ADVANCED TRAINING

Yeah I understand that but what's the correct way to noise cancel? 12" off of the ground, on the ground, or at let's say hip level with the coil vertical or horizontal?

Thats always been the question with FBS machines. We did kind of figure out that near the salt water the Exp liked channel 1 where as the ET/CTX liked channel 11 for the best depth. So how did those random freq shifts affect things....... especially with auto GB? I know a lot of guys just set the coil on the ground did the noise cancel and moved out smartly. I was one that did mine at the same heights i detected. The Nox seems to be a different kind of beast....... stand in one spot and you can get several responses. We know EMI changes..... id dare say more than the ground. Tom seems to be explaining the better method to do it with the Nox and the way it operates. But i feel the FBS has a better GB and noise cancel.

So, if per NASA-Tom's explanation we are to hold the Equinox off the ground, with coil vertical, and noise cancel that way, would it not make sense to noise cancel the CTX the same way? Though the machines are indeed different (Multi-IQ vs. FBS), I would think that given NASA-Tom's explanation, about EMI, earlier in this thread, that would indicate that the noise cancel method he described (coil vertical, off the ground) would make sense, and thus apply, for any machine?

Steve

But the Nox to me is a more sensitive machine to interference. Reading Andy Sabisch’s book he said each manual of FBS had how to noise cancel different. He said it should be done often through out a hunt. He says since you are searching for buried targets the correct method is to rest the coil on the ground. Apparently to factor in ground feed back as well as outside interference seen by the coil which is what the detector will see when you are hunting.

dewcon4414 --

Understood. However, I do not agree with Andy, about "ground feedback." "Ground feedback" is not "EMI," unless by "ground feedback" he means something coming from a buried electric line, underground dog fence wire, etc. Otherwise, "ground feedback" as we usually refer to it -- mineralization "contamination" within the Rx signal -- is NOT, unless I am totally misinformed, mitigated by initiating a noise cancel. It's ONLY mitigated through adjusting ground balance. But mitigating "ground feedback" by noise cancelling? I think Andy is wrong about that...

Steve

Maybe Steve.... but it is selecting a combo of freqs to compensate for EMI which surely affects depth. I’m not certain that noise cancel is just eliminating EMI. Otherwise they might have called it EMI cancel. Also I’m NOT swinging my coil chest high so it makes a lot more sense to set it on the ground or near swing height. Otherwise the conditions are different. Or if there is no difference in what the coil hears either way.... then why do it? Why woul I want to compensate for EMI that may not affect hunting....but chest high more certainly will in the freq it choices. I do know channel selection made the difference on the Explorer when we manually selected the channel for certain conditions and DIDNT noise cancel. Most of the time when we noise canceled ..... it would fall in that mid range.



Edited 1 time(s). Last edit at 01/25/2019 08:46PM by dewcon4414.