Questions from a fellow XT user.

[lionhrt9]

First off, want to say thank you to all that post in this section of the forum as I have learned so much from your experiences.

Through this season's snow fall I have had the time to do some research. One potential place I have to hunt is an abandoned boy scout camp that is near my house. The camp was demoed as the power company ran high tension power lines through the area. How will EMF or interference mess with my detector, I have the XT50. I know about the noise cancel feature but really have not had to deal with this before. Also I want to be able to run with relativley high sens.

#2, I just got the 10.5"DD 7.5Khz coil for the 50. Will I have to relearn the machine or is it just a different style of coil that runs better in trashy areas. I have to believe it may go alittle deeper as it is bigger than the stock coil.

#3, pinpoint with the DD, how is that going to be different.

I will put in the practice in the back yard once I get my control box back from MLab, just wanted some insight from those willing to take the time to offer it.

Thanks in advance for your help, from a relative newbie.

 

[BarnacleBill]

From a previous field test:

"Electrical Interference
******************
Normally where I hunt there is no electrical interference, so I decided to seek out interference to test three machines against one another. The Fisher Excel was chosen as a reference, since air tests showed it to have less overall sensitivity than the X50 or Edge, though other design factors may have an impact on EMI susceptibility. I sought out a small electrical generation plant that looked to have around a 50KV set of lines up on 60ft metal and wooden support structures. The coils of the machines were held in a vertical and horizontal orientation to the ground as I walked around finding the

 

[Digger]

Sounds like you may have discovered a good spot to detect. Chances are there are coins, rings, medallions and other interesting treasures just waiting for you to dig them up. Good luck on the hunts. As to your questions.....

EMF..... It is tough to predict how EMF will affect your X-50. Many variables come into play, on a daily basis. Humidity, temperature and distance from the source, to name but a few. Fortunately, you have a detector that offers 3 channels of Noise Cancel. When you arrive at the site, hold the coil horizontal to the ground to make your changes. The reason being that the coil will be in a horizontal position as you sweep the ground. I've seen guys that hold their detector coil out in front of them, making the coil vertical, with poor results. Interference received in a horizontal position might differ from vertical interference. Just as well cancel it for the coil position you want to hunt in. As to sensitivity, I don't blame you for wanting to crank it all the way up. But, as you get more familiar with the X-Terra, you will find that more is not always better. I can typically run mine fairly high around here. But the areas I hunt are moderately mineralized and are usually a long ways from electrical interference sources. If you have an interference problem in that area, and the Noise Cancel don't cure it, you will probably have to lower your sensitivity to maintain stability.

Coils..... You won't have to relearn anything with the DD coil. Both are the same frequency and both offer excellent depth of detection. Although the 10.5 inch coil is a bit larger diameter than the 9-inch stock concentric, depending on your soil conditions, it might not detect any deeper. Understanding the characteristics of each coil, concentric and DD, and the soil mineralization that you are hunting, the concentric may actually hunt deeper. With that said, proper GB should allow you to operate either coil effectively. If your soil is on the high side of moderate, the DD should perform better. But, again, remember the larger coil will also be a bigger "antennae" for that electrical interference.

Pinpointing..... I don't use the Pinpoint feature on any of my X-Terras. But I understand the theory. On a concentric coil, I merely sweep the coil over the target, from a variety of directions, making a mental note of where the center of the coil intersects itself on each sweep. That spot represents the exact center of the coil, and the target will be directly below it. On a DD coil, I also X over the target and make the same mental note. However, if you want to pinpoint, just keep in mind the principle behind the DD coil. It is "hot" from tip to base, right down the middle of the coil. So, when you cross over the target, find the center and line your coil up with it. Then, as you drag the coil back toward your feet, make note of where the signal drops off. At that point, the target is directly under the front tip of the coil.

As with any detecting tips, practice in your test garden until it comes second nature. Most of all, enjoy the time you spend in the hobby and let us know how you do!!! HH Randy

 

[NH Bob]

Being the old country boy that I am. All I can do is give it to you straight up.
I have had very little trouble with what I call high tention lines. Worst cases a little sputter once in a while.
The DD coil to me makes for a quieter machine than the concentric.
Like Digger I never use the pinpoit on any machine. I find it much faster to criss cross the target and you got it. Maybe this takes a little practice. I've always done it so its natural.
In any case you're going to get all kinds of personal preferences to this question. So take it all in and do what works for you.
I find the 10.5" DD is what makes the machine for me. I am a coin and relic hunter. HH

 

[lionhrt9]

Just got back from a drive by on the camp looking for good parking. Looks REAL promising. Thank you for the info. so far. Im biting at the bit to get out, as are my fellow MDers. Sounds like we are going out to the camp Sun. morning. Unfortunately I have to take my backup, ACE250, as MLab has the control box till next week fixing a headphone icon prob. But we are going on an exploratory mission anyway.

Digger - we are talking mod to high min soil up here in NW In. thus the choice for the DD. From your post I understand ALOT more about the noise cancel situation and will spend more time GB. Typically I have the mach GB in 10-15 sec. and don't think I'm getting it all the way.

