Master your AT Pro by starting with sensitivity level 8, then decreasing for stability while using frequency shift (F1-F4) to eliminate interference. You’ll choose between Standard’s three-tone system or Pro’s proportional audio, then customize notch patterns using ELIM to reject trash targets. Ground balance requires pumping your coil while holding GND BAL, with slight negative bias ideal for silver. Iron Audio transforms silent rejection into low-tone alerts, while pinpoint mode delivers precise target coordinates. The sections below detail each setting’s field-proven enhancement techniques.
Key Takeaways
- Six detection modes available: Standard for consistent audio, Pro for proportional responses, and Custom, Coins, Zero for specialized discrimination patterns.
- Sensitivity operates on eight levels; start at maximum level 8, then reduce to 6-7 for stability in trashy sites or interference.
- Ground balance affects depth and false signals; use automatic pumping method or manual adjustments with slight negative bias for silver targets.
- Iron discrimination scale 0-40 rejects ferrous targets; combine with twelve notch segments for precise custom acceptance patterns across conductivity spectrum.
- Frequency shift system (F1-F4) eliminates electromagnetic interference without depth loss; hold PINPOINT while pressing SENSITIVITY buttons to cycle frequencies.
Powering On, Off, and Factory Reset Procedures
Before you can detect anything, you’ll need to power up your Garrett AT Pro correctly. Press the mode button in the bottom left corner once—you’ll hear a confirming beep as the Target ID scale (0-99) illuminates. Your coil should rest flat on the ground, one inch above soil.
For power management, hold the mode button for one second to shut down. You’ll hear another beep confirming complete power-off, preventing battery drain.
Need to restore factory defaults? Hold that same mode button for five seconds. A double beep signals successful reset, wiping all customized sensitivity and discrimination settings while maintaining the six standard detection modes.
Your four AA batteries deliver 20-40 hours of operation—rotate the battery cover counterclockwise to access the holder when replacement’s needed. Remove batteries if you won’t be using the detector for an extended period to prevent corrosion inside the housing. The LCD battery life indicator displays four bars when batteries are fresh, dropping to one bar when replacement becomes necessary.
Understanding the Six Detection Modes
Your AT Pro offers six detection modes that fundamentally alter how the machine processes and reports targets.
Standard Mode delivers full-strength beeps ideal for straightforward coin shooting, while Pro Mode provides proportional audio with tone roll effects that reveal target size and shape nuances.
Standard Mode offers consistent audio for simple detecting, while Pro Mode uses proportional tones to reveal subtle target characteristics and size variations.
Custom Mode retains your preferred discrimination patterns and settings between power cycles, perfect for site-specific optimization.
The three core discrimination patterns available are:
- Custom – Saves personalized iron discrimination levels and parameters
- Coins – Optimized preset for high-conductivity targets
- Zero – Eliminates discrimination entirely for all-metal detection
Each mode generates distinct audio tone responses: low tones indicate iron, midtones signal gold and foil, while high tones identify silver.
Pro Mode renders these as variable-strength signals rather than consistent bell tones, enabling faster adjacent target recovery. The detector’s fast recovery speed is particularly effective in iron trash areas where multiple targets are closely positioned.
To activate the detector, press the mode button in the bottom left corner and tap it repeatedly to cycle through all six available modes.
Mastering Iron and Notch Discrimination Controls
The AT Pro’s iron discrimination operates on a 0-40 scale where each increment refines your ability to reject specific ferrous targets without silencing their presence entirely.
You’ll combine this adjustable threshold with manual notch placement through the ALM button, creating custom acceptance patterns that eliminate repetitive trash IDs while preserving adjacent conductivity ranges.
Iron Audio mode transforms discriminated targets from silent rejection into low-tone alerts, giving you critical context in debris-heavy sites where traditional all-or-nothing filtering risks masking valuable finds positioned near ferrous contamination. The midtone range adjusts from the discrimination point, ensuring you can differentiate between various target categories above your iron rejection threshold. The AT Pro provides twelve segments of discrimination, allowing you to modify rejection patterns with precision across the full conductivity spectrum.
Iron Discrimination Scale Explained
Understanding how iron discrimination interacts with the AT Pro’s conductivity scale will transform your ability to hunt trash-filled sites effectively.
The scale runs 1-40 for ferrous targets, while higher numbers toward 99 indicate conductive finds like silver. Your iron target identification skills improve when you recognize erratic cursor behavior—jumping between 30-35 signals iron, not treasure.
