etrac noise cancel

[rbholt80]

All the research iv done to get a new detector has been useful.
I found a guy testing the frequency emitted from the etrac coil.
It was only 1 frequency but raised and lowered as he changed the noise cancel.
That made think about low conductor items being picked up better with higher kHz signals.
So looks to me if you want smaller gold items run the noise cancel high cause that's when the coil is emitting a higher frequency.
If u want deeper silver run the noise cancel very low.
Fbs seems to use harmonics of whatever frequency your running to just help with vdi information and discrimination

 

[Dan(NM)]

I read that somewhere before, the guy had a chart showing the frequency each number was operating at. I cannot remember where I found it.

 

[rbholt80]

Well it will be helpful just to know what's going on so you can adjust it for what your after while hunting.

 

[IDXMonster]

I also understand that a noise cancel should be performed when you arrive at a site no matter what. It's common to noise cancel when we hear the detector making noise or the screen is erratic,but just because it may not be doing these things doesn't necessarily mean that there isn't EMI present, negatively affecting the stability or performance of the machine. How much of a difference it all makes in performance has yet to be thoroughly quantified,as far as I know...but personally I'll trust the engineers at Minelab on this.

 

[rbholt80]

Well then I guess having the abilities to change it manuely was pointless for those engineers to include.
Thank you I'll never think critically again and question or investigate anything.

 

[masterjedi]

The Etrac is an FBS machine. It runs frequencies from 1.5khz to 100khz all at the same time. That is why the target ID is so great!

 

[rbholt80]

That's what we all thought. That's not exactly how it works. It runs only 1 but uses harmonics of that 1 to help with things.
There isn't a true multi simultaneously freq detector out yet.

 

[Dan(NM)]

It's not effectively running at 100 Khz, it sucks on raw gold nuggets. Straight 15khz machines will smoke the Etrac on small gold. I own an Etrac now and have tested small nuggets with it using small coils and I tested a Fors Gold when I owned one, the Fors had no problem picking up my test nuggets, the Etrac, not a peep.

 

[rbholt80]

Yep its base freq is about 15khz and lowers down to about 5khz at the low end. The vid and info I found showed all this.

 

[Dan(NM)]

The chart I saw showed only a very small shift in the frequency with each adjustment on the manual noise cancel selection.

 

[rbholt80]

Can't find the info now but I have a link to a guy who has done some testing in the field etrac noise cancel test.

 

[rbholt80]

Yea its only about 400 hz at a time. I can't remember the exact range but its from around 5khz to about 15khz. Some place in that range

 

[IDXMonster]

Well then I guess having the abilities to change it manuely was pointless for those engineers to include.
Thank you I'll never think critically again and question or investigate anything.

You're welcome!
The article you linked to had not a shred of proof of any kind to back up what he was saying. If you follow DanNM's advice there is a video with operating equipment showing the frequency shift from channel 1-11 is minimal,certainly NOT a 10khz spread. It's not enough to even consider changing it.
I don't know why the engineers allow the user to change NC,perhaps as a last resort. It's CERTAINLY not intended to select frequencies,though manual selection of channels allows the user to do just that with a minimal effect. I would further assume that machine stability is more critical to find deeper targets than a 1-1.5 kHz shift in frequency.
I'll try to post a link to the video if I can find it,then you can draw your own conclusion.

 

[rbholt80]

Whatever you want to do. Stick with factory. Just cause your scared to a temp better things doesn't mean that others are willing to follow the heard off the cliff. Ttyl sheep

 

[IDXMonster]

Of course we can do whatever we want as far as trying different adjustments go. But it many cases unless HARD EVIDENCE backs something up we can find ourselves back at square one or worse,because we didn't believe our predecessors and their many years of experience. I don't have but 5 years of experience with metal detecting. At NO point in this hobby have I run across a situation where I tried something "out of bounds" that turned out to be beneficial,i.e. better than what the detector manufacturer or people before me had figured out. As always,good luck and if you find that you CAN repeat a test showing the shift benefit when it comes to depth or finding something specific,please post! We are all after that elusive "deeper coin".

 

[rbholt80]

The info is only there to give an idea to those who want to try things and see for them self. I dont need to convince anyone about freq and detection. Many companies have already shown that there is s huge collation between depth and size and type of metal versus freq. Im not going to argue im not going try and persuade you or anyone. But i will give out info on how something works for those who are not sure or are blinded by sales propaganda and language used to sell a product. Iv had my etrac from the begging when they came out. I love that detector like no other iv used in 29 years of detecting. But its no wizard with magic technology and it can be pushed harder than factory setting and there is a gain in a lot of cases but not all. Even I have to run auto sens sometimes and let noise cancel find its own happy spot but seldom.

 

[surfchunker]

boy this thread is a piece of crap, it runs 3 frequency's at once and I never noise cancel and run either channel 6 or 9 ... I read it on the internet so it must be true crap

 

[sprchng]

All the research iv done to get a new detector has been useful.
I found a guy testing the frequency emitted from the etrac coil.
It was only 1 frequency but raised and lowered as he changed the noise cancel.
That made think about low conductor items being picked up better with higher kHz signals.
So looks to me if you want smaller gold items run the noise cancel high cause that's when the coil is emitting a higher frequency.
If u want deeper silver run the noise cancel very low.
Fbs seems to use harmonics of whatever frequency your running to just help with vdi information and discrimination

http://www.minelab.com/usa/treasure-talk/e-trac-manual-versus-auto-features-for-expert-users

 

[masterjedi]

ya, we would like to see proof of an Etrac only running on 1 frequency at a time. rbholt80 ... you are up sir ...

 

[IDXMonster]

Geotech [ PM ]
Re: Noise Cancel Frequencies
February 03, 2012 08:15PM Registered: 4 years ago
Posts: 76
> On noise cancel 1 there’s a burst of pulses every 0.72ms (1.39KHz) and each pulse has a rate of 45 us (22.2KHz)
> On noise cancel 11 there’s a burst of pulses every 0.6ms (1.67KHz) and each pulse has a rate of 36 us (27.78KHz)

I don't recall the numbers, but these seem perfectly reasonable. There is about a 20% variation over the noise cancel range or, if you take a midpoint (Noise Cancel 6), about +/- 10%. As I mentioned in another thread, the nominal high frequency is 25kHz (which you see as the 8 high pulses) and the nominal low frequency is 1/8th of that, or 3.125kHz, which you see as a single large pulse. That's all; there are only 2 frequencies. Noise Cancel slightly shifts everything, but not by enough to make any difference on target sensitivity.

The above only is quoted from the Dankowski forum,hope I don't catch hell for it...
I was mistaken about the shift,I found the video testing the EXPLORER but,the eTrac MAY be different. The range was Noise Cancel 1 winding up at 16.1 kHz and Noise Cancel 11 winding up at 12.8 kHz. So,on the EXPLORER,the kHz numbers went DOWN as the Noise Cancel channels went UP. There may be a slight advantage to manually choosing channels depending on the target,just so long as the channel chosen doesn't have EMI,which would effectively either hamper detection of a target or perhaps just make it a "wash".
Bottom line is...I think a stable/semi stable machine is more effective. Making it stable from site to site is easiest for me using the noise cancel function. Can it be done differently? Absolutely. To do what works FOR YOU in YOUR sites is what SHOULD be done,and the FBS machines give us the ability to work it any way we choose.
To find the video,since I can't link it,go to YouTube and search for "Minelab Explorer". The video title is "Getting the most depth from your Explorer" or something close,it should be one of the first ones listed. There's a Part 1 and Part 2 if anyone thinks they'll do them any good...
Have fun!