Frequency in metal detecting

woodbutcher

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I've googled and read hundreds of threads on this subject.And although some are different the majority are the same.The majority states that 15 kHz for gold jewelry, 10kHz and under for copper, silver and gold coins.
I've always wondered am I missing coins by not having a 3kHz coil and by majority vote the answer is no...Anything under 10 kHz seems to be good for coins.Not to say higher frequency won't find coins,cause they will.But it seems 10kHz and under are preferred for coinshooters.
I liked my prior fbs units,but they weren't my favorite for my hunting.Very well built,the best I've owned.And I would put minelab on the top shelf for coinshooting, along with others.I just read so many threads that fbs units push out frequency as high as 100kHz,I can't figure out why they won't pick up gold chains if that's true.In air test mine wouldn't,even rubbed on coil.But for coinshooting the fbs are hard to beat.
And the majority I've read state to get a coin machine for coins,and a jewelry machine for jewelry. Although some machines are good at both,none excell at both.Makes sense why so many own the Etrac and At pro together.
I have notices the machines I have ran at 3 kHz were quiet and ran very stable.Change the frequency to 14 and above the same machines read more tiny targets and weren't as quiet. Most gold rings will be picked up at 3 kHz though,no chains though,and most detectors aside from the At pro will not register gold chains.From my experience.
If I can continue this hobbies later in the year I think I will be running 3 kHz for good,just seems to be very stable and doesn't read every piece of foil etc. I could miss gold chains but that's ok,I'll save that part of hunting for places like swimming holes and parks.
 
Big myth about frequencies

Yes, the higher frequencies get the gold and the lower get the silver. Funny thing is that an electronics buddy of mine said the Minelabs only run 1 frequency at time but will change for various reasons (1-100 kHz). Personally, I have handled a T2 that was digging CW bullets at almost a foot where the SE Pro did not even chirp. I have seen an ACE 250 operate in an iron infested sight and get goodies where an MXT didn't find a thing. I think it is more of the detector and coil design that will give you the best performance and who is operating it and how much time they have on the unit...
 
This is one question I didn't even know to ask when purchasing my first detector. Any newbie like me should be following this post for sure, just to understand that there are differences out there for a reasons. I got lucky purchasing what I would have wanted without even knowing it, a DFX (hope that makes sense). I look forward to a good discussion on this topic!
 
This is one question I didn't even know to ask when purchasing my first detector. Any newbie like me should be following this post for sure, just to understand that there are differences out there for a reasons. I got lucky purchasing what I would have wanted without even knowing it, a DFX (hope that makes sense). I look forward to a good discussion on this topic!

I probably already told you this in another thread but if you do not have the book Digging Deeper with the DFX get it. Read it slow and multiple times.
Explains why 3kHz finds more coins and why 15kHz find the low conductors well. Has to do with the ground VDI number and how the different frequencies react to iron mineralization as well as where the raw VID numbers for a high conductor reside in reference to the ground VID numbers per frequency.
In short 3kHz works better in high iron mineralization and 15kHz works better in low or conductive mineralization. The book has charts that explain it better than words do.. Cool thing is the DFX will let you determine what the mineralization is, and to some extent how much and then you can decide which frequency will work better for what you are targeting...
Sorry to go off on a tangent.. trying to solidify what I have read.. attempting to explain can help you figure out if you remember! :shock:
 
I probably already told you this in another thread but if you do not have the book Digging Deeper with the DFX get it. Read it slow and multiple times.
Explains why 3kHz finds more coins and why 15kHz find the low conductors well. Has to do with the ground VDI number and how the different frequencies react to iron mineralization as well as where the raw VID numbers for a high conductor reside in reference to the ground VID numbers per frequency.
In short 3kHz works better in high iron mineralization and 15kHz works better in low or conductive mineralization. The book has charts that explain it better than words do.. Cool thing is the DFX will let you determine what the mineralization is, and to some extent how much and then you can decide which frequency will work better for what you are targeting...
Sorry to go off on a tangent.. trying to solidify what I have read.. attempting to explain can help you figure out if you remember! :shock:

I am planning on it. Thanks
 
Yep, but a bit more painful on the old wallet than a used DFX! ;-)

Very true but it's all in what you are willing to dedicate to your hobby. A good DFX is in the neighborhood of $450 - $600 you can find a used V3i for ~$800 I have seen them go as low as $750 or as high as $1500 with accessories. They are both excellent machines.
 
