Iron Tone at 0 - Why does this work so well?

[earthmansurfer]

From limited testing on a 8 3/4" buried Nickel in my garden (with a variety of settings - but tried Rx at 8-10, Disc at 85-90, 5 - 10 band filter).

It sure seemed like the coin came through much better when I set the iron range (from -95 to -30) tone to 0. I don't think this has anything to do with the iron sounds covering/masking up the beeps, as I just didn't hear a beep at times and I was listening keenly (I just don't like to run discrimination). I wonder if this finding is a much more subtle thing regarding the circuits, processing, or the like. I've heard the iron tone 0 thing mentioned before and how it seemed to "pull" coins out of iron. Of course there is the danger that you will miss targets by not investigating iron if you run with the iron tone on 0 (unless you watch the screen) so it might be good to have discrimination off and have another program available to "investigate" the iron with iron tone set to 0 (in a part or even all of the range.)

What are your experiences and suggestions with running Iron Tone 0 and why do you think it might work?

Thx,
EMS

 

[yazoo]

Set your - VDI tones to 5 then you will be alerted to iron by the ticking sound . Yazoo

 

[Larry (IL)]

Coming from the old school of detecting, I have learned that the less discrimination, the more depth and cleaner signals you will have. Now with the faster microprocessors nowadays I really don't know if this still holds true but I like the tone assignment feature because I accept iron above the ground readings (ground rejected) but assign 0 tone so I don't have to listen to it. Some people like to know when iron is present and thus the 5 Hz ticking.

 

[earthmansurfer]

Thanks for the comments guys. I did play with the lower Hz sounds and didn't think to experiment like that. Clearly, a target will come through the "ticks" clearer than it will a regular tone. I will definitely try this!

Good point Larry regarding the processors of today. It does make one wonder but I have a feeling the Masking affect regarding using discrimination has more to do with how the code is written, signals are processes (hence the masking), etc. In other words, even with faster processors, if they haven't changed the code or processing, things may happen quicker sure, but the same result (just an idea).

That said, if anyone has an idea on my initial question (regarding the technical nature of it, pluses, minuses, etc, or if indeed it's true for you) I'd still love to hear. I know CyberSage has talked about the Zero Iron Tone pulling coins out of iron...

 

[Rob (IL)]

For the new guys this topic has been covered before. This is were the search feature of the forum is most important. Try using it. The more you read the more questions you will have.

Setting Tones to Zero
The way the code is written the detector can react faster by having it accept all targets and setting a 0 tone to the ones you don't want to hear, rather than rejecting targets. (From Anne)
Say you have VDIs -5 to +17 discriminated out or rejected and +18 and up accepted. If you have a target that starts ringing in at +19 (in the accepted range) but as the signal gets stronger, shifts to +15 (rejected). You can potentially hear the 19 and then the tone for +15 for a short time before the audio decays to silent. So, in this case, you hear a little bit of the rejected VDI due to the decay function of discrimination.

Rather than having -5 to +17 discriminated out, you have them accepted, but you set the audio for those VDIs to 0. For the same target, what you will hear is the +19 tone (for a very short time as above) but when it shifts to +15, it will immediately be silent. By setting the audio tones to 0 gets them to go quiet immediately rather than waiting for the decay of the audio. Accepting all but setting the ones you don't like to zero makes sense to me - that way you don't have the recovery masking out a good target. You hear the null over the iron, then the good tone for the good target.
Some people like to do both. If you accept the range, but have the audio set to zero, you will still see VDI's on the screen. If you reject the range instead and set the VDI to zero, you won't hear anything different - audio will still immediately go quiet on the rejected range, but the VDI's won't display. ROB