Showing posts with label small coil. Show all posts
Showing posts with label small coil. Show all posts

Tuesday, April 14, 2015

4/14/15 Report - Comparing Very Different Types of Metal Detectors For Beach Detecting.


Written by the TreasureGuide for the exclusive use of treasurebeachesreport.blogspot.com.

Treasure Coast Gold Dug Yesterday.

Here is just over one ounce (1.05) of 14K gold dug yesterday.  It is marked Italy and 14K.  Acid test verifies the marking.

This is a common man's bracelet design. 

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I plan to give a brief summary of three very different detectors for beach hunting.  I'll start at the inexpensive end today with the Garrett Ace 250.

I'll preface this by saying that for many years I was not a fan of Garrett detectors..  One reason is that my first Garrett detector was a water proof PI detector. That was back sometime in the eighties.  My history up until that point included only VLF detectors including some very good custom modified gold detectors.  The custom detectors that I used almost exclusively for years nulled iron.  That was a convenient feature when looking for modern gold and when you didn't care about artifacts such as shipwreck spikes.

 I quickly learned the pulse machine was very hot on iron, and I detected many swimming holes that had a lot of bobby pins, nails and other iron trash, but that wasn't my main concern.  I couldn't get a good smooth threshold.  I didn't know at the time that the threshold tone I was getting was pretty normal for PI detectors.  I expected something more like the detectors that I had used.  I sent the detector for repairs two or three times and nothing changed.  That was my fault, but we didn't have the video instruction DVDs in those days and I just didn't know any better, so it was my ignorance combined with a lack of good information that was the problem.  It wasn't the best choice for the type of hunting that I was doing anyway, but I like to experiment and try different things.  That one didn't work out.

Another reason I didn't care for Garrett back then is that I saw that a lot of people were using Garrett detectors and not very well.  I would see what they were missing and blame the detector.  That wasn't completely fair. 

One thing that contributed to my failure with the Garrett PI was that I ordered the detector via mail order, so I didn't see it operated before I got it.  If I had gone to a retail dealer who could demonstrate the detector and provide good information, I probably would not have made that mistake, which turned out to be a poor purchase and gave me a bad impression of Garrett.  Lesson learned.

There are a number of lessons there.  If you are a beginner, or not, it might be a good idea to get a demonstration of any detector you are considering.   Sometimes a friend will let you try a detector like the one you are considering, but if it is new on the market that might not be possible.  You can get good information and a hands-on demonstration from a dealer.  That will help you make a good decision and get started quicker with your new purchase. 

As I said before, most of what I learn I learn by personal experience.  That is just the way I am and always have been.  Anything I read or hear,  I test for myself.  I do a lot of testing and enjoy that sort of thing, but you can avoid mistakes by talking to others and reading.

This is also something that dealers should remember.  You might be able to avoid a bad customer experience by providing good thorough information. 

Back to the Ace 250.  One very good thing is the price - around $250.  It is an effective detector with target ID, discrimination and multiple hunting modes.  The coil is small but that isn't all bad. You can change coils if you want.  There are others that you can buy.  For me, the small coil works fine.  Quick and easy pinpointing even without going into pinpoint mode.

It doesn't eat batteries like Godzilla either - another good thing.

It works very well on dry sand.  Depth isn't the greatest in the world, but is good for the price.  It does a good job on small objects and gold.  Not bad for a back up or as one more tool in your personal arsenal.  Also not a bad starter detector. 

The small coil can be changed if you want.  I wouldn't change it for dry beach detecting, but maybe you want to cover more ground. 

The vast majority of good targets on a dry beach are not very deep. 

The Ace and the small coil works well close to objects such as metal beach chairs.  It is also good on small gold.

In this blog I gave you a report on my first few hours with the Ace 250, which included a number of finds at an inland site.  Wheat pennies were found within the first hour and the second day netted an 1829 large cent. It was easy to assemble and begin detecting. 

Working in wet sand requires some adjustments and less depth.  Remember this is a very inexpensive detector and can not fairly be compared to detectors costing much more.  I would, however, not feel handicapped if I were using the Ace on a dry sand beach. 

It is light and easy to swing, has acceptable target ID, and won't miss much if you use it well.  It does have a fairly small coil, which is not all bad.  In my opinion, if used well it will do nearly as well as more expensive detectors on dry sand beaches. 

