705 settings

[reffitt20]

I have X-terra 705 with stock 9" concentric coil. What setting should i set for deep silver coins. I took it to my church and had everything notched out except 32 and above with manual ground balance tracking on and in about an hour pulled out a couple dollars in qrts and dimes. the sounds were clean and clear but I wasn't hitting anything deep. So I ask what setting should I set to get depth when Sniffing silver coins? thanks in advance you guys are great for info and I am grateful.

 

[hitchhiker]

How high did you get your sensitivity? Its better to use all metal or pattern 1 or 4 and if you get a signal thats below 32 then ignore if you only want to dig high signals.if it jumps from high to low then dig them as well.With high discrimination it effects the recovery and the response speed. Its ok if silver coins are flat they will give a high reading on the tid if the silver coins are at varying angles and depths they might not give such a high reading as the detector is not seeing enough of the coin.Its best to sweep very slowly and scrape the grass or soil with the coil if you are looking for deep coins, you might already be doing this but i thought i would mention it anyway. GL HH

 

[atomicscott]

Hitch is right on. I try to always be touching the grass or skimming the ground a bit to get the best depth. Definitely try to use all metal and 99 tones. When you get a higher tone that jumps out of the surrounding tones and ID is in the 30's dig it! Also keep in mind that some silver coins will read in the mid to high 20's if it is very close (1/2" or so?) to rusty iron. On tests using my 505, a merc dime will hit a solid 27 when next to a large rusty nail. If you dig all higher tones, (not worrying about the ID#s) you won't miss much. If you want to get the most out of the X-Terra, be sure to download Digger's ebook 'Understanding your X-Terra' on the Minelab site.

 

[mapper65]

With high discrimination it effects the recovery and the response speed. Its ok if silver coins are flat they will give a high reading on the tid if the silver coins are at varying angles and depths they might not give such a high reading as the detector is not seeing enough of the coin.Its best to sweep very slowly and scrape the grass or soil with the coil if you are looking for deep coins, you might already be doing this but i thought i would mention it anyway. GL HH

Definitely my thoughts exactly. I'm mainly a coin shooter and I typically hunt with -8, 46 & 48 notched out and that's it. If it's trashy I have a modified pattern that uses just a little more discrimination.

 

[Dirt Hound]

I've modified Pattern 1 to be wide open... nothing notched. I prefer to hear everything that is in the ground... it's good to know when you are in heavy iron. It means you need to SLOW DOWN. If you have iron notched out... you may be swinging too fast and masking the good targets. 99 (2 tones is great, too... takes some getting used to, but once you do, you will never go back.

My general settings:

Pattern 1 - wide open
Ground Tracking ON
Sensitivity 24-26
99 tones

Important to note that I've mostly been hunting farm fields... settings may vary depending on the site. For instance, we hunted a site a while back where all the coins were being found no deeper than 3-4 inches. In this case, I turned the sensitivity down to 18 which reduced the chatter while allowing me to still find the coins with no problem. But if you are looking for deep silver and copper... high sensitivity, no discrim, and slowwww swing speed is a must, IMO.

 

[BillF]

Am I missing something? Pattern 1, wide open, nothing notched. Isn't that the same as all metal?
Just curious.

 

[Old Longhair]

Not exactly Bill. Though very similar, there is a very perceptible difference. Running zero disc in Disc operation causes the machine to try to better define a target and place it in an ID slot, effectively reducing some "jumpy" TID situations. In AM the signal return is not filtered at all, and you hear everything as it is.

 

[Dirt Hound]

A nice little tip I got from Old Longhair himself I am convinced that there is NOTHING he doesn't know about the 705!

 

[Old Longhair]

A nice little tip I got from Old Longhair himself I am convinced that there is NOTHING he doesn't know about the 705!

I appreciate the praise, but wouldn't go nearly that far.

After a few years on this machine, I still learn or work to confirm on virtually every outing. There are so many facets and nuances to the 705 that I plan to investigate, that it will take years yet before I claim personal proficiency.

 

[BillF]

OK, thanks OLH. Guess I'll be trying something else new.

 

[Digger]

Good explanation OLH. I might add that Notch discrimination allows the user to accept or reject specific ranges of targets, based on their conductivity. When you pass the coil over a target, the X-TERRA analyzes that target and provides the user with the "bin number" most closely resembling that target's conductive properties. For example, on the 70 and 705, there are 28 notch segments. Each of those notch segments has a defined set of conductivity values. The lowest number, -8, represents the least conductive (most ferrous) targets you will encounter. In turn, the highest number, +48, represents the most conductive targets (least ferrous) that you will encounter. But what if a target has a conductive value that is less than (or greater than) those recognized by the discrimination software? Simple.....you won't detect them. Fortunately, I've not been able to come up with anything of value, that I would miss by using Zero Discrimination. If you take a look at my eBook (pages 34 - 37, pages 76 & 77 and pages 86 & 87), you will see where I describe this, as well as my Circular Discrimination Theory. HH Randy

 

[Old Longhair]

Thanks for a much more elaborate explanation Randy!
I bow to the man who really does know everything about the Xterra line.

