PROFESSIONAL DETECTION TECHNOLOGY
During field prospecting, operators encounter two critical diagnostic questions after registering an underground signal: first, determining the conductivity classification of the buried object (precious, ferrous scrap, or void), and second, pinpointing its exact physical epicenter before digging. In this article, we explain the technical distinction between Metal Discrimination and Target Center pinpointing based on official user manuals.
The essential distinction between Metal Discrimination and Target Center (Acoustic Analyzer) is the difference between signal classification and spatial pinpointing. The Metal Discrimination system analyzes electromagnetic return waveforms to classify buried anomalies into precious metals, ferrous scrap, or cavities, preventing wasted excavation. Conversely, the Target Center system operates as a zero-point acoustic pinpointer, utilizing rising audio frequency pulses and calibrated digital screen readouts (1 to 150+ for metals, negative numbers for voids) to isolate the exact physical epicenter before excavation begins.
Both systems complement each other in the field: Metal Discrimination tells you whether the anomaly is worth digging, while Target Center pinpointing directs you to the exact coordinates where excavation should take place, avoiding wasted effort and potential target damage.
• Operating Principle: The system emits and evaluates continuous pulsed electromagnetic responses through the sensor probe, measuring target conductivity shifts and phase angle variances.
• Operational Workflow per Manual: After locating the general target area, select Discrimination mode, hold the probe vertically 5 to 10 cm above the surface, press and hold the start button, and sweep steadily in a single direction over the target.
• Real-Time Graph Waveform Categories: The software generates immediate diagnostic waveforms categorized into three primary classes:
1. Precious Metal & Gold Waveform: Renders as a pronounced, high-amplitude positive waveform denoting high electromagnetic conductivity.
2. Non-Precious / Ferrous Waveform: Appears as a muted, low-amplitude wave characteristic of iron debris and discarded scrap.
3. Cavity & Void Waveform: Produces an inverted, negative downward dip in the graphic representing an air cavity or empty void.
• Operating Principle: Designated in user manuals as the Acoustic Analyzer, this system tracks electromagnetic field density, translating it into dynamic variable-frequency audio pulses and real-time numerical screen readouts.
• Operational Workflow per Manual: Upon activating the mode, the operator holds the scan trigger and executes a crosshair sweep (+) across both axes of the signal area, listening for rising audio pitch and watching the digital meter peak.
• Certified Numerical Diagnostic Scale per Official Manuals:
| Digital Screen Range | Signal Category in Manual | Associated Audio Response | Field Interpretation & Caveat |
|---|---|---|---|
| -150 and lower | Large subterranean cavities and open rooms | Low-frequency tone or specialized void silence | Substantial air chambers and structural voids |
| -101 to -150 | Medium open voids and cavities | Intermittent, spaced acoustic pulses | Diagnostic indication of underground cavity space |
| -1 to -100 | Minor air pockets or porous soil layers | Faint, irregular low-frequency pulse | Porous soil transition or small pocket |
| 1 to 100 | Non-precious / ferrous scrap metal signals | Choppy, low-frequency acoustic tone | Ferrous nails, wire, or surface iron scrap |
| 101 to 145 | Precious metal signals (silver, bronze, alloys) | Crisp, elevated pitch pulse intensifying in rate | Conductive metallic objects of exploration interest |
| 150 and above (150+) | Gold & high-conductivity metal signal class | Continuous peak audio pitch (high-frequency siren) | High-conductivity signal class; NOT a chemical guarantee of gold |
The official engineering manual clarifies that numerical readouts of 150+ indicate the target belongs to the high-conductivity electromagnetic signal category; it does NOT constitute chemical proof or an absolute guarantee that the target is pure gold. Digital values are influenced by target physical mass, purity, and host soil mineralization. The number reflects a signal classification scale, not guaranteed metallurgy.
The following breakdown demonstrates the distribution of Discrimination and Target Center systems across the four models:
| Model | Metal Discrimination | Target Center (Acoustic) | Total Systems | Official Price |
|---|---|---|---|---|
| GREAT 5000 | Included (3-way curve) | Included (Acoustic Pinpointer) | 5 Systems | $6,500 USD |
| GREAT 4-S | Included (3-way curve) | Not Included (focuses on Live Direct) | 4 Systems | $4,500 USD |
| GREAT 2-S | Included (3-way curve) | Included (Digital Acoustic Pinpointer) | 3 Systems | $3,500 USD |
| GREAT NEUTRON | Included (3-way curve) | Included (Integrated Acoustic Analyzer) | 3 Systems | $1,250 USD |
Exploration field practice recommends a structured 3-stage logical workflow for maximum accuracy and efficiency:
• Stage 1 (3D Survey): Run a 3D ground scan across the survey grid to identify subsurface electromagnetic anomalies, volumetric shape, and estimated depth.
• Stage 2 (Discrimination): Switch to Metal Discrimination mode over the anomaly coordinate to verify whether the waveform corresponds to precious metals, iron scrap, or a void.
• Stage 3 (Pinpointing): Activate the Target Center acoustic analyzer, perform a crosshair sweep (+), and isolate the peak frequency (150+ or audio siren) to fix ground zero before excavation.
Combines Discrimination, Target Center Acoustic Pinpointing, Live Streaming, and 3D Scan.
The ideal combination of 3D scanning, discrimination, and target center acoustic analysis at $3,500.
3 advanced systems including discrimination, acoustic pinpointing, and 3D survey at $1,250.
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