Difference In Coils

[Jnorthstar]

I was curious if anyone has any knowledge on this.I have a older model spectrum that came with a 9.5" coil and I found a 6" deep scan coil.What is the depth difference between the two under the same conditions.By the way I am mostly a coin shooter.Thanks in advance for any information.

[Steve Herschbach]

It depends on the ground conditions and the target. In air tests I would expect the large coil to do better on coin size targets, and on very small objects I would expect the small coil to do better. For neutral soil you can determine the difference yourself with simple air tests. That is your baseline. As ground mineralization increases the difference between a small coil and large coil changes. Large coils “see” more ground and as the mineralization increases the large coils are more impacted by the mineralization. I have seen ground where large coils have to have the sensitivity reduced so much that I was better off with the small coil even on coin size targets. For tiny targets a small coil is almost always superior.

Target/trash density also matters due to target masking, with small coils getting more “apparent depth” by being able to detect shallow targets a large coil misses entirely.

 

[Jnorthstar]

Thank you Steve.Just got my stuff ready going to try her out.