VDI not reading correctly

[Neil in West Jersey]

As a coin gets deeper in the ground and approaches the fringe area of your coil field the VDI response will start to elevate. The response can even start wrapping to the negative side (-95,-94). This is normal behavior. You can even reproduce this effect to some degree in air testing. Mineralization strength, and lower sensitivity settings can cause this response to vary. I have Wheat pennies buried in a test garden that exhibit this behavior. For me Wheat pennies at an average depth of 5 to 8 inches come in from 83 to 87 on the VDI. Silver Dimes that are laying flat and unobstructed usually hit in the low 90's. I had 0ne start to wrap on me last hunt. It was down 8 inches. Correlate modes allow for easy adjusting to deal with this. If your ground VDI is in the -95 to -93 you are going to have a noisy hunt however.

Jack

Be careful with Correlate because you can end up ignoring those targets that don't match up right in the three frequencies. You may need to adjust the Span Limit and Wrap Limit.

For me here in Southern NJ, soil conditions tend to push VDI numbers down rather than up. Deep Wheaties are as low as 50, and some buttons read into the negative numbers. Coins sometimes will read higher once the soil above them is removed, leaving them at the bottom of an open hole.

 

[CyberSage]

Be careful with Correlate because you can end up ignoring those targets that don't match up right in the three frequencies. You may need to adjust the Span Limit and Wrap Limit.

For me here in Southern NJ, soil conditions tend to push VDI numbers down rather than up. Deep Wheaties are as low as 50, and some buttons read into the negative numbers. Coins sometimes will read higher once the soil above them is removed, leaving them at the bottom of an open hole.

Hello Neil,

The Correlate logic of the Vision/V3/V3i require only 2 of the three frequencies to agree within the span limit settings to elicit an audio response. The 7.5 Frequency usually plays the part of the middle man. The VDI reading will usually go up in an open hole. This is do the the filters dealing with the density change of the ground verses the open air of the hole. Think about what coins found close to the edge of a sidewalk or driveway sounds like. Copper/Bronze coin VDI responses sometimes drop in elevation as well. This is a good observation. This is usually do to a composite response from multiple targets. I have also noticed that Wheats with green deposits give off lower VDI's. I find a lot of these type finds in higher acidic soils around Spruce or Pine trees. My soil is moderate. I honestly don't have a clue how this behavior changes with mineralization strength. It sounds as though you have really good soil. This is great information. Thank you.

Jack