What I tell you is what I've personally tried and tested.  It comes from personal experience not theory or reading what somewhat else had to say. 

I've never been one to care much about how things are engineered or supposed to work.  I only care about how they actually work, as tested and proven by careful experiment and observation in real-life conditions. 

I'll get to the other detectors tomorrow or soon. 


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The Fishers estimate that there is still over $280 million to be found from the Atocha and Margarita.

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On the Treasure Coast we'll have smooth seas and South winds for a few more days.  That makes for easy water hunting if you can find some decent dips.

Happy hunting,
TreasureGuide@Comcast.net

Tuesday, March 31, 2015

3/31/15 Report - Peripheral Sensitivity And Metal Detecting Around Large Metal Objects. Spring Break In Full Swing.


Written by the TreaureGuide for the exclusive use of treasurebeachesreport.BlogSpot.com.

Detectorist On Treasure Coast
Beach Yesterday Near Low Tide

The sand is still piled up.  The nice North wind we had recently didn't do anything good to the beaches.  There were some shells, sea glass and pieces of fossil on some beaches near low tide yesterday.

Bill P., who provided me and the blog with excellent instructions on how to use Muriatic acid to clean cobs back a few years ago was down in the Treasure Coast area and said how disappointed he was to see all the renourishment sand.  That is the way it is now.

I saw this fellow in the picture detecting on feet of newly accreted sand.  He got caught on the Treasure Guide's roving beach cam.

There were a lot of people at the beach yesterday.  It looks like Spring Break is in full swing.  There are a lot of snow birds on the beaches these days.

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Bill M. had the following to say.

While researching a ghost town on the west coast of Florida, I found the Florida Memory web site which is filled with old photos, maps and articles about places in Florida from by gone days.

Not sure if you've mentioned this on your blog, but thought I'd share it with you.


I also found the ghost towns link below interesting, but not totally accurate.


Thanks Bill.

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Here is a quick video clip showing one Treasure Coast treasure beach from yesterday.


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In my most recent post I talked about the importance of knowing the area of target sensitivity for your detector coil and suggested doing air tests to determine the size and shape of the area of target sensitivity for your detector.  Today I'll discuss peripheral sensitivity a bit more.

The area of target sensitivity will be different for different coils and detectors.  The shape of that area will differ and is an important factor.  That is one thing I explained in my previous post.

What I want to talk about today is the far edge of peripheral sensitivity   By that I mean the farthest area out from the center of the coil where things can still be detected.

It might seem surprising to some, but an object doesn't have to be under the detector coil to be detected.  Most small targets do have to be under the coil, but larger objects do not.  You can prove that for yourself.   Try to detect close to a chain link fence, for example.  The fence will give a signal when the coil is inches or feet away from the fence.  The same thing will happen with any large metal object, whether it is a car, rebar in a driveway, lamp post, or whatever.  You can't detect close to those things because of the signal they will cause.

For smaller targets like coins or rings, you obviously don't get such a large signal when the coil is not over the object.   A good hot setup will detect small things under the edge of the coil or out from the edge of the coil just a touch.

Peripheral sensitivity for large objects can be an obstacle.  You won't be able to detect real close to metal lawn chairs or fences.  That provides an opportunity if you can figure out how to work close to those types of objects.  One way to do that is to select the right detector.  Some detector/coil combinations will allow you to get much closer to those types of objects than others.

Another method that will allow you to detect closer is to switch to a smaller coil.  Another is to decrease sensitivity or increase discrimination.

This is one of those situations when you might find that a less expensive or less powerful detector can work to your advantage.

Another thing you can do is to change your sweep pattern.  Sweep your coil parallel to such objects, instead of at and away from those objects.  Instead of walking along a fence, face the fence and sweep the coil parallel to the fence.


Another thing that often helps, is slowing down your sweep speed.

Those things can help you turn an obstacle into an opportunity. 

In a future post I'll talk about methods for making best use of peripheral sensitivity.

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On the Treasure Coast the surf is very small these days and the tide is moderate.   On Easter the surf is now predicted to increase to something like 4 to 6 feet.  The earlier predicted eight-foot surf has disappeared from the charts, as is often the case.

Happy hunting,
TreasureGuide@Comcast.net