My first metal detector, Fisher F70, came with a 9-inch mono coil as standard. After about a month of active digging, I decided that I needed to study the technical part of the metal detector, and then I only learned the difference between mono coils and DD coils. Then I realized that I needed to buy a separate additional coil. I remembered about the mono reel only a couple of years later, when I decided to master the pit. And, already in trench conditions, a mono coil undoubtedly showed its need.
And yet, on numerous forums, thematic posts, on sellers’ websites and YouTubers’ blogs, I have repeatedly heard the same postulate. Which, it seems, or even exactly, but a mono coil with slow wiring gives a very good target detection depth. The coil works especially tenaciously on difficult soils and on small targets, such as chains or earrings. The general message of all these statements about the advantages of mono coils in depth was that due to the physical properties of a mono coil, the beam goes in a cone, allowing the device to see deeper even than with a large DD coil.
Why not try it yourself?
I made my first attempt to test and find out from personal experience whether a monocoil goes deeper than a DD coil three years ago. Then I discovered my first bag of scales, and quite successfully knocked it out in a plowed field for two days. When the plowing torch location was thoroughly cleared and passed with Nel Tornado. I swapped the reel for a monk and walked for about twenty minutes around the area, which had been pretty dug up over the previous two days. The test result is nothing. No new goals have been added. Although, in theory, it seems like it should be.
Years have passed.
Hundreds of hours of experience and as a result I came to the understanding that three years ago, I absolutely did not know the capabilities of my MD. I used the factory settings, whereas the device has a wide range of adjustments and settings for the required tasks. Including the detection of small targets at depth.
The beginning of spring this year. A friend comes to see me on the weekend; he has a jeep with a decent off-road capability, otherwise it would be a shame not to take advantage of the window of opportunity, so to speak. We are going to a forest village. The place is pretty damaged, but there is still the prospect of finding something, something that we missed earlier, always in our hobby. This happened then too. Literally fifteen meters from where we parked, I pick up the scales of Ivan the Terrible. Following me, a comrade is digging for exactly the same scales nearby. Wallet!!! And exactly. We dug the place for more than an hour and ended up digging up about thirty-five full-weight saber kopecks. Among Ivan there were also several coins of Tsar Boris.
When it became clear to both me and my friend that there was nothing more to catch in that patch, my friend moved on, and I decided to test the theory in practice. Moreover, such a good and illustrative example can turn out. I replaced the Tornado with a standard monk and began to comb out the area again, in the hope that a miracle would happen. But a miracle did not happen, although we managed to find one missed signal from a fragment of a cross. And that's all. The experiment had to be ended, a miracle did not happen. Although even here there remained the option of characterizing the area. The fact is that this place has not been plowed, and therefore the cultural layer is no deeper than a spade bayonet. All attempts to drill into promising places in this area were unsuccessful. So the question of the possible advantage of a mono coil in narrow areas for combing out knocked-out areas remains open. There is another place in mind for real testing, but there you have to wait until the fall until the crops are harvested. I think that based on the test at that place, I will make the final decision whether or not the monk sees deeper than the “steering wheel” of the DD. Ah, this will be interesting. So, dear readers, if you have not yet subscribed to our channel in Yandex Zen, be sure to subscribe.