detector chatters or is noisy when motionless, try shifting frequency to eliminate noise. Re-ground balance after changing frequency as it may affect it.

LIGHT: Adjustable Backlight: Levels 0 to 5. Higher intensity drains battery faster. Setting "0" turns backlight off.

NONVOLATILE MEMORY: Saves settings (except backlight and ground balance) when the detector is turned off. Backlight default is OFF, Ground Balance is 82.9.

RESET Function: Restores all original factory default settings. Access by turning off, then pressing and holding [PIN POINT] while turning on.

Factory Default Settings Table:

Ground Balancing

What is Ground Balancing? It's the process of canceling unwanted signals from ground minerals while still detecting metal objects. This is done by matching the detector's ground balance setting to the phase of the ground signal. Proper calibration results in deeper target detection, quieter operation, and more accurate identification.

How to Ground Balance:

1. Turn on detector, set GAIN to 12 o'clock.
2. Select All Metal Mode.
3. Adjust THRESHOLD for a slight background hum.
4. Find a metal-free patch of ground.
5. Press and hold [GND GRAB], pumping the searchcoil up and down (6" to 1") over the clean ground.
6. When the Ground Phase value stabilizes, release [GND GRAB].

A blinking arrow in the Ground Error window indicates a GROUND GRAB OFFSET is programmed.

Ground Data:

1. GND PHASE: Type of mineralization.
2. Fe3O4: Amount of mineralization (higher amounts reduce depth & ID accuracy).

Fe3O4 Bar Graph: A 4-segment graph indicating the amount of ground mineralization. It updates every second and is sensitive to motion. Metal or "hot rocks" cause inaccurate readings. The graph goes blank if motion stops. Magnetic susceptibility is expressed in micro-cgs units.

Ground Error: Located in the bottom left of the display, it indicates if ground balance needs adjustment. It compares the internal Ground Setting to the actual ground phase.

• Clear window: Detector is properly ground balanced.
• Bars at top: Internal Ground Setting is higher than actual ground phase.
• Bars at bottom: Internal Ground Setting is lower than actual ground phase.

If Ground Error exceeds three bars, adjustment is required.

Ground Adjustment Chart:

To minimize Ground Error, adjust the Ground Setting. Verify error by pumping the coil; adjust negatively if bars are at the top, positively if at the bottom.

In ALL METAL Mode, an out-of-adjustment Ground Setting produces audible differences in sound when pumping the coil.

Depth and Target Display

Reading the Display: The LCD shows probable target identification and depth. Consistent identification across sweeps suggests a repeatable signal. Inconsistent readings may indicate trash or oxidized metal.

Target Identification Accuracy: Highly accurate for described objects, but other metallic objects with similar signatures may register. Distance from the coil affects accuracy.

Target Categories on Scale:

• GOLD TARGETS: Middle or left-of-center. Flakes under iron; small items under foil/5¢; large items toward center.
• SILVER TARGETS: Right of scale, under DIME or QTR.
• IRON: Far-left side. Includes nails, historic iron relics.
• FOIL: Aluminum foil, gum wrappers, small broken pull tabs.
• NICKEL: Newer pull-tabs, many gold rings.
• P-TAB: Older pull tabs, medium gold rings.
• S-CAP: Older screw caps, large gold rings (class rings), some non-U.S. coins.
• ZINC: Medium conductivity objects, many non-U.S. coins.

Caution: Target indications are visual references; other metals may fall into categories. Accurate classification of ALL buried objects is impossible.

DEPTH INDICATOR: Calibrated for coin-sized objects, indicates probable depth in inches. "DEPTH" appears under the 2-digit number when using [PIN POINT].

TARGET-ID INDICATORS (TID): In DISCRIMINATION Mode, a 3-digit value helps identify targets. In ALL METAL Mode, it's a 2-digit number. Values vary based on object angle and distance. TID systems are separated for Discrimination and All Metal modes.

Multiple Target Category System: Available only in DISCRIMINATION Mode. Calculates four independent Target-IDs (one primary, three secondary) per coil pass. The primary ID correlates to the most reliable signal. Multiple illuminated categories may indicate noise, a weak signal, or an irregularly shaped target.

IRON INDICATOR: Illuminates promptly in the presence of iron. May blink rapidly if coil is swung too fast. In ALL METAL Mode, it fades over weak iron or heavily mineralized ground, and is solid over strong iron targets.

TARGET Readout Table:

Search Techniques (Motion modes)

Target Verification: After detecting a target:

1. Walk around the target in a circle.
2. Continue sweeping the searchcoil across the target.
3. Sweep every 30° or 40°.

If the tone and Target-ID value are consistent, confidence in identification is high. Changes may indicate multiple targets or irregular shapes. If the tone disappears at different angles, it may be trash or low-value metal. New users should dig all targets.

Coil Movement: Keep the coil level with the ground, about 1/2 inch from the surface. Do not swing it like a pendulum.