Conductivity scale interpretation becomes critical in these three scenarios:
- Setting rejection thresholds: Adjust iron disc from 0-40 using plus/minus buttons, with the two-digit LCD showing your current setting.
- Identifying masked targets: Iron audio lets you hear discriminated targets below your threshold while silencing trash above it.
- Avoiding over-discrimination: Set just enough rejection to eliminate common iron without blocking adjacent good targets.
You’ll maximize recovery speed in Pro mode while maintaining target separation through precise discrimination adjustments.
Customizing Notch Patterns Effectively
Two modification methods give you control: manually position the target identification cursor with NOTCH DISC (+/-) buttons and press ELIM to toggle each pixel, or press ELIM immediately when detecting unwanted targets mid-hunt for real-time rejection.
Your patterns persist in Standard and Pro modes through power cycles. The Custom mode retains your discrimination modifications even when the detector is powered off, ensuring your personalized settings are always ready for your next hunt.
For tolerance against varying target orientation, notch pixels flanking your desired item’s ID—a lost earring reads differently when standing versus flat, so bracket two positions either side for consistent detection. Coins mode excludes one pixel of foil and two pixels in the pull tab range, providing a preset pattern that eliminates common trash items while targeting valuable finds.
Audio Tone Response Settings
- Standard Mode Binary Response: Fixed-volume three-tone system delivers unambiguous ferrous/non-ferrous separation—your signal either fires or stays silent, eliminating proportional guesswork.
- Pro Mode Proportional Intelligence: Volume scales with signal strength while tone roll reveals conductivity shifts mid-sweep, exposing target shape and depth characteristics Standard Mode masks.
- Iron Audio Discrimination Bridge: Broken signals from discriminated iron suddenly produce clear, loud low tones, transforming masked trash into identifiable threats.
These audio tone advantages extend detection depth beyond Target ID range, letting you evaluate deep contacts through sound alone.
Optimizing Sensitivity Levels for Maximum Depth
The AT Pro’s eight sensitivity levels directly control detection depth, with levels 7-8 delivering maximum performance in low-interference environments but risking false signals in mineralized ground.
You’ll need to balance this trade-off manually—the detector offers no auto sensitivity option—by increasing levels until you encounter erratic behavior, then backing down one or two notches for stable operation.
In practice, you’ll lose only 0.5 inches on a dime dropping from level 8 to 6, but sensitivity reductions to level 5 cost you 1.5-2 inches of depth.
Choosing the Right Level
Eight sensitivity levels on your AT Pro directly control detection depth, but maxing out the setting doesn’t guarantee peak performance. Understanding sensitivity importance means balancing maximum depth against environmental interference—power lines, mineralized soil, and EMI all compromise your detector’s stability at level 8.
Effective adjustment strategies for best depth:
- Start high, reduce gradually: Begin at level 8, then decrease incrementally when you encounter erratic threshold or false signals until operation stabilizes.
- Leverage frequency switching: Hold PINPOINT and cycle through F1-F4 before lowering sensitivity—often eliminates interference without depth sacrifice.
- Accept minimal compromise: Air tests reveal dropping from level 8 to 6 costs only 0.5 inches on dimes, while level 5 loses 1.5-2 inches—making 6-7 ideal for trashy sites.
Run sensitivity three bars down in severe conditions while maintaining usable depth.
Balancing Depth vs. Stability
Pro Mode’s proportional audio lets you hear subtle target changes while maintaining control.
Remember: retained ground balance settings between sessions eliminate recalibration needs when hunting familiar territory.
Balance sensitivity against ground conditions for consistent target acquisition without compromise.
Audio Tone Settings and Iron Audio Features
When hunting with the AT Pro, understanding its audio tone system becomes critical for target identification before you dig. The detector delivers three distinct tones: low for ferrous junk, medium for small non-ferrous items like gold, and high bell-tones for coins and larger jewelry.
Your audio tone analysis improves dramatically in Pro Mode, where proportional volume reveals target depth and size while Tone Roll Audio exposes conductivity changes mid-sweep.
Iron audio benefits become apparent when you’re sorting through trashy sites:
- Discrimination Integration – Set discrimination at 30-35 with Iron Audio ON to hear ferrous targets as distinctive low tones rather than silence.
- Bottle Cap Detection – Pro Mode’s multiple tone response on iron helps identify masked junk.
- Extended Detection Range – Pro Mode audio depth exceeds Target ID depth, alerting you to deeply buried targets.
Ground Balance Techniques and Adjustments
Ground balance on the AT Pro directly determines whether you’ll detect targets at maximum depth or struggle against false signals from mineralized soil.