EMF - these lines are like 50ft off the ground and are running to step downs stations far from here, don't know the KV but assume its alot. I will mess around with the noise cancel and starting at sens around 16 (what I typically run at) just to see how she reacts and reduce sens from that point. Interesting how you point out the noise cancel with the coil position, I never thought about it. I have only used noise cancel once near a power source (it worked and I moved on).

DD coil - Also didn't think about the size of the coil around the H tension power lines!! This may also force me to lower sens just to get a quiet mach.

Pinpointing - In my mind now what I'm thinking is in straight lines instead of cones. So here we go. Pinpointing with the DD may even be easier,..... I have 10.5 inches to sweep the target and 90 degrees of that 10.5 inches. Match the x and that's the target. One step further, once I have the target I can hold the PP and drag the coil back toward me until the sig disappears, then it's in front of the loop. Further, without running an X pattern I should be able to locate by just finding the hort. and drag the coil back to me for the vertical.

Wow, think I'm reaching here, esp without any swinging time with the new coil. I guess I'm trying to get concepts.

Thanks again for the info.

 

[lionhrt9]

Thank you for the input and time NH Bob. I was told by a friend that the DD coil didnt add enough bonus versus the stock coil to justify the extra weight. I wanted to try my own pants on and took a shot. I figure, im adding almost 2" to the coil and just for that minus the DD fashion, im going to add weight.

In my opinion i think the weight actually bal. the mach nicely. But I started with the Ace 250 which is bottom heavy with the stock coil.

Thanks again for the response and see above for the update. These lines are NOT going to give me fits!!! Because of some of your posts I elected to get the DD and try her out. Thanks.

 

[lionhrt9]

That is good research!!! I was informed that the XT series actually was prone to EMF interference more than other mach. Im happy to know that the features that they built into them are on the go detecting even with the surrounding environment.

Day to day our hunt spots are being encroched upon by the concrete jungle. Good to know we have some combat against that.

Thanks for your post and time.

 

[Digger]

get out there and hunt! You have the detector, the concept and what sounds like a promising site. Let us know how it works out! HH Randy

 

[John LA]

from power lines. Voltage level, insulator quality, how well connections are made, dirt (dust or pollution)on insulator, humidity, nearness to lines, etc. Interference could be harmonics but most likely arching of insulators, arrestors, or between stacks of these or internal to them. Could even be caused from "power line carriers" (RF transmitters) operating on power lines (used for protective relaying).

 

[lionhrt9]

As posted can not wait to go. Just getting insight, and still frozen up north.

Will keep ya all updated!! Just feeling out the ranks as I have the time too.

One more thing, as if I need it. Ive been using rechargable batts. Nimh I believe.

From prev. posts. I guess I should use reg. batts. new to get performance out of the machine.?? Just another question.

 

[NH Bob]

n/t

 

[NH Bob]

n/t

 

[lionhrt9]

another L??

Didnt get it.

 

[NH Bob]

n/t

 

[Bavaria Mike]

I have the XT70. The 10.5" 7.5 Khz DD gets some amazing depth, really surprised me and finds very small targets, I will not use the 18.5 Khz coil on a farm field! It pinpoints very well however, aluminum foil type targets can through off the pinpoint a little. I have to dig those signals as that is where small silver coins hit here in Germany. No learning curve, it is just a better coil and separates targets very well. I have dug several targets that were masked by iron, hit/heard both targets within a few inches, dug and recovered a nail and a button from the same hole. It will sometimes cluck like a chicken when something is being masked or targets are very close, work around the sides with the coil and I can usually separate the targets and even pinpoint them individually, I am amazed a DD coil can do that! I run in all metal and the recovery speed between targets is very fast however, I have heard if you notch out something it slows down the recovery speed. I have detected under power lines with no interference at all, if I went over underground lines, I did not notice. I have detected beside a friend and we could get our detectors very close together before any interference started. If ML comes out with a small coil, the XT will clean up the goodies in trashy areas, I'm hoping for a larger coil myself. Hope that helps and HH, Mike

 

[seaweednh]

These batteries, POWEREX 2700 mAh AA NiMH Rechargeable Batteries, will take care of your low battery problems.

http://thomasdistributing.com/maha_2700_rechargeable_batteries.php

I found these some time ago when I couldn't keep a set of batteries in my GPS. Went from approx. 2 hours to 7-1/2 hours with these. It's all in the mAh. (it may also help that I bought the "high tech" charger they offer as well) http://thomasdistributing.com/mhc401fs_buy.php3

As for detecting under power lines, when I was researching GPS's, some of the different brands were known to fry if you were under these lines. I bought the Magellan Meridian because they don't have that problem.

 

[lionhrt9]

Thanks Mike for the input, I am very interested in the separation as we often times get into situations where we have to detect trashy areas as good spots are becoming scarce. Will take your info into my arsenal.

 

[lionhrt9]

Just looked em up on ebay, excellent choice. I think these will even work in my current recharging stations. Very nice rechargables.