TID Normalization Question

[Iron Buzz]

I hope that somebody has the answer to this because I haven't been able to figure out how to determine it myself.

Is the target ID# normalized just prior to displaying it, or is the normalized ID also used earlier in the circuitry? In other words, is it simply a matter of the number displayed for me, or are discrimination and tones based on the normalized ID, or the ID that is based on the frequency?

 

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[vferrari]

Good question. Add that mystery to the many reasons I do not use ID NORM.

I am not sure of the answer but I do know an experiment you can attempt to try to find the answer. Use a high conductor coin. Turn ID Norm off. Scan the coin at 8 khz and at 12 khz. Note whether or not the tone frequency AND TID increase as you increase the operating frequency over the target (hint: they both should increase). Then turn ID Norm on. Scan the target at each frequency and note whether the tone increases similar to when ID Norm is off and also verify that TID DOES NOT CHANGE with the frequency change. If the tone increases with frequency then only the TID number is normalized, if the tone does not increase with frequency then both tone and TID are normalized. The normalization frequency reference is 18 khz. Hope that helps. Since I do not use ID Norm, I leave the experiment as an exercise for the reader. (lol, I have always wanted to write that). Note that you may have to use trial and error to find a target whose tone frequency increases when you increase operating frequency from 8 to 12. (I suppose you can also try 4 to 8 or 4 to 12 or 4 to 18 or any combination you desire to maximize the effect).

 

[DeepDigs]

Hi Iron Buzz,

I run in 5 tone audio, and use ID normalization. (which, as you know, shows 18 kHz numbers on the TID screen). The main frequency I hunt in is 8 kHz. I also switch frequencies often to check targets.

If you are setting up tone breaks/notches in your program AND are using ID normalization, setup your program tone breaks/notches like you are using 18 kHz. (even if you aren't)

If you switch frequencies while hunting (and have ID normalization ON), the Deus gets the signal, converts it to 18 kHz numbers, then passes that number thru your audio/notch settings, then displays that number on the TID screen. In other words, if you have ID normalization ON, set your program up like you are running in 18 kHz all the time. You can switch frequencies while hunting and your audio/notch settings do not need to be changed as you shift frequencies.

Hope that makes sense - its hard (at least for me) to explain. I agree with Vferrari though - a simple way to verify this would be to turn ID normalization to ON, then run, say, a nickel under the coil. It should read 62-63. Now, notch out 62-63, change the frequency to 4khz, and try the nickel. You wont pick it up.

Hope that helps

 

[Iron Buzz]

Hi Iron Buzz,

I run in 5 tone audio, and use ID normalization. (which, as you know, shows 18 kHz numbers on the TID screen). The main frequency I hunt in is 8 kHz. I also switch frequencies often to check targets.

If you are setting up tone breaks/notches in your program AND are using ID normalization, setup your program tone breaks/notches like you are using 18 kHz. (even if you aren't)

If you switch frequencies while hunting (and have ID normalization ON), the Deus gets the signal, converts it to 18 kHz numbers, then passes that number thru your audio/notch settings, then displays that number on the TID screen. In other words, if you have ID normalization ON, set your program up like you are running in 18 kHz all the time. You can switch frequencies while hunting and your audio/notch settings do not need to be changed as you shift frequencies.

Hope that makes sense - its hard (at least for me) to explain. I agree with Vferrari though - a simple way to verify this would be to turn ID normalization to ON, then run, say, a nickel under the coil. It should read 62-63. Now, notch out 62-63, change the frequency to 4khz, and try the nickel. You wont pick it up.

Hope that helps

I did test it this afternoon (thanks for the nudge, vferrari), but my findings were just the opposite of yours! Before I go into any details of what I found, I want to retest just to make sure of what I'm saying. But I will say that I came to the conclusion that ID Norm was simply for the display. But I'll get back to you when I'm sure.

(Ignore the next paragraph. We don't have a strikeout option)
One thing that I discovered that really disappointed me is that it no longer remembers the owner's preference when it comes to normalization. I assumed they had simply changed the initial default from "Off" to "On", but it resets to "On" when you power off! With 3.2, when I turned it on, it stayed on. (and I do run with it on). I don't think XP handled that properly.

I stand corrected. It does save your normalization setting. I don't know what I did wrong, but twice, it looked like it hadn't. Brainfarts, I guess.

I also stand corrected about everything else.

I used a silver dime which gave me a TID of 75 at 4KHz and 91 at 18KHz. The tone at 4KHz was indeed a bit lower sometimes, but at all three other frequencies (with norm off) it gave the same tone, and even at 4KHz it bounced some and gave me the same tone sometimes, so that was simply a result of being on the edge of the tone break I guess (I didn't check to verify that).

I also tested both discrimination and notch, setting each at 75 (notch centered around 75) and with norm off, the coin was ignored, but with it on, it was detected.

So... they do apply the normalization early in the processing chain, with makes it consistent throughout. Good to know.