The main thing in the ability of metal detectors to catch the signal from the desired goal, in spite of all the obstacles , which are abundant in the real situation . To achieve this noble goal oriented at this time enormous power of scientific , engineering and manufacturing , and increase the capacity of which you contribute , the tender is not money for a small metal detectors modern . The amount of money is really a lot , the buyer does not hurt to understand the technology , such as multi-frequency BBS, FBS, MPS, DVT dual voltage , Double D.
Therefore, multi-frequency detection , using a wide range of frequencies , not just ignore the good mineralization , but also allow equally well to detect elements of small and large alike.
The fact that the high-frequency signal , for example, reveals a good 72KH small ( such as 2 mm ), but , unfortunately, not objects capable of penetrating deep into the soil at the surface and quickly damped . Low frequency signal , for example, 0.5 kHz , in contrast, penetrates deep into the soil , but remain small objects are not available to him .
Now with respect to mineralization and hot stones . Basically the same thing, only one other small and large . And about the same problems . We have a concept of the soil " mineral makeup . " It could be different . Soil can be magnetically saturated salt ( the beach) or some other factors . This all may be able to intervene conductivity , such as metals and significantly reduces the depth of penetration of the signal into the soil . Hot stones is the only stones that are able to express an opinion , good or nuggets such as coins because they have conductivity , like metals and usually has no value .
We must not underestimate these factors which greatly affect the ability of a metal detector , mineralization of soil was so great that the detection of a single frequency reaction almost every stone ( hot stones ) , and a good target . With all our efforts , we were unable to completely rebuild to detect a single frequency of " hot rocks " with a depth of detection . Does not exceed 5 cm coin detectors , made in technology FBS - Explorer , MPS - SD2200d Despite the low sensitivity by a third , but continued to work steadily on mineral soil so that does not respond to " hot rock "