Multi frequency question

Pulltabby

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Does it cover more ground,go deeper,find smaller targets? Looking at chart seems covers more ground.How does detector unscramble so many targets on the 28 frequency chart?
 

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Pulltabby,

You are taking that chart/graphic too literally.

To your questions --

Cover more ground? No...that's more determined by coil size and swing speed.

Go deeper? Yes...possibly. Multi-frequency units generally deal with soil mineralization better (which allows more depth), and generally have better target ID on deeper targets, which means you might be more likely to dig the deep target since it might ID better on the multi-frequency machine than the single-frequency machine.

See smaller targets? No, not generally. Higher frequencies and smaller coils are generally better for finding smaller targets, and multi-frequency machines often include lower frequencies -- which may make them a bit less sensitive to the smallest targets.

As to your last question, about a "detector unscrambling so many targets," not sure what you are asking.

In a most basic sense, the advantage multi-frequency (specifically Minelab FBS technology, which is what I'm most familiar with) offers, is what I alluded to above. Better ability to "deal with" mineralized soil, and better target ID especially on deeper targets. Soil mineral is "dealt with" in a rather unique way, such that it is "kept separate" from target ID to a large degree. Then, with more than one frequency "seeing" any given target, the machine's algorithms compare the target information received from each frequency, and through this comparison (and with soil effects substantially "removed") a more accurate ID can be achieved, to greater depth (as compared to a single-frequency unit which only has one frequency with which to deal with both soil mineral AND target ID, and thus less accurate ID -- partially due to more soil mineral "contaminating" target ID on deeper targets).

Steve
 
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Fbs only processes 2 frequencies not 28.

Oh, boy, ghound! NOW you did it! :laughing:

I didn't want to open that can of worms here, and fry Pulltabby's brain!

You probably just lit the match that will veer this thread off into a ditch...! :lol:

Steve
 
Does it cover more ground,go deeper,find smaller targets? Looking at chart seems covers more ground.How does detector unscramble so many targets on the 28 frequency chart?

Do not be confused by the marketing hype. How many frequencies are transmitted into the ground is not important. The important parameter is, how many of those frequencies will the receiver section of the detector accept and process.

If your detector transmits 28 frequencies, but the detector only "listens" to two of the frequencies then, the other 26 frequencies are just a waste of battery energy.
 
Great explanation Steve. I've said it before and I'll say it again. I don't care HOW it works,I care THAT it works. I am an auto mechanic. I don't fry people's brains with how the CANBUS systems are set up or how variable valve timing works or some other thing...they want to know if their car is ready to drive. I want to know my FBS is ready to drive!:grin:
 
I thought that fbs recieves and processed 3 frequencies at once. Low me and higher and the noise cancel slected which frequencies to operate on

Sent from my SM-N950U using Tapatalk
 
Be it 1 frequency or 1000, in my ground the minelab machines are the only machine that are accurate with tone and id past 4 or 5 inches depth. For me it is essential. Oh yea, And the battery life is great for all those wasted frequencies wasting energy :D
 
The picture is a very bad representation of what is going. It doesn't matter the operating frequency of the detector. The search field always goes deep enough, even for the single frequency detector. A CTX-3030's search field will hit a 12" dime the same as a a low-end single frequency machine will. The biggest difference will be that the CTX-3030 is more likely to detect the very weak response field of the deep target than the low-end single frequency detector.

Multiple frequencies are most useful in target identification and counteracting conductive salts in wet sand. It won't get you more depth necessarily. You will get the most depth using a single frequency best suited to what you are hunting for with a slower swing speed. If silver coins are your game, low operating frequencies are what you want. If you want gold jewelry, higher frequencies are what you want. If you want relics, somewhere in between is a good compromise.

Maximum depth is best determined by how good your ground balance is, how good your coil null is, and how much of the signal you are whittling away by over-discriminating - and most important - how good your machine's signal processing software is. You do get depth bonus based upon frequency depending upon the metal you are looking for. You have a better chance of finding deep silver using a low frequency. This, however, is only a small component for depth compared to balance, coil null, and processor

Why does the FBS find the deep silver where other machine do not? It is mostly due to the machine's signal processing software - which is really, really good.
 
Agree with most of this except the low freq for silver, it's dependent on the size of the silver, big silver is a high conductor, small thin silver is a much lower conductor and is better found with higher freqs.
The detector has no idea what the metal is made off.


