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May 22, 2026 - 08:23 AM
The Double-D configuration in the INV28 coil uses two overlapping D-shaped windings that create a narrow detection field along the centerline, allowing the coil to isolate adjacent targets more effectively than concentric coils. In trashy sites where iron nails, pull-tabs, and foil cluster within a few inches, the DD field pattern reads each target separately rather than blending them into a single reject tone. This geometry also cancels ground mineralization more effectively, reducing false signals in saltwater sand and red clay soil. The DD design excels in mineralized soil and provides superior target separation, making it ideal for parks, beaches, and relic hunting sites with moderate trash levels. For more on how different coil technologies handle ground conditions, see our guide to metal detector technologies.
The Double-D configuration in the INV28 coil uses two overlapping D-shaped windings that create a narrow detection field along the centerline, allowing the coil to isolate adjacent targets more effectively than concentric configurations. In trashy sites where iron nails, pull-tabs, and foil cluster close together, this DD field pattern reads each target separately rather than blending them into a single reject tone. This geometry also cancels ground mineralization effectively, reducing false signals in saltwater sand. Check out our full selection of .metal detector search coils to see how upgrading your configuration changes your targeting dynamics.
The Double-D configuration in the INV28 coil uses two overlapping D-shaped windings that create a narrow detection field along the centerline, allowing the coil to isolate adjacent targets more effectively than concentric configurations. In trashy sites where iron nails, pull-tabs, and foil cluster close together, this DD field pattern reads each target separately rather than blending them into a single reject tone. This geometry also cancels ground mineralization effectively, reducing false signals in saltwater sand. Check out our full selection of .metal detector search coils to see how upgrading your configuration changes your targeting dynamics.
