Treasure Talk blog posts on the X-TERRA 305
A little over a year ago, Minelab authorized Coiltek Manufacturing to produce the 15-inch All Terrain 7.5 kHz DD coil for the X-TERRA. Since its release, the medium frequency 15-inch X-TERRA coil has been proving its capabilities to coin-shooters and cache hunters across the globe. However, recognizing that there are many other forms of “treasure hunting”, Coiltek continued working with Minelab in an effort to develop additional coils for the X-TERRA lineup. These efforts have paid off in the form of three addition X-TERRA coils. They include a new 15-inch All Terrain Double-D at 3 kHz, a 15-inch All Terrain Double-D at 18.75 kHz and a small 6-inch Double-D at 3 kHz.
So where will you be hunting? Do you need a waterproof coil, or is water resistant enough?
According to Minelab, waterproof means it is submersible to one meter, making it ideal for shallow water hunting.
The X-TERRA coils that are considered waterproof include the 6-inch concentric at 7.5 kHz, the 6-inch Double-D at 18.75 kHz, the 9-inch concentric at 3 kHz, the 9-inch concentric at 7.5 kHz and the 9-inch concentric at 18.75 kHz.
There are several things to be considered when choosing a coil for your X-TERRA. In Part 1, I mentioned that larger coils detect larger targets deeper, small coils are more sensitive to smaller targets, concentric coils provide a more accurate TID, and Double-D coils separate targets better than comparably sized concentric coils.
In Part 1, I discussed some generalities in coil performance. In Part 2, I’ll explain how I determine whether a Double-D coil might improve performance in your soil conditions.
My procedure on how to best determine whether you might gain performance by switching to a Double-D coil is the same, regardless of the model of X-TERRA you are using...
One of the most commonly asked questions by X-TERRA metal detector users is, 'which coil is best for me?' Although that may seem to be a fairly simple question to some, the coil that provides the best results in one part of the world won’t necessarily be the best choice for another. And the coil that performs best for one aspect of the hobby won’t necessarily provide the best results for another. Reaching the right conclusion can be complicated until you understand the differences in coil design and application.
In Part 1 of my blog post concerning Coiltek’s new 15-inch ALL TERRAIN 7.5 kHz coil for the X-TERRA, I described the physical differences between it and two other 7.5 kHz coils available for the X-TERRA. In this portion of my blog, I will discuss the performance of the Coiltek coil in places I typically hunt for old coins.
Coiltek Manufacturing recently invited me to help field test a new 15-inch ALL TERRAIN 7.5 kHz coil for the X-TERRA Series. Having been involved in field testing the first series of the X-TERRA Series for Minelab, and recognizing the number of X-TERRA users who had expressed their interest in a large Double-D coil, I welcomed the opportunity. I’m familiar with Coiltek products, having used several models on various detectors. So when I opened the box and saw the large, round, 15-inch Double-D coil designed for the X-TERRA, the orange color did not surprise me. Instead...
For several years I have been receiving regular emails from X-TERRA users asking, “When will Coiltek release a coil to suit my detector?”. We have listened to these requests and I am now pleased to announce that the wait is over!
In a collaborative effort with Minelab, we have produced a 15-inch ‘All Terrain’ X-TERRA 7.5 kHz (medium frequency) Double-D coil that is fully compatible with Minelab’s VFLEX technology.
I've been metal detecting since 1972. I like to hunt for old coins at old sites, with the term "old" being relative to where I live. During that time, I've owned and used just about every land detector that hit the market. As time went by, like many of you, I found many of the "old reliable" sites that I hunted were producing fewer and fewer good coins. When Minelab included me in the original field tests for the X-TERRA, I had high hopes that this new technology called VFLEX would increase my finds. As soon as I got the X-TERRAs out in the field, I knew I had my hands on something special.
Well, it all depends on what you are looking for? There are three frequencies available: (1) Low, (2) Medium & (3) High.
The Low Frequency of 3kHz would be well suited to searching out metals of a high conductivity such as copper and silver coins. It might be considered a good cache hunting coil. Useful also in hunted out parks for deeper silver coins which are masked by trash items.
The Medium Frequency of 7.5kHz is...
When it comes to sweep speed, the X-TERRA is a very forgiving detector. You can operate with a relatively quick sweep in wide open areas, and slow down when targets are abundant. But to gain a better understanding of how sweep technique may affect the quantity of our finds, let's first analyze the field of detection for both the X-TERRA Concentric coils and the Double-D coils.
Based on my field analysis, with the center of the coil as the "hot spot", I find the field of detection for a Concentric coil will go "straight down" until you reach approximately 55 - 60% of the maximum depth for a specific target. In other words, if you are capable of detecting a target at maximum of 10 inches, you will find the circular field of detection begins to narrow at the 5.5 to 6 inch depth level.
With "old" being a relative term, I hunt for old coins at old sites. The part of the world that I live in wasn't settled until the mid 1850's. So finding coins older than 1900 is considered to be a good hunt. Many of my favorite spots to detect are old homesteads and farm sites. With the houses and out buildings long gone, to the passerby, most of these places look like any other corn field in this part of the Country. Pieces of brick, stone, glass and pottery are some of the things that I look for when wandering across these corn fields. And when I start hearing the low tones produced by nails and other "farm trash", I know I'm getting close to where I want to be...
Part One of this blog post described how the X-TERRA categorizes targets, based on their conductive values. In Part Two, learn how to increase your opportunity to detect jewelry and old coins by modifying the preset Patterns.
Now that I've outlined how the ferrous vs. conductive properties are represented by the visual and audio TID, let’s evaluate some targets. If you turn your X-TERRA 70 or 705 to the Coin/Treasure Mode, and set it to hunt in factory preset Pattern 2, you will be rejecting notch segments -8, -6, -4, -2, +2, +4, +6, +14, +16, +18, +20, +22, +24, +26 and +48. You will be accepting notch segments 8, 10, 12, 28, 30, 32, 34, 36, 38, 40, 42, 44 and 46. Those of you who have performed target ID tests with your X-TERRA know that this setting will accept U.S. pennies, nickels, dimes, quarters, half dollars and dollar coins. A Coin hunters dream?
A guide for US coin-shooters
A metal detector does exactly what the name implies. It detects metals. Set to accept everything, you will find nails, foil, pull tabs, jewelry, coins, tokens, relics etc. Anything that is metal. In order to avoid digging those targets you don't want to dig, we implement a feature known as discrimination. Metal detector discrimination is basically the same for all makes and models. Some may do it better than others, but the theory is universal. Simply put, discrimination is the ability to adjust your detector so that it accepts most of the targets you want to dig. And, rejects most of those targets you don't want to dig.
I have heard from some users that have tied themselves into knots when trying to find the best settings for their detector. This can happen because there are some combinations of settings that don’t work well together and there are some lesser used settings that you may have set and then forgotten to check.
In these cases please remember to perform a Factory Preset. This will return your detector to the settings that it contained from the factory.
Why are there so many coils available for the X-TERRA series of detectors?
Currently, there are eight coils available to suit your X-TERRA detectors.
All of them do mostly the same, detect metal but a few of them are ‘specialist’ coils more suited to a few tasks “the Pros” or seasoned hunters indulge in!
While there is absolutely nothing wrong with the “stock 9 concentric” that comes as standard kit with a lot of X-TERRA’s, the option to customize your detector without shelling out buckets of money is offered through what’s termed as VFLEX technology available only on the X-TERRA range.