I thought about just saying that it's all in the book. I encourage everyone that I can to keep going back to it after each hunt, or whenever they have a question, because it continually amazes me just how much easy to read and understand information you selflessly wrote for us.

 

[Digger]

Thanks OHL. But I don't know everything there is to know about it. I just have the good fortune to have used it longer than most. Even after all these years, if I'm paying attention, I still get an education each time I use it. HH Randy

 

[atomicscott]

Good explanation OLH. I might add that Notch discrimination allows the user to accept or reject specific ranges of targets, based on their conductivity. When you pass the coil over a target, the X-TERRA analyzes that target and provides the user with the "bin number" most closely resembling that target's conductive properties. For example, on the 70 and 705, there are 28 notch segments. Each of those notch segments has a defined set of conductivity values. The lowest number, -8, represents the least conductive (most ferrous) targets you will encounter. In turn, the highest number, +48, represents the most conductive targets (least ferrous) that you will encounter. But what if a target has a conductive value that is less than (or greater than) those recognized by the discrimination software? Simple.....you won't detect them. Fortunately, I've not been able to come up with anything of value, that I would miss by using Zero Discrimination. If you take a look at my eBook (pages 34 - 37, pages 76 & 77 and pages 86 & 87), you will see where I describe this, as well as my Circular Discrimination Theory. HH Randy

Thanks for that response Digger, but something puzzles me regarding conductivity. I recently dug a 1977 Canadian dime that sounded and ID'ed 36-39 like a standard clad (or silver) dime. Upon digging it and seeing the gray color, I got excited that it may be a silver dime. After seeing the date and checking online I found out it is nickel. Since nickel is a much lower conductor than copper or silver, I wondered why it would not ring up as a nickel if the notches/bin segments are based on conductivity? It seemed to me that is was classifying the coin based on size, not conductivity.

 

[Old Longhair]

Scott, it's because target ID is partly dependent on size, and not just conductivity. The same reason that a nice new shiny bottle cap will try to convince you that it's a quarter.

 

[Digger]

The only reasons I can come up with would be an adjacent target, too high of Sensitivity, improper ground balance, or an electrical interference problem. Unfortunately, once excavated, it is extremely difficult to duplicate the situation. Out of curiosity, what does it read, now that it is out of the ground?

As to numbers and notch bins.......the notches are set, based on what we commonly refer to as conductivity. However, what we call conductivity is actually a number that the engineers assigned to a given target (and associated notch segment), based on the time constant (delay) between the transmitted signal and the receive signal. The target's time constant is determined by the metallic conductivity of the target, and it's inductance. Inductance is the

 

[Old Longhair]

I dig a lot of Canadian coins, being so close to the largest northern border crossing.

So to further explain/complicate/confuse things, consider that Canadian dimes are pure nickel, as opposed to our nickels that are a copper-nickel alloy (75%Cu/25%Ni). Then think about the range zinc pennies come in at being nothing more than a copper jacketed zinc core (97.5%/Zn 2.5% Cu).

Now think about this part of Randy's explanation, "Inductance is the mass of the eddy currents, based on the size of the eddy current path." Then couple it with this part,"what we call conductivity is actually a number that the engineers assigned to a given target".
Being an all digital format, it's all about programming and various value assignments. It's why sound nuances count for more than displayed numbers or even tone pitch, and why I keep referring to "coin sized" or "coin sounding" targets.


Great stuff you posted Randy!

 

[atomicscott]

Scott, it's because target ID is partly dependent on size, and not just conductivity. The same reason that a nice new shiny bottle cap will try to convince you that it's a quarter.

Thanks Longhair, that is exactly what I said. Conductivity seems to be a much smaller part of the equation than size, at least when it comes to coin sized objects. So it seems that notching something based on conductivity isn't going to be very accurate.

 

[Old Longhair]

Scott, it's because target ID is partly dependent on size, and not just conductivity. The same reason that a nice new shiny bottle cap will try to convince you that it's a quarter.

Thanks Longhair, that is exactly what I said. Conductivity seems to be a much smaller part of the equation than size, at least when it comes to coin sized objects. So it seems that notching something based on conductivity isn't going to be very accurate.

I wouldn't say "smaller", but more like it plays an equal part of a balance of several programmed determining factors. Don't forget that distance from the coil plays a part in perceived size.

 

[atomicscott]

Thanks OLH, Very true. The dime was about 3-4" deep and it reads the same in ground and out of ground. I guess the disc is an intricate tapestry of conductivity, size, shape, mass, etc...I always think it's funny when someone finds an item and says 'it must be silver, it's hitting a 38!". Like Digger says, we just gotta dig it to know for sure (paraphrased of course!)