The picture is a very bad representation of what is going. It doesn't matter the operating frequency of the detector. The search field always goes deep enough, even for the single frequency detector. A CTX-3030's search field will hit a 12" dime the same as a a low-end single frequency machine will. The biggest difference will be that the CTX-3030 is more likely to detect the very weak response field of the deep target than the low-end single frequency detector.

Multiple frequencies are most useful in target identification and counteracting conductive salts in wet sand. It won't get you more depth necessarily. You will get the most depth using a single frequency best suited to what you are hunting for with a slower swing speed. If silver coins are your game, low operating frequencies are what you want. If you want gold jewelry, higher frequencies are what you want. If you want relics, somewhere in between is a good compromise.

Maximum depth is best determined by how good your ground balance is, how good your coil null is, and how much of the signal you are whittling away by over-discriminating - and most important - how good your machine's signal processing software is. You do get depth bonus based upon frequency depending upon the metal you are looking for. You have a better chance of finding deep silver using a low frequency. This, however, is only a small component for depth compared to balance, coil null, and processor

Why does the FBS find the deep silver where other machine do not? It is mostly due to the machine's signal processing software - which is really, really good.
 
Agree with most of this except the low freq for silver, it's dependent on the size of the silver, big silver is a high conductor, small thin silver is a much lower conductor and is better found with higher freqs.
The detector has no idea what the metal is made off.

Fair point. I have no experience with small, hammered coins, and given the frequency in which they are found in my neck of the woods, I tend not to consider them. I suppose the closest I would get is a US three cent piece, which is pretty small and thin.
 
Does it cover more ground,go deeper,find smaller targets?

In my test garden, which is matured for 2 years, I have found the following with my V3i.

On 6 inch coins Nickle, dime and quarter in the coin and jewelry mode running 3 frequencies it hits and ID's all three no problem.

On the 8 inch I can tell there is an object there in 3 frequency but not a good repeatable signal. If I switch to the lowest frequency, the dime and quarter hit strong and repeat about 75% of the time. The nickel almost disappears.

If I switch to the highest frequency the nickel comes in pretty strong and the dime and quarter id drops to less than half.

The Deep Silver program on the V3i runs only the 2.5kh frequency and it does hit deep. I can easily pick up a 10 inch quarter in the test garden.

Where the multi frequency machines shine is in salt water and mineralized soil. The V3i runs great on wet salt beaches....just don't take it for a swim.:laughing:
 
On the 8 inch I can tell there is an object there in 3 frequency but not a good repeatable signal. If I switch to the lowest frequency, the dime and quarter hit strong and repeat about 75% of the time. The nickel almost disappears.

This is the main reason to always run in stereo-mixed mode if your headphones support it. The AM channel will almost always pick a coin up in this situation, where as the DISC channel may produce a choppy signal, or no signal at all. I have pulled several 9+ inch dimes since I got my V3i, and the only reason I knew they were there was because the AM channel noticed.
 
ok now you guys are making sense to me ,i only hunt salt water beaches and i appreciate the stability of my cz21 in the wet sand but for dry sand and super black sand dry sand the multi freq detectors seem so much slower and less accurate than my single freq detector [at pro] ,my point being other than the ocean what are the advantages of multi freq
 
ok now you guys are making sense to me ,i only hunt salt water beaches and i appreciate the stability of my cz21 in the wet sand but for dry sand and super black sand dry sand the multi freq detectors seem so much slower and less accurate than my single freq detector [at pro] ,my point being other than the ocean what are the advantages of multi freq

A multi frequency detector will do a better job with target ID than a single frequency detector will. It will also be more stable in heavily mineralized soil and on wet sand. As good a detector as the AT Pro is, I can guarantee that my V3i is not slower, and is way more accurate. In dry sand, I hunt in straight up All Metal mode. My single frequency MX Sport does pretty good in the wet sand, but, if sensitivity is over 5, it will scream when the coil is submerged in salt water. My V3i does not (but, I do try to keep it out of salt water, as it isn't waterproof)
 
No, only 2 frequencies, 3khz and 25khz, the noise cancel only moves these very slightly to avoid emi, this was worked out by some smart tech folk, not myself !
Running 3khz is probably why it's hot on milled silver coins.


I thought that fbs recieves and processed 3 frequencies at once. Low me and higher and the noise cancel slected which frequencies to operate on

Sent from my SM-N950U using Tapatalk
 
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