Written by the TreasureGuide for the exclusive use of Treasure Beaches Report.
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| Gold Ducat Found With Hundreds of Other Coins. Source: See English.radio link below. |
Hundreds of gold and silver coins were found by a couple walking through a woods.
“As they were walking through the forest, they spotted a few coins, two made of gold and one of silver, lying on the ground. They were probably dug up by some forest animals, most likely by wild pigs.
“There was a large stone protruding from the ground. When they pulled it out, they saw a large amount of gold and silver coins underneath and they immediately called us to announce the discovery.”
Among the coins are gold ducats bearing the image of the Czech King and Holy Roman Emperor Charles IV, Albrecht of Austria and Rupert of the Palatinate as well as ducats from the Hanseatic city of Lübeck...
Here is the link for the rest of the article.
https://english.radio.cz/valuable-14th-century-coins-found-couple-walking-west-bohemia-8688913
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Last week I talked about hunting a couple days right after tropical storm Esaias passed us. By the second or third day there were very few targets left after every inch of the beach had seemingly been detected multiple times by all the detectorists that were out after the storm. Nevertheless I found a line of very weak signals that that ran along a thick layer of buried shells. The signals were easy to miss, but they were there.
In situations like that, it takes a slightly different approach to find the few good signals. When signals are very weak, they easily can be mistaken for noise caused by ground mineralization or other kinds of sources, so the task is to discriminate between the noise, or false signals, and the good but weak signals.
Detectorists are very familiar with some types of noise. There can be static caused by power lines, buried cables, lightning or even faulty detector wiring or insulation. Other external sources of noise might include ground mineralization, including noise caused by salt mineralization or black sand. Wind and a high surf also causes background noise that can make it more difficult to hear weaker signals.
Besides all the possible sources of external noise like those just mentioned, there is also internal noise. Some noise is caused by the sensory system of the detectorist, and other internal noise arises in the central nervous system. If you have ringing in the ears (tinnitus), that can make it difficult to identify detector signals in a particular range of frequencies. You can also be distracted or simply lose focus and miss good signals. Junk can mask good targets, but it can also be distracting. Any time one thing catches your attention it takes your attention away from something else.
I recently recommended taking time to tune your detector before beginning hunting. You might not think it is necessary every time, but it can help - especially when there are few signals or you just want to focus on the weak signals that can easily be missed or passed over. But, of course, you can also continue to make adjustments as you detect.
You might think that when you tune your metal detector you are adjusting the detector to the environment, but there is more to it than that. When you tune your detector, you are also adjusting your detector to yourself. To use signal detection terminology, that means taking into account the ROC (receiver operating characteristics). That involves adjusting for internal sources of noise as well as external. It means taking into account the unique qualities of your sensory system and how you process information, as well as the various types of noise in the external environment.
Some people can hear better than others. Most people lose some hearing as they get older. Hearing loss can be more pronounced in certain frequency ranges. My wife, for example, will not hear the higher frequency chirps of a red bird that I can clearly hear. I'm not suggesting that she is older than I - she isn't. (Thought I better say that.)
And some people are tone-deaf, which is not a type of deafness at all, but rather a relative inability to distinguish tones of different pitch. People who are tone deaf will not benefit as much from the various tones that a metal detector might provide. That might affect how you set up your detector if you have the option of selecting the pitch of the auditory output.
The main point I'm making here is that one person can not tell another person what the best metal detector settings are for them. You are not adjusting your detector only to the environment, but also to your own unique sensory and information processing system. Nor can you get the best settings for yourself from a book.
You can sometimes do well with the default detector settings, but when conditions are more challenging, fine tuning becomes critical. You are not exactly like anyone else, and you are part of the metal detection system. Knowing your detector is one thing, but knowing yourself is also important. And if you want optimal performance, both you and your detector must adapt to the changing beach environment. Some days there will be more black sand, and some days the salinity will be higher, and some days there will be many easy targets, and some days not. And some days you'll be in a hurry, and some days you'll be more methodical and patient.
It is helpful to remember that signals always exist in a field of noise. Sometimes there is more noise, both internal and external, and sometimes the available signals are weaker, both of which makes the task more difficult.
Selecting the best settings for optimal performance involves decreasing the amount of noise and increasing the amount of information. Ground balancing your detector is an example of one way to decrease external noise. There are many others. And taking multiple sweeps over an uncertain target or evaluating the conductivity numbers in addition to the auditory signal are ways to add information.
You can cut down on external noise in a variety of ways. One easy and well-known method is to sweep parallel to the waterline. That might mean walking up and down the slope rather along the waterline. You can get false signals sweeping across the line between the dry sand and the wet sand created by a recent wave. Sweeping parallel to the water line will cut down (not eliminate) much of that noise. And if you adjust your detector's sensitivity to eliminate that response, you might also be reducing sensitivity to good targets. Sometimes that is acceptable, but not so much when you want to focus on deep targets and weak signals.
To sum it up, there are a lot of things to be taken into account to achieve maximum performance. You are a very important part of the system. Not only do you adjust your metal detector to the environment, but you also need to adjust it to your own unique sensory and information processing system. What is optimal for one person will not necessarily be best for you.
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| Tropical Depression Eleven. Source: nhc.noaa.gov |
Here is the cone for Tropical Depression Eleven. Doesn't look like it will do anything for us.
Happy hunting,
TreasureGuide@comcsat.net.
https://www.cns.nyu.edu/~david/courses/perception/lecturenotes/sdt/sdt.html