Detector Frequency's

[foreign object]

Hope this finds all you guys and your familys doing well this holiday season. Lets all try not to forget those that are less forunate than us.

I have a question about frequencys.
Are there different frequencys that excell at finding different objects / different sizes and depth.
In short what would be the prefered frequency for
Coins
Gold jewerly/rings
Relics

Any info is appericated.
Thanks
Foreign

 

[khouse]

In general lower frequencies tend to hit higher conductive targets (silver) and go a little deeper. The higher frequencies tend to hit lower conductive targets (gold) and tend to be not as deep. Most coin and jewelry machines run from about 2.5 to 20 KHz. It seems that the average c&j machines are in the 5.9 to 18.75 range currently. Most manufacturers will list the capabilities of each machine. Use this as a guide.

 

[skookum]

Well almost.
My Fisher 1270 loves iron.
This has an even lower conductivity than gold and the 1270 operates on a rather low frequency of around 8 kHz.
Higher frequency detectors do tend to pick up minute particles (flour gold / tiny flakes) a bit better than the low frequency detectors which on the other hand tend to pick up bigger nuggets at more depth.

Just what I have read so far - cause I have never found either flour nor nuggets here in Germany.
HH
skookum

 

[vx3 man]

Get a V you get 3, 22.5 7.5 2.5. It like a whole new machine when you hunt in single frequency. I don't do it that often cause u can't compare the 3 and see what frequency is hitting hardest

 

[Critterhunter]

Rule of thumb (but not hard and fast rules) I always went by is that machines below about 8khz tend to hit harder on silver/copper coins, penetrate ground minerals better, and run smoother (for me here). I know in my soil that's true. Every machine I've owned or used above about 8khz in a single frequency machine was unstable and didn't get very good depth *in my soil for me*. Others may differ of course.

I always went by the rule of thumb that machines in the 14 to about 22 or 24khz range or so were more sensitive to fine gold (like small earings or thin chains). I've owned single frequency machines with higher frequency and, besides the poor depth *in my soil* on old coins (silver/copper) and trouble they had with my minerals (my soil ranges low to higher minerals depending on the site), I didn't care for them hitting small flakes of foil so well that I would chase those targets thinking they might be a piece of jewlery. I prefer those kinds of tiny bits of junk to sound sick and not hit well. Only thing I much care for hitting well when hunting for gold is rings, and because a ring is an intact metal loop even a super thin one will bang hard like a coin at depth for me. Only place I might want to chase down finer gold than rings is perhaps at the beach or in the water, but most days even there I'm only after rings myself as IMO that's what is mostly lost anyway, at least on the beaches I hunt.

Many believe certain frequencies will also penetrate certain minerals better than others. There's a name for this but it escapes me at the moment. That's one of the beauties of multi-freq machines, as you can be sure at least a few frequencies are probably going to punch deep at a given site. But in general lower freqs I always felt (and read) tend to punch deeper than higher ones. One of the reasons I liked the low freq Whites units of yesterday (QXT, 6000, etc)...And they also seem to run smoother in my soil and discrimination seems better, with more telling traits on target qualities via the audio.

Again though, these are not hard and fast rules. Some machines seem to defy the guidelines based on frequencies and what they should or should not be good at based on those.

 

[foreign object]

Thanks for the replies guys. I am getting a better feel/understanding on the different frequency's and how they apply to metal detecting.
Critterhunter you got me to really thinking about the requirements for my next detector.Thanks

Thanks again guys
foreign

 

[BarberBill]

While most of the above replies are pretty much accepted fact and no doubt can be shown in controlled tests, IMHO for nearly all coin and relic hunting most of us won't see much appreciable diffference in the field using the typical detector that runs from around 6 hz to 15-18 hz. That's why most general use detectors are manufactured in the 6 to 12 or 14 range. I'm not arguing that for specific purposes such as gold prospecting that the high to very high frequencies used there don't make a difference becaust they do. However, that makes most of them a poor choice for general detecting. Knowing your detector, using a coil that matches the conditions and persistence are more important in my view than whether the detector is running 10 hz or 14 etc. If one specific frequency was clearly superior, all manufactures would be designing their detectors around it.
My two bits.
BB

 

[Goldstrike]

I am not that much of a 'techi' kind of guy but using my logic only, I have always wondered the following......
Minelab utilises FBS (full band spectrum) technology which utilises or operates between 1.5KHz-100KHz so surely it would be a much greater advantage over machines that only operate or are limited to 1 or 2 specific frequencies? Although Minelab has patents on that technology, surely other companies could come up with similar technology that operates over a wide range of KHz and not just a few?
Some detectorists would say "but I only want to hunt for coins, or relics, or gold nuggets, or silver etc; but why not have a machine from the get-go that has the capacity to detect all of these targets?
The only reason I can come up with is that metal detector manufacturers purposely make different machines with limited capabilities making the consumer purchase other machines.
Most of us don't buy a metal detector just because it looks pretty or because of the paint job! (although that plays a small part) so it's not like a car purchase where we buy largely (but not solely) on aesthetics, we usually buy an M.D. because of it's metal detecting capabilities! So again, an FBS M.D. should detect anything that is detectable between 1.5KHz through to 100KHz which is anything any detectorist would want to detect!
The only other thing I would add is I do realise there are many other refinements i.e. multi tones, display layout, iron mask etc; etc; on different detectors but I'm only addressing the original KHz/frequency question that was originally posed by 'foreign object'.
I am still on that learning curve like most of us so what am I missing?

 

[Ism]

I am not that much of a 'techi' kind of guy but using my logic only, I have always wondered the following......
Minelab utilises FBS (full band spectrum) technology which utilises or operates between 1.5KHz-100KHz so surely it would be a much greater advantage over machines that only operate or are limited to 1 or 2 specific frequencies? Although Minelab has patents on that technology, surely other companies could come up with similar technology that operates over a wide range of KHz and not just a few?
Some detectorists would say "but I only want to hunt for coins, or relics, or gold nuggets, or silver etc; but why not have a machine from the get-go that has the capacity to detect all of these targets?
The only reason I can come up with is that metal detector manufacturers purposely make different machines with limited capabilities making the consumer purchase other machines.
Most of us don't buy a metal detector just because it looks pretty or because of the paint job! (although that plays a small part) so it's not like a car purchase where we buy largely (but not solely) on aesthetics, we usually buy an M.D. because of it's metal detecting capabilities! So again, an FBS M.D. should detect anything that is detectable between 1.5KHz through to 100KHz which is anything any detectorist would want to detect!
The only other thing I would add is I do realise there are many other refinements i.e. multi tones, display layout, iron mask etc; etc; on different detectors but I'm only addressing the original KHz/frequency question that was originally posed by 'foreign object'.
I am still on that learning curve like most of us so what am I missing?

Minelab FBS and BBS don't excell at finding small gold. There are trade offs with every tech.

 

[Elton]

Excellent post.............. I too have always read, and found lower works better on Silver & Copper...

 

[Roscue2]

Another note, as was already said, some machines have the ability to significantly change their frequencies. Others can change their frequencies slightly, such as the At Pro.

HH and GL

 

[SpiritRelic]

You can look up George payne,The inventor of vlf technology .He has a engineering paper written up somewhere here on the net that discusses this very subject.Some manufactures like to stay with one frequency.Multi frequency detectors have a large battery drain due to the number of frequencies.It seems multi frequencies can cut ground minerialazation way better than one.Like the sovereign for example.Look how popular it is for hunting the wet salt beach sand. :-D

 

[woodchiphustler]

This is why the Deus is so impressive. It can handle most situations .