FoRs Gold.

Round 2
http://australiangoldfields.freeforums.org/post20438.html#p20438

Good hands on review Narrawa.

Had a little bit of a play around with the Nokta fors gold today, thanks Narrawa, seems to be a good little well balanced and comfortable detector to use.

Only had it going in the park and testing it on a few different coins and some ferrous and non ferrous pieces of metal targets, you could easily get it to discriminate out ferrous junk targets, a 5cent coin and a nail, and still easily picking up the $2 coin which was hitting at 82 on the flat side as well as on its edge running parallel with the coil, it was a bit confused on its edge with the coin running at 90° across the coil, numbers were fluctuating a bit.

All in all it seemed to be a good little machine for the price.

cheers dave

Just to add to that above...anyone in the Dubbo region who wants to take a look at the Fors Gold, PM me and we'll work something out. Im in Dubbo ATM.

Thanks Narrawa for the review and comparison between the other detectors.
Out of the detectors that you compared which would you pick up first to look for gold in say trashy mullok heaps?

Hi Narrawa,

I notice a vdi of 82 and 82 for $1 ,$2 coins which is the same as aluminium screw caps. It dosen't look good with the fors to be able to seperate. Not like the v3i which the screw caps are no problem. Maybe the Racer might have something up its sleve to seperate.

Regards Pinpointa.

Pinpointer,
Iv found many a screw cap, ring pull and twist top thats been disfigured, and thought i was digging a coin or ring. World wide im betting others have found the same with the v3i. Its not immune to the amount of other metals that read the same as our, and other countries coinage and jewelry.

Iv read posts and heard people tell me they saw a demo of this that and the other make/model disc out a rusty nail while atop/below a coin. Thats something iv done on many occasions just to see the out come. Iv also manipulated the nail/coin so the detector continues to see either one. As an example, it was done the other day when Davesgold was here and the v3i made me look like a goose when conducting a quick test over a bent rusty nail and a $2 coin atop the ground. Lose the nail and lose the coin...Yet iv dug many situations where in the ground the complete opposite was the effect....if not for the pin-pointer id have not know the nail was even there on some digs using certain patterns.? If we had more time i could have shown him a cherry picking pattern that reports on only our coins, or just 1-2$ coins....but i guarantee i'll dig a few cap assortments with those patterns.

The v3i is a handful of detector there's no argument there, but in the real world, its just another detector with lots to play with. Having said that, i love it, and would only get rid of it when something like it is PC programmable.

As for the racer, it doesn't really have to offer much in the way of performance over other makes and models. It only needs to compete.

Aurumpro,

Out of the detectors that you compared which would you pick up first to look for gold in say trashy mullok heaps?

To answer that just quickly...id pick the FG. Why you ask when the others have the runs on the board.?....Depth.

As to a conductive halo around any non-ferrous object, there is no evidence for this being able to affect a PI, even if it did exist. Most good PI's nowadays have a conductive shield around the coil to minimise capacitive effects with the ground.

I was always a strong believer in the Halo effect, but after reading a few reports on it, and the effects in which its suppose to effect a metal detector....i reserve the right to be skeptical, and have mixed emotions re this subject.
To add a little more to what one must take into consideration re PI detectors is this.......porous gold, specie gold, sponge gold whatever you want to call it....the sort that gives zip signals to a PI, yet can only be detected by VLFs. Iv seen it, held it.. and was baffled by it. Now think about the ability of the GPX range of detectors that are able to "not" see certain metals that are very decayed.? These metals in this state still stick to a magnet...but give zip signal on the GPX range...this iv seen and have shown others. Now, hows the halo effect looking if these models are able to "filter" out a metal that is actually something you can physically hold. Anyone ever picked up a halo effect.?...perhaps someone has a picture of one.?  
Im not saying there isn't anything in it, because for many years i was convinced of its presence, or the presence of something that caused a nugget to appear larger than it really was.? Eddy currents flowing through particles and the skin effect on a substance called....
.....halounobtainable.<---new word.

There is just no way that any nebulous halo, of what can only be virtually non-conductive oxides or salts, gives any signal on a standard PI.
Maybe, the soil conductivity would be enhanced enough for an effect to be noticed with high frequency induction balance detectors, say the Goldbug 2 at 75kHz, but the jury is out on that one, as there are other soil effects at high frequencies that can be confused with a halo response.

Eric.F.

Im happy to sit on the bench with Eric with this one.



.

Thanks Narrawa I was going to buy one after your last reply to me but then the add for the GPZ7000 came out in the yankee prospecting mag.
I believe its release is imminent So I'll be putting my penny's towards that now.

All good mate, no need to explain to me the importance of having the new ML PI. I'll be getting one myself.

Just to cap off why i said depth to your question......from the outings iv had with the FG so far....depth at the end of the day makes all the difference. On more than one occasion it out performed the MXT on depth. And the MXT is certainly no slouch. But, in order to dig a target, you must be able to hear it first.

This should answer most of your questions re VLF and PI metal detectors.

From Whites Electronics. (Metal detectors)

Two types of metal detectors: VLF(Very Low Frequency) and PI(Pulse Induction)
Type 1: VLF (Very Low Frequency)
Transmitter
Inside the metal detector's loop (sometimes called a search head, coil, antenna, etc.) is a coil of wire called the transmit coil. Electronic current is driven through the coil to create an electro-magnetic field. The direction of the current flow is reversed several thousand times every second; the transmit frequency "operating frequency" refers to the number of times per second that the current flow goes from clockwise to counterclockwise and back to clockwise again.

When the current flows in a given direction, a magnetic field is produced whose polarity (like the north and south poles of a magnet) points into the ground; when the current flow is reversed, the field's polarity points out of the ground. Any metallic (or other electrically conductive) object, which happens to be nearby, will have a flow of current induced inside of it by the influence of the changing magnetic field, in much the same way that an electric generator produces electricity by moving a coil of wire inside a fixed magnetic field. This current flow inside a metal object in turn produces its own magnetic field, with a polarity that tends to be pointed opposite to the transmit field.

Receiver
A second coil of wire inside the loop, the receive coil, is arranged (by a variety of methods) so that nearly all of the current that would ordinarily flow in it due to the influence of the transmitted field is cancelled out. Therefore, the field produced by the currents flowing in the nearby metal object will cause currents to flow in the receive coil which may be amplified and processed by the detector's electronics without being swamped by currents resulting from the much stronger transmitted field.

The resulting received signal will usually