HELP ME!!! concentric 9" 3khz vs DD 7,5khz:blink:

[migleca]

Hello, I wonder which of these two coils will be the best for the detection of ancient coins in silver, copper, bronze. buttons and relics.
groundbalancing my soil varies between 36 and 42
please help me in choosing
miguel

 

[jmotycka]

I've read that if you are hunting areas without a lot of trash the 3KHz coil is the way to go, it's deeper and really sounds off when it detects silver and copper, I am wanting to buy one myself.

 

[Digger]

With your ground phase reading of 36 - 42 on your X-70 or X-705, mineralization should not an issue for any of the X-TERRA coils. As a general rule, larger coils detect large objects deeper than a similar designed small coil. Smaller coils are more sensitive to small targets and separate better than a larger coil of the same design. Lower frequencies are more sensitive to higher conductive targets such as silver and copper. Higher frequencies are more sensitive to lower conductive targets such as gold. DD coils separate targets better than a comparably sized concentric, based on the design of the detection field. Concentric coils will hunt deeper than a comparibly sized DD coil, if the soil conditions allow the use of concentric coils. And concentric coils will provide a more accurate TID than a comparibly sized DD coil of the same frequency. So without knowing how important target separation is at the sites you hunt, and based solely on the information you provided, the 3 kHz gets my vote! JMHO HH Randy

 

[migleca]

Thank you Digger, so you mean that with the coil 3khz I will not have problems detecting any kind of coins and relics
Thank you very much

 

[Digger]

Any of the three coil frequencies will find anything metal. Some just do certain things better than others. The 3 kHz coil is certainly the best for highly conductive non-ferrous targets, such as silver and copper. In addition, it is the best for discriminating ferrous from non-ferrous targets. This is because ferrous targets provide a more accurate composition analysis at lower frequencies. Higher frequencies are great for finding gold jewelry and very thin coins. But they don't discriminate out the ferrous targets very well. Especially large, irregular shaped ferrous targets because the eddy currents compete with the magnetic response to make it appear as a conductive target. As the frequency gets higher, (as with certain "gold" detectors) it becomes more difficult to determine whether large targets are ferrous or non-ferrous. JMHO HH Randy