Groundtech A2 Series 3D Ground Scanners & Metal Detectors

Groundtech A2 Series Overview

Every Groundtech A2 Series unit carries two instruments. The 3D ground scanner uses the MFS-3 dual gradiometer sensor with a plus or minus 2000 µT range, which Groundtech rates at up to 20 meters (66 ft), to map buried metal, magnetic objects and voids such as tunnels and rooms. The pulse-induction metal detector runs at a 500 Hz pulse frequency for searching and separating ferrous from non-ferrous metal in the upper soil layers, and Groundtech rates it at up to 1.5 meters (5 ft). Both models run on a 3.6 V 9.6 Ah lithium-ion battery that charges over USB Type-C with a 25 W adapter, rated up to 10 hours in the scanning modes and up to 6 hours in detector mode. A 240 MHz processor drives a built-in 480 x 320 pixel color screen, the unit saves 5 scans, and Groundtech gives a 2-year warranty.

Groundtech A2 vs A2 GEO: Which Should You Buy?

The A2 has six modes: 3D Ground Scan, Live Scan, Pinpointer, Detector Fast Scan, Detector Advanced Scan and 3D Detector Scan. The A2 GEO adds a third instrument, the geo-electric resistivity system, and two more modes, Resistivity Automatic Scan and Resistivity Manual Scan. Groundtech lists its output as 100 V DC, 66 mA at 62 Hz with a 50 sample interval, and says it detects groundwater, tunnels, tombs and caves from much deeper levels. The resistivity system scans across four lines. Groundtech gives no depth figure for the resistivity system, so we would not quote one.

Our recommendation: if your targets are metal, caches or relics, the plain A2 does that job, and the geo-electric kit adds cost, weight in the bag and setup time you will not use. Choose the A2 GEO when locating water or deep voids is part of the work, not a maybe.

Groundtech A2, Best For:

• Cache and relic hunters who want the deepest-rated Groundtech scan plus a PI detector
• Following a 3D scan with 3D Detector Scan mode on the same unit
• Working a marked spot with the detector without a second machine

Groundtech A2 GEO, Best For:

• Surveys where the question is groundwater, a cave, a tunnel or a chamber
• Comparing a resistivity survey with the magnetic scan of the same ground
• Professional and research users who need all three instruments in one case

Key Features in the Field

An A2 Series unit runs standalone: settings, modes and scan graphics show on the unit, so no phone is needed in the field. We recommend the small detector coil for tight or trashy spots and the large coil for covering open ground. Over Bluetooth 5 (LE), the G-Portal app for Android and iOS saves scans and shows them in 3D and 4D, with depth calculation and target shape; on the A2 GEO, G-Portal also handles the resistivity data. More modes also take more training, and we would plan time to learn each one before a paid or permitted survey.

Where the A2 Series Works Best and Its Limits

An A2 Series survey usually starts with the deep scan and narrows down from there. The 3D scan marks where something large or hollow sits, the pulse-induction detector checks the spot near the surface, and on an A2 GEO the resistivity lines come out when the question is water or a deep void. In our experience each system investigates a different physical property, and different soils, moisture levels and rock change the readings, so learn the site before deciding what an anomaly is.

Groundtech's scan depth rating is for the magnetic scan only and varies with soil structure, object size and scan function; large objects and voids are what reach it, small items do not. Groundtech publishes no waterproof rating for the A2 Series and rates it for use from minus 10 to 60 °C (14 to 140 °F). Our page on how deep metal detectors go puts the depth figures in context, and metal detector technologies explained covers how the pulse-induction side works.

A2 Series or GR-4 Series

The Groundtech GR-4 Series costs less and covers a lot of the same ground. The GR-4 DUAL also combines a 3D scanner and a pulse-induction detector with a built-in screen, with one PiD35 coil and the MFS-2 sensor, which Groundtech rates at up to 15 meters (49 ft). We would consider the A2 over the GR-4 DUAL for its wider set of scanning functions, but we would not call it better across the board without side by side testing. Pay for an A2 when the extra rated depth, the three coils and the headset matter to you. For a first scanner on a budget, the phone-based Groundtech GR-3 Series is the lowest-cost Groundtech scanner.

What Comes in the Box and What Fits

The A2 box holds the main unit with its built-in screen, the MFS-3 dual sensor, three detector coils (small 9.5 x 6.5 inch, medium 11.75 x 8 inch and large 14.5 x 10 inch), a headset, a charging adapter, a carrying bag and the user manual. The A2 GEO box adds the four conductive probes and four 25 meter (82 ft) conductor cables. For the last few inches of recovery, see Groundtech pinpointers.

Groundtech 3D Scanner Comparison

All six Groundtech scanners use a plus or minus 2000 µT gradiometer sensor and differ in rated depth, extra instruments, display and battery.

Our Groundtech buyer's guide compares the full Groundtech range. Survey work on any land needs the owner's permission; our metal detecting laws and ethics page is a starting point.

Why Buy the Groundtech A2 Series from Serious Detecting?

• Free Shipping on Orders Over $99: Your Groundtech A2 or A2 GEO ships at no extra cost across the continental US.
• Authorized Groundtech Dealer: Showroom in Ypsilanti, Michigan, full 2-year manufacturer warranty and product registration support.
• Help Before and After You Buy: Our staff answer setup, coil and A2 Series questions by phone or email.