I probably already told you this in another thread but if you do not have the book Digging Deeper with the DFX get it. Read it slow and multiple times.
Explains why 3kHz finds more coins and why 15kHz find the low conductors well. Has to do with the ground VDI number and how the different frequencies react to iron mineralization as well as where the raw VID numbers for a high conductor reside in reference to the ground VID numbers per frequency.
In short 3kHz works better in high iron mineralization and 15kHz works better in low or conductive mineralization. The book has charts that explain it better than words do.. Cool thing is the DFX will let you determine what the mineralization is, and to some extent how much and then you can decide which frequency will work better for what you are targeting...
Sorry to go off on a tangent.. trying to solidify what I have read.. attempting to explain can help you figure out if you remember! :shock:

You can see an excellent explanation of that concept in Part 8 of this DFX video, starting at the 3:54 mark. Continues into Part 9 video.

https://www.youtube.com/watch?v=87PLmK7wv28

Papa
 
You can see an excellent explanation of that concept in Part 8 of this DFX video, starting at the 3:54 mark. Continues into Part 9 video.

https://www.youtube.com/watch?v=87PLmK7wv28

Papa
Thanks I will watch that again!
I don't remember that but it as been a few weeks since I watched it and not since I started reading DD.

YEP, that made perfect sense and I understood everything he was saying after reading it. I do recall that from the first time around but this time it makes complete sense.
 
Just get a BBS, FBS, or FBS2 machine and stop worrying about it. After all, what do you plan to do, go over a search area 2 or 3 times each in a different frequency? I've always believed in no more swings than necessary. And while I do cover an area multiple times if I am actively searching for something, first pass, then second pass at 90 degrees and third pass at 45 degrees, I am swinging in different directions each time.

3 PASSES.jpg
 
I have many hours using a 5.9 kHz F2...a 12 kHz Compadre...a 13 kHz F70 and a 14.5 kHz Vaquero.
I have found silver coins, silver jewelry and gold jewelry with all of them.
I have found more gold jewelry with the lowest frequency detector, the F2, than any others simply because I used it more.
I tend to find more silver coins deeper with the higher frequency F70 than the rest because it is more powerful than the others, (except maybe the Vaquero), but more probably because I use it at more sites where deeper older silver is more likely to be found.
I have tested the F2 on small gold and a tiny and thin gold chain and it seems to pick them up fine with the sniper coil.
Not super deep but well within shallow ranges where I have found over 30 gold targets so far.
I have read many posts where hunters have found silver coins super deep, way deeper than I ever have near the one foot level with higher frequency detectors like the F70 and the F75.

I suppose in special situations frequency can matter.
High frequency for nugget hunting, low frequency for deep silver in certain situations, but for the kind of hunting I do for the normal coin and jewelry targets I look for in all the type of sites I spend my time I never worry about frequency...it never has even entered my mind.
I pick and use detectors and different coils for different sites more often than not because of ease of use and the fun factor which is more important to me in this hobby and why I do this.
Maybe ignorance IS bliss in my case...I still seem to have been more successful in my short 5 year career than I ever thought possible when I started.
 
You will find coins with any frequency the lower frequency tend to go deeper into the soil. the higher the frequency the better it will high on smaller gold
 
Bottom Line Up Front (BLUF): I have an AT Pro and an Omega (check the operating Fq's), the AT Pro is my go-to for many reasons....the Omega is a coin killer....but.....all I'm saying on this thread....
 
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