Understanding ground balance importance means recognizing when soil conditions demand recalibration—temperature shifts, mineralization changes, or moving between hunting zones all require attention.
For automatic adjustments, press and hold GND BAL while pumping your coil 2-20 cm above ground until LCD numbers stabilize.
Manual mode offers precision: press and release GND BAL, then use NOTCH DISC buttons to adjust based on audio response—decrease if tone’s high, increase if low.
You’ll maximize depth by biasing slightly negative for silver targets or reducing numbers for saltwater conditions.
Rebalance throughout your hunt as conditions shift. This guarantees you’re detecting targets, not fighting ground interference that limits your freedom to hunt effectively.
Frequency Shift Options to Minimize Interference
Electromagnetic interference transforms productive detecting sessions into frustrating battles against chatter and false signals, but the AT Pro’s four-frequency shift system gives you tactical control over operating conditions.
When electromagnetic chaos threatens your hunt, the AT Pro’s frequency shift technology delivers the tactical advantage you need to restore detection clarity.
Hold PINPOINT while pressing SENSITIVITY (+/-) buttons to cycle through F1-F4 settings displayed on your LCD. Your frequency selection strategy depends on identifying interference symptoms in real-time field conditions.
Systematic Frequency Optimization Protocol:
- Assess baseline noise by listening for chatter, erratic behavior, and signal distortion before target engagement.
- Cycle through all four frequencies to identify the quietest operating channel in your specific hunting location.
- Verify ground balance retention after frequency changes, then monitor audio stability across your entire detection area.
Power lines, nearby detectorists running EQUINOX or DEUS models, and mineralized soil all demand frequency adjustments for peak performance.
Pinpoint Function and Target ID Interpretation
After neutralizing electromagnetic interference through frequency optimization, you’ll maximize target recovery speed by mastering the AT Pro’s pinpoint function—a non-motion all-metal mode that transforms vague detection zones into precise digging coordinates.
Position your coil beside the target before activating to prevent tuning it out. Press the pinpoint button and sweep horizontally and vertically until audio peaks at maximum intensity—that’s your target’s exact center. The meter and variable sound signal work in tandem for pinpoint accuracy.
For target identification, consistent strong responses indicate solid targets beneath coil center, while broad signals from large objects require retuning to narrow the detection field. Both ferrous and non-ferrous items respond equally in this mode.
Always recheck excavated holes; multiple targets often occupy shared detection zones.
Frequently Asked Questions
Can I Save Custom Discrimination Patterns in Coins Mode Permanently?
No, you can’t save discrimination patterns permanently in Coins mode. Coincidentally, that’s exactly what Custom mode does—it retains your custom settings across power cycles. Switch to Custom to preserve your personalized discrimination patterns and maintain your detecting freedom.
What’s the Best Frequency Setting for Saltwater Beach Hunting?
You’ll find default frequency works best; shift to F1-F4 only when EMI causes chatter. For saltwater sensitivity, reduce settings to 5-8 bars and lower ground balance manually to 11 for ideal stability without frequency adjustment.
How Do I Adjust Threshold Volume on the at Pro?
Press the THRESH (+) or (-) buttons directly—no shift required. This threshold adjustment runs independently from volume control. Start at default level 7, then dial down until you’re barely hearing that background hum for maximum target detection freedom.
Will Ground Balance Settings Transfer Between Different Detection Modes?
Yes, your ground balance settings transfer between the AT Pro’s detection modes. When you switch from Standard to Pro Mode or Custom, the ground balance configuration you’ve set remains active across all modes without requiring recalibration.
What Target ID Numbers Indicate Silver Coins Versus Clad?
Silver coin identification lives in the VDI 93-99 sweet spot on your AT Pro, while clad coin differences show up lower at 89-92. You’ll break free from digging junk by discriminating below 93 for pure silver hunting.
References
- https://focusspeed.com/garrett-atpro-tips/
- https://www.youtube.com/watch?v=buxjNWjETSk
- https://www.youtube.com/watch?v=zWwfQn43F9A
- https://garrett.com/sites/default/files/2019-11/1533300_atpro_int_english.pdf
- https://www.youtube.com/watch?v=re8pd5se3c4
- https://metaldetectingforum.com/index.php
- https://www.treasurenet.com/threads/what-settings-do-you-use-with-the-at-pro.344192/
- https://seriousdetecting.com/blogs/detecting-prospecting/garrett-at-pro-metal-detector-manuals
- https://onpattison.com/news/2025/aug/28/how-to-use-garrett-at-pro/
- https://www.youtube.com/watch?v=kbUNMjBq0Cc
