Trueman

On 11/6/2022 at 3:23 PM, Steve Herschbach said:

A low/high signal only means "large/strong target" and high/low means "small/weak target". The tones correspond exactly with other dual tone PI detectors like all the Minelabs and the Infinium, as it is a byproduct of the dual channel ground balance system. The flip point between the two signals is determined by the current ground balance settings, but tends to end up somewhere in the region of a zinc penny when in bad ground. Just where depends on the exact ground and ground balance setting. In mild ground it could be far different. I need to experiment more with that, plus determine where the default setting is at.

If you get a target right at the tipping point, you will get a weird "tone flipping" response, that is actually a third tone indication.

The TDI and Fisher Impulse, as single channel models, have a simpler tone arrangement, either low, or high. However, the basics are the same. I wrote an extensive article on all this, referencing all my previous articles, for those that want to delve into how to use a ground balancing PI detector to discriminate items. The secret is knowing that is not about target composition so much as it is about target size and conductivity, with ferrous on both sides of the scale, small on one side, and large on the other. So small gold / low conductors and small ferrous read the same. Large ferrous and most coins / high conductors read the same.

The intensity of the tones or length of the tones is an indication of how close the target is to the coil and may be related also to the size of the target.

The ferrous check is just that, a crude and rather inaccurate iron id system. It works halfway well in ground with low naturally occurring iron minerals, but will tend to call non-ferrous items as ferrous, if the ground contains a lot of naturally occurring iron minerals. A positive “grunt” is an iron indication. Any other response at all means “not iron” but again, this system is easily fooled in high mineral ground.

Read the article I linked to above, and also the links it provides for details. Ultimately, the only way to learn is to use the detector while paying close attention to the tones, and using the iron check, and digging all targets found, for 50 - 100 hours of detecting.

Hi Steve, thank you for your extensive answer.

I give myself some time to read and think about what is written in articles you so kindely share with me.

I came across an artice about how is done Gbpi detector with no detection hole. There was written article about pairs of frequencies that reapet in order to exclude the detection hole. Each of these frequencies must be different from the other one, it make sense to me. But I want to ask you. It is the defference between them only in khz or is it something else?

Hi friends from US!

While doing my deep research on atx, to really understand how this technology works. I struggled to identificaing targets based on audio tones. Yes, I know that Pi machine has poor ability for recognition targets. But while motion mode provides dual tone audio feedback, I keep wondering about message that provides me. That scale of tones may varying from hi/low to low/hi and that is my question. If tone starts with very short low tone with long hi tone echo, what I can predict about target material? And otherwise. If target get you short hi tone followed by long low echo, may I assume that the long echo tone assigning the target to the scale of material corresponding to the tone? So if I get short low tone followed by long hi echo, target response should be somewhere close to low conductive material? Even if the complete audio response is low/hi indicating good conductor?

Is there any advice how I can be better in recognition targets based only on audio response, beside to dig everything what Iron check doesnt recognize?

How the iron check actually works? Can I use it to helping identificaing targets, even if they are not iron. I have noticed that if I swing over for example pulltab in Iron check mode, it does not make any difference(off course it did not), but when the audio is non existent in Iron check, what that can tell me?

Before You ask why I decide for atx ( If you dont know Iam a begginer) I am also motorcycle enthusiastic and my condition for packing are limited, so this is numero uno for me, and offcourse the military housing just ring a bell for me.

Thank you for your time.

Greetings

René