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View Full Version : E-trac thought process in heavily hunted/trashy parks



Viking
03-30-2011, 11:52 PM
Hi all. As a newish E-trac owner (20 hours under my belt), I've been reading as many E-trac posts as I can get a hold of to help my learning curve. The key messages from my research seems to be that it takes time to listen and understand what the machine is telling you, and to go sloooow. The tips and tricks offered on this site have been very helpful but I was hoping that you all could help me with more of a specific question...

In heavily hunted parks (with lots of iron trash), I've been using Angel's settings and going as slow as I can muster. I'm finding the easy, shallow targets but I haven't had as much luck in picking out the goodies from the trash, probably because I'm not sure if I'm evaluating my signals correctly. Let's set up a common example: as I crawl around the grass, I'm getting a constant string of tones from the E-trac while I'm focusing in on the high tones. Suddenly I get a high tone and I look down at my VDI numbers and it says 35-47 about halfway down the depth scale, so I'm guessing it's iron, but I don't want to walk away yet. I wiggle the coil a bit and check the signal from all sides in 90 degree increments. While doing this, the Fe number is generally above 27, but maybe 20% of the swings give me a number like 12-44 or 16-44. I switch over to Quick mask (all metal) to check the item again and it jumps down to the bottom right of the screen, but also continues to tease me with an occasional signal in the 12-16 Fe range. Pinpointing seems inconsistent. Ultimately I start digging only to find a rusty nail, or worse, nothing at all. :dontknow:

Could some of you pros walk me through your exact steps and thought process when you're in this situation? I try to stay patient and keep myself moving slowly and being thorough, but I find myself cherry picking after I strike out enough times. Any steps you can recommend from the time you receive the questionable signal, until the time your digger hits the ground, would be great. Also, a general theory question: if you wiggle your coil over a piece of rusted iron enough times, will it eventually give you a Fe reading in the teens? Perhaps if the Fe numbers are trading off between low and high 50% of the time, it's diggable, but in my 20% example, you'd walk away?

I really think it could help me to turn the corner with the E-trac. |:confused:) Thanks.

Lowjiber
03-31-2011, 06:51 AM
Also, a general theory question: if you wiggle your coil over a piece of rusted iron enough times, will it eventually give you a Fe reading in the teens? Perhaps if the Fe numbers are trading off between low and high 50% of the time, it's diggable, but in my 20% example, you'd walk away?


I don't know squat about E-Tracs. However, I'll throw a guess at a possible explanation of the above situation...

Many machines with good ground tracking features can detune if the coil is hovered (wiggled) over an iron target too long. The machine simply thinks it's compensating for a change in ground mineralization. In practice, it's actually partially masking the target's iron content.

I don't doubt that a nice machine like the ET will do the same.

Just my uneducated $0.02.

Bell-Two
03-31-2011, 08:45 AM
From what you described you are most likely right it is iron falsing, when rotating and getting signals it is not unusual to get a 12-44 in that amongst all the high ferrous numbers, most likely when you are getting that number is that you are hitting on the tip of a nail or wire. Given the parameters I most likely would pass it up or switch into the TTF mode and see what it tells me.

Viking
03-31-2011, 02:56 PM
Thanks Lowjiber and Bell-Two. I've been using Andy's discrimination pattern, but I think I should modify it to show Fe 28+ blacked out as well (as suggested on this forum). That might help me lower potential iron falsing/wrap around issues.

I'm going to hunt a modern school or two next, just to get the feel for clad and to keep building experience. Of course I want to be finding oldies and goodies right away, but I also don't want to put the carriage too far in front of the horse. The fact of the matter is that I don't have enough experience yet to assume that I can waltz into a heavily hunted area and find what other experienced md'ers have missed over the years, just because I have the machine to do it.

Keep the advice coming though :yes:

1147SILVER
03-31-2011, 07:51 PM
go at it in a crawl speed and grid off the area and be sure to noise cancel be patient it will come as george and angel several questins daily!!!!!

coinnut
03-31-2011, 09:02 PM
Angel is the park guru lol He can tell you way more that I ever could. Now if you want to hunt foundations I can help you ;) But as a guess for deep signals in a park, you must try and shorten your swing to and inch of either side of the target, once you hear it in the first place. By moving only a very small bit, you can see if the target repeats in the same spot. A nice high tone, even if it's very faint, in the same spot is what you are looking for. I see so many people swing over a target and move their coil all over the place, never really passing the same spot over the signal. In other words if you get the target under the center of the coil and this is where it sounds best, shorten that swing to two inches across and make sure it is always passing under the same spot of the coil. Don't swing wildly from top to bottom of the coil. Pinpoint it, so it is in the center of the coil and then re-listen to it in discrimination mode. As Bell-Two said, you will eventually hover the coil over the end of the nail and it will sound good, but will not pinpoint there. Also, I never trust the numbers on the open screen, since it will usually catch the iron numbers and not the coin next to it. Just my way of looking at it.