randy
Forum Supporter
I think the metal detector companies need to seriously address EMI with better coil design and shielding, because the so called "noise reduction" feature on detectors does almost nothing. It does nothing on my Simplex, Vanquish, or Legend. It does nothing on videos I've seen with the Nox and the D2 as well.
How would you pass the TX/RX but shield the random noise at the same frequency? Perhaps there is a way, but to me, it seems common sensical that it has not been done yet, at least for consumer level machines.
As for "noise reduction", it certainly works on the E-Trac. I don't make videos, but I have proven this to my satisfaction on wild targets by running thru each channel on the same iffy target. Of course, I only have to prove it works to me, since I have no incentive to sell E-Tracs or other machines with noise cancel channels.
As a global example, around here, channel 11 on the E-Trac is usually way too chatty, with lots of high tone blips. Much more than any other channel. There is one site I could only hunt using channel 6, regardless of the channel it chose. I just manually set it to 6. I have many more examples of this with the E-Trac in my notes.
Now, I noise cancel with the coil on the ground, not in the air as they recommend, so it could be mineralization rather than EMI. Who knows, and who cares, as long as the silver keeps flying out of the ground. I don't have a 'scope, so I don't know if "SMF" is a wide range of VLF frequencies in the ranges we are talking about, and noise cancel shifts them a bit, or if it is really a single frequency with a bunch of harmonics. Of course, ML won't tell you, and the online discussion of this seems to be all speculation.
But, one of the reasons the E-Trac works so well as you set response "long" or sizing pinpointing or whatever it is, and you can tell a coin-sized target from EMI (at least I can), so I can run the machine hot and get away with it. I don't like machines that don't have this; hopefully the Manticore will, and I won't care.