This was mentioned by geof_junk in another thread and had a little Google.
Found this https://www.phys.k-state.edu/reu2011/nnorvell/Metal_Detector_Research.html
I don’t really understand the technical side of metal detectors. Does this have any application to current day detectors? Will it help cancel out ground noise more? Will the current crossing/not crossing the ‘bridge’ tell you something about what is under one of the receive coils.
Although I don’t understand it, I am amazed and a little in awe of those that do 👍
This is a topic relevant to every(?) form of detecting -- ground coverage. I'll list several questions concerns I've had but any replies of course aren't limited to these, nor do they need to address any of them. Just tossing out some ideas to prompt further discussion.
1) What methods and efforts do you apply to ensure full ground coverage in the cases where that is one of your goals?
2) Is your sweep a straight line path or an arc?
3) How long is your sweep?
4) How much do you overlap consecutive sweeps in the direction you walk?
5) How much do you overlap side-to-side swings when following parallel paths (e.g. when walking two side-by-side swaths in the same direction how much does the left end of one path overlap the right end of the next path or vice-versa)?
6) Have you ever measured your coverage? How well do detectors with GPS (e.g. Minelab GPZ-7000 and Minelab CTX-3030) monitor ground coverage to this detail? Have you used other devices to measure ground coverage. E.g. I can imagine a drone with camera could provide useful data. Are there smartphones app that would help quantify coverage?
If this question has been addressed elsewhere, I apologize in advance and hope someone can give me a link for it. I have noticed that other companies besides Minelab are coming out with PI detectors for less than $3K. How do these detectors compare to the best Minelab detectors for Gold and also relic hunting?
On the Anfibio Multi (and I think Kruzer & others) there is a definite step in sensitivity between 39&40 Gain and again between 69&70 Gain. Is this a change in the Internal Threshold? In a way this would be the inverse of the way the F75 adjusts sensitivity according to Mike Hillis. Regardless, it is a very good set up in difficult sites. Most NM users know about the difference in response speed between 89 & 90 Gain on 3DI. This is different. I had read about these steps in a forum post that quoted Alper of NM. I can't seem to find that post now that I want to re read it.