Pinpointing Process in Motion Modes:

1. Sweep over the target in a narrowing side-to-side pattern.
2. Note the spot where the "beep" occurs.
3. Rotate 90° to one side.
4. Sweep the same area at 90° to the first sweep pattern.
5. This pinpoints the target location with an "X".

Target Pinpointing (static search)

After identifying a target in motion mode, press and hold [PIN POINT] to find its exact location, shape, and size. The readout changes to show target depth in inches.

Pinpoint Procedure:

1. Position the searchcoil just off the ground, to the side of the target. Press and hold [PIN POINT].
2. Slowly move the searchcoil across the target to locate it by the loudest sound. The target is directly under where the sound is loudest.

Narrow It Down: To refine the location, slightly offset the searchcoil center, release [PIN POINT], then press and hold again. Repeat as needed. Depth indication is less accurate after narrowing.

Coil Drift: In PINPOINT Mode, drift can occur over time, affecting sensitivity. Periodic retuning (release and re-press [PIN POINT]) is required.

Treasure Hunter's Code of Ethics

• Always check Federal, State, County, and local laws before searching.
• Respect private property; do not enter without permission.
• Refill all holes and leave no damage.
• Remove and dispose of all trash and litter found.
• Appreciate and protect natural resources, wildlife, and private property.
• Act as an ambassador for the hobby with thoughtfulness, consideration, and courtesy.
• Never destroy historical or archaeological treasures.
• Conduct yourself with courtesy and consideration for others, as detectorists are judged by their example.

5-Year Limited Warranty

The Omega metal detector is warranted against defects in materials and workmanship for five years from the date of purchase to the original owner. Damage due to neglect, accidental damage, or misuse is not covered.

To Register: Register your warranty online for a chance to win a FREE DETECTOR at www.tekneticst2.com.

To Make a Claim: Proof of Purchase is required. Liability is limited to repair or replacement at Teknetics' option. Shipping cost to First Texas Products is the consumer's responsibility.

To Return for Service: Contact First Texas for a Return Authorization (RA) Number. Reference the RA number on your package and return the detector within 15 days of calling to:

First Texas Products L.L.C.
1465 Henry Brennan Dr.
El Paso, TX 79936
Phone: 915-633-8354

Note to Customers Outside the U.S.A.: Warranty may vary by country; check with your distributor. Warranty does not cover shipping costs.

FCC Compliance: This device complies with FCC Part 15 Subpart B Section 15.109 Class B. Changes not expressly approved by the responsible party could void the user's authority to operate the equipment.

Copyright © 2015 by First Texas Products, L.L.C. All rights reserved.

Published by First Texas Products, L.L.C.

Teknetics
1465 Henry Brennan • El Paso, TX 79936 • (915) 633-8354
MADE IN THE USA

Accessories

Teknetics® Padded Carrying Bag: Rugged nylon construction with an outside zip-pocket for batteries or small accessories (CBAG-T).

Teknetics® Camo Pouch: Camo pouch with two inside pockets, belt included (PCH-T).

Stereo Headphones: For true stereo sound, compatible with all Teknetics® models. Uses 1/4" and 1/8" jacks (HEADT).

Pinpointer: Pinpoints buried metal objects with audio and vibrator. Runs on one 9-Volt Battery (PINPOINTER).

Teknetics® Gold Pick: 10" tempered steel head, 3 1/4" wide edge. 19" overall length with fiberglass handle and rubberized grip. Includes a powerful magnet to discriminate iron and hot rocks (GOLDPICK).

Replacement/Accessory Searchcoils:

• 11" Biaxial Standard Coil (11COIL-TEK)
• 5" Biaxial Accessory Coil (5COIL-TEK)
• 10" Elliptical Concentric Coil (10COIL-TEK)
• 10" Biaxial Accessory Coil (10COILDD-TEK)

Coil Covers: Protect coils from abrasion and damage.

• 11" Biaxial Standard Coil Cover (COVER-11DD)
• 5" Biaxial Coil Cover (5COVER-CZ3)

Lesche Knife: High-quality tempered steel digging tool with a durable sheath. 12" length, 7" serrated blade (LESCHE KNIFE).

Teknetics® T-Shirt: 100% cotton with Teknetics® Logo. Available in S, M, LG, XL, XXL (TKTSHIRT).

Teknetics® Baseball Cap: One size fits all (TKCAP).

Neoprene Face Rain Cover: Protects from weather (FACE-COVER).

Gold Prospecting Kits: Available in Gold Kit, Deluxe Kit, and Hardrock Kit (PART NUMBERS: GOLDKIT1, GOLDKIT2, GOLDKIT3). Items include gold pans, classifier, vials, snuffer bottle, black sand magnet, treasure scoop, tweezers, magnifier, crevice tool, rock pick, instruction booklet, and backpack.

For complete details, visit www.tekneticst2.com or call 1-800-413-4131.