Monte
"In Memory of"
Let me share a few comments that I also shared with some folks the past three days in small group detector discussion. These were a mix of some who are interested in getting into the hobby, some who have a detector but haven't used it in quite some time because they never learned it or understood it or what was going on, and a small number of guys, and one gal, who consider themselves to be more-or-less regular hobbyists and somewhat familiar with their detectors.
Some of the detectors present dated back to about 1982, and a couple of them didn't work at all or didn't work properly, and I would guess that half of the folks were not sure of what all their detector controls and adjustment functions did, or were supposed to do. Honestly, I think the three days of different small group get-togethers was really a representation of what we would have frequenting a lot of the Detecting Forums. Folks who just don't know, and some will offer up a comment or maybe a question or two.
The topics of "detector testing, and detector / search coil differences" came up and here's what I had to say:
1.. There is no such thing as a 'perfect' detector. There are a lot of inferior detectors out there, and there are a good number of very good 'general-purpose' detectors. There are also a few that are great 'G-P' detectors and are also good for more 'specialty' hunting such as dealing with dense ferrous debris.
2.. When it comes to search coil selection, do not 'over-estimate' the abilities of larger-size search coils, and also do not 'under-estimate' the performance abilities of smaller-size search coils. Search coil size selection can be a very important consideration in what you plan to use for the different site environments you plan to take on.
3.. Equally, do your best to learn the differences between two popular search coil 'types', the Concentric and Double-D. Study and experiment by testing and during your hunts to learn their 'strengths' and 'weaknesses'. They both have some of each.
4.. Never presume that just because one search coil size and type works well on one detector model that the same size and type will produce the same in-the-field performance on a different make or model detector. I can assume you that it is definitely not going to happen.
5.. Acquiring ANY metal detector means it is mandatory that6 you complete your first homework assignment. And do that assignment with pen and notepad at-hand. The assignment? Read, from cover-to-cover, the complete Owner/User Manual. When doing so, make sure you understand everything being explained or described. If you don't, jot a note of the page and particular topic you do not understand, then get out and find the answer to describe what you didn't understand.
From the manual, read and learn and know what you have, how it works, and what the different features and functions are supposed to do. When in doubt ... ask.
6.. Do you know what the EMF (Electro-Magnetic Field) looks like from a side-view for Concentric coil and a Double-D coil? I'd guess 90% of the detecting hobbyists haven't a clue, and most of them incorrectly picture the shape of the EMF much different than what it really is. (For example, if you think a Concentric coil's EMF is a 'V' shape, you are very wrong.) It's good to know the shape of the EMF and then know what the "functional portion"of that field is or looks like at different depths / distances from the coil.
7.. If you have two similar size and shape objects, with one being a ferrous wagon wheel off of an old toy and the other a similar spoke-shaped clock gear made of brass or copper, and they are both spoke-shaped and the same diameter .... which of two two is going to have a greater effect on the EMF?
Know the above in order for some detector-testing and coil-testing to be more useful for you in future searches. Now, how about 'testing' or designed 'test scenarios'?
Whn ver I get my hans on any detector, ina home, a torefront or out i detecting, there are two things I always want to do:
One is to refresh my memory of things I have learned in the past. And second is to try and learn something new. If I do tha, then it is going to add to my knowledge and abilities and increase my opportunities for success afield and having more 'fun.' It's just a hobby but we should always be learning or trying to learn. One method is by 'testing'.
Testing..: Any type of general testing can be educational and helpful.
• Test various coins to learn their audio Tone ID range and visual VDI / TID response, nd if you Jewelry Hunt, do the same with a wide-range of silver and gold jewelry of various types.
• Test coins and other anticipated find in various positions or orientations to the search coil. 'Flat' or canted at different angles or on-edge and swept from both directions.
• Use an assortment of different types of common trash, such as Iron Nails, Bottle Caps, Ring-Pull Tabs & rectangular Pry-Tabs. Position them, also, in different orientations to the search coil, and always sweep the center-axis of the search coil across the Test samples.
• Sweep the search coil at different sweep-speeds, from slow and methodical to a modest sweep speed to a very brisk sweep speed. Note the allowable sweep speed range for different makes and models that still handle the debris and also provide a decent detection signal on a good test sample near by.
• Test all of the search coils you have for each model. Note and strengths and weaknesses.
• Use different adjustment settings to find out if there are nd settings or combinations of settings that provide the better desired performance for that Test.
Test Scenarios: This is where you use a 'controlled' set-up for a Test Scenario' that duplicates an actual in-the-field encounter. Not a made-up test, but one where you duplicate a challenge that you encountered afield. One I have promoted and relied on for over 27 years is my 'Nail Board Performance Test'. It is very typical of many similar encounters I have had in my 56+ years of avid detecting when Relic Hunting ghost towns, homesteads, or any other site with a demolished or decayed structure that deposit a lot of Iron Nails in a very compact area.
Following the suggesting above, using a 'Test Scenario' can be very educational about the performance abilities of both detectors and search coils, but if you use a controlled scenario, all testing you do today, tomorrow or any time in the future will be with an exact same set-up. But remember this:
► You can never suggest a particular 'Test Scenario' using test samples of trash or using different denominations of coins and expect others to check out the performance of their detectors and coils and have any fair and useful results .. UNLESS .. both you and anyone else, anywhere else, are using the very same, identical 'Test Scenario'.
I can suggest anyone get four Pull-Tabs and a US coin and place them somewhere in a partticualr arraignment and then make any results they have and I have be comparable. All targets and samples used and positions would be different to widely different, and that would make comparisons in performance invalid.
► You CAN have some comparable controlled Test Scenarios if two or more individuals in various locations are using the exact same Test Scenario lay-out, and that's why I contracted a sign maker to duplicate the exact positions of the four Iron Nails and an Indian Head Cent that was located laying on top of the ground when I encountered them in the ghost town of Frisco Utah back on Memorial Day Weekend in '94.
I got a Nail Board Performance Test 'kit' to Nokta / Makro, White's, and Garrett as well as Keith Southern, and many other individuals have acquired a NBPT 'kit' through the years. That means all of us have the exact same target sample positioning so all of our comparisons of various makes nd models and coils will be easily comparable and useful.
► Always be willing to learn more about performance abilities or draw-backs by making comparisons. For example, I have had people comment that my NBPT isn't fair because it is all on the same plane or 2-Dimentional. Well, it is a very fair 'Test' because it is an exact duplication of an actual in-the-field encounter. I have 4 marked sweep routes on the Nail Board, and you can sweep each route from the left and from the right, making a total of 8 possible hits on the centered Indian Head Cent.
► For me and my personal desires, I will only keep detectors and smaller to mid-size coils in my regular working Detector Team that can produce at least 7-out-of-8 good clean hits or a full 8-out-of-8 on my NBPT. Any less, like only 6 or less, are detectors that might work for regular Coin & Jewelry Hunting, but fall short for me as serious Relic Hunting devices for Iron Nail contaminated sites.
► For those who want to challenge my testing, I do have two 3-Dimentional tests I do. Naturally I don't expect as high a score. One has the Iron Nails and non-ferrous Coin located at different 'depths with the 4 Iron nails positioned 1" above the Coin, and the other has them positioned about 1" below the Coin. I'll try to get some photos to post later of the three NBPT positions.
In the end I encourage anyone and everyone to better learn their detectors and search coils by testing them using an assortment of test samples and learn . That's how we get ahead in this great outdoor sport.
Monte
Some of the detectors present dated back to about 1982, and a couple of them didn't work at all or didn't work properly, and I would guess that half of the folks were not sure of what all their detector controls and adjustment functions did, or were supposed to do. Honestly, I think the three days of different small group get-togethers was really a representation of what we would have frequenting a lot of the Detecting Forums. Folks who just don't know, and some will offer up a comment or maybe a question or two.
The topics of "detector testing, and detector / search coil differences" came up and here's what I had to say:
1.. There is no such thing as a 'perfect' detector. There are a lot of inferior detectors out there, and there are a good number of very good 'general-purpose' detectors. There are also a few that are great 'G-P' detectors and are also good for more 'specialty' hunting such as dealing with dense ferrous debris.
2.. When it comes to search coil selection, do not 'over-estimate' the abilities of larger-size search coils, and also do not 'under-estimate' the performance abilities of smaller-size search coils. Search coil size selection can be a very important consideration in what you plan to use for the different site environments you plan to take on.
3.. Equally, do your best to learn the differences between two popular search coil 'types', the Concentric and Double-D. Study and experiment by testing and during your hunts to learn their 'strengths' and 'weaknesses'. They both have some of each.
4.. Never presume that just because one search coil size and type works well on one detector model that the same size and type will produce the same in-the-field performance on a different make or model detector. I can assume you that it is definitely not going to happen.
5.. Acquiring ANY metal detector means it is mandatory that6 you complete your first homework assignment. And do that assignment with pen and notepad at-hand. The assignment? Read, from cover-to-cover, the complete Owner/User Manual. When doing so, make sure you understand everything being explained or described. If you don't, jot a note of the page and particular topic you do not understand, then get out and find the answer to describe what you didn't understand.
From the manual, read and learn and know what you have, how it works, and what the different features and functions are supposed to do. When in doubt ... ask.
6.. Do you know what the EMF (Electro-Magnetic Field) looks like from a side-view for Concentric coil and a Double-D coil? I'd guess 90% of the detecting hobbyists haven't a clue, and most of them incorrectly picture the shape of the EMF much different than what it really is. (For example, if you think a Concentric coil's EMF is a 'V' shape, you are very wrong.) It's good to know the shape of the EMF and then know what the "functional portion"of that field is or looks like at different depths / distances from the coil.
7.. If you have two similar size and shape objects, with one being a ferrous wagon wheel off of an old toy and the other a similar spoke-shaped clock gear made of brass or copper, and they are both spoke-shaped and the same diameter .... which of two two is going to have a greater effect on the EMF?
Know the above in order for some detector-testing and coil-testing to be more useful for you in future searches. Now, how about 'testing' or designed 'test scenarios'?
Whn ver I get my hans on any detector, ina home, a torefront or out i detecting, there are two things I always want to do:
One is to refresh my memory of things I have learned in the past. And second is to try and learn something new. If I do tha, then it is going to add to my knowledge and abilities and increase my opportunities for success afield and having more 'fun.' It's just a hobby but we should always be learning or trying to learn. One method is by 'testing'.
Testing..: Any type of general testing can be educational and helpful.
• Test various coins to learn their audio Tone ID range and visual VDI / TID response, nd if you Jewelry Hunt, do the same with a wide-range of silver and gold jewelry of various types.
• Test coins and other anticipated find in various positions or orientations to the search coil. 'Flat' or canted at different angles or on-edge and swept from both directions.
• Use an assortment of different types of common trash, such as Iron Nails, Bottle Caps, Ring-Pull Tabs & rectangular Pry-Tabs. Position them, also, in different orientations to the search coil, and always sweep the center-axis of the search coil across the Test samples.
• Sweep the search coil at different sweep-speeds, from slow and methodical to a modest sweep speed to a very brisk sweep speed. Note the allowable sweep speed range for different makes and models that still handle the debris and also provide a decent detection signal on a good test sample near by.
• Test all of the search coils you have for each model. Note and strengths and weaknesses.
• Use different adjustment settings to find out if there are nd settings or combinations of settings that provide the better desired performance for that Test.
Test Scenarios: This is where you use a 'controlled' set-up for a Test Scenario' that duplicates an actual in-the-field encounter. Not a made-up test, but one where you duplicate a challenge that you encountered afield. One I have promoted and relied on for over 27 years is my 'Nail Board Performance Test'. It is very typical of many similar encounters I have had in my 56+ years of avid detecting when Relic Hunting ghost towns, homesteads, or any other site with a demolished or decayed structure that deposit a lot of Iron Nails in a very compact area.
Following the suggesting above, using a 'Test Scenario' can be very educational about the performance abilities of both detectors and search coils, but if you use a controlled scenario, all testing you do today, tomorrow or any time in the future will be with an exact same set-up. But remember this:
► You can never suggest a particular 'Test Scenario' using test samples of trash or using different denominations of coins and expect others to check out the performance of their detectors and coils and have any fair and useful results .. UNLESS .. both you and anyone else, anywhere else, are using the very same, identical 'Test Scenario'.
I can suggest anyone get four Pull-Tabs and a US coin and place them somewhere in a partticualr arraignment and then make any results they have and I have be comparable. All targets and samples used and positions would be different to widely different, and that would make comparisons in performance invalid.
► You CAN have some comparable controlled Test Scenarios if two or more individuals in various locations are using the exact same Test Scenario lay-out, and that's why I contracted a sign maker to duplicate the exact positions of the four Iron Nails and an Indian Head Cent that was located laying on top of the ground when I encountered them in the ghost town of Frisco Utah back on Memorial Day Weekend in '94.
I got a Nail Board Performance Test 'kit' to Nokta / Makro, White's, and Garrett as well as Keith Southern, and many other individuals have acquired a NBPT 'kit' through the years. That means all of us have the exact same target sample positioning so all of our comparisons of various makes nd models and coils will be easily comparable and useful.
► Always be willing to learn more about performance abilities or draw-backs by making comparisons. For example, I have had people comment that my NBPT isn't fair because it is all on the same plane or 2-Dimentional. Well, it is a very fair 'Test' because it is an exact duplication of an actual in-the-field encounter. I have 4 marked sweep routes on the Nail Board, and you can sweep each route from the left and from the right, making a total of 8 possible hits on the centered Indian Head Cent.
► For me and my personal desires, I will only keep detectors and smaller to mid-size coils in my regular working Detector Team that can produce at least 7-out-of-8 good clean hits or a full 8-out-of-8 on my NBPT. Any less, like only 6 or less, are detectors that might work for regular Coin & Jewelry Hunting, but fall short for me as serious Relic Hunting devices for Iron Nail contaminated sites.
► For those who want to challenge my testing, I do have two 3-Dimentional tests I do. Naturally I don't expect as high a score. One has the Iron Nails and non-ferrous Coin located at different 'depths with the 4 Iron nails positioned 1" above the Coin, and the other has them positioned about 1" below the Coin. I'll try to get some photos to post later of the three NBPT positions.
In the end I encourage anyone and everyone to better learn their detectors and search coils by testing them using an assortment of test samples and learn . That's how we get ahead in this great outdoor sport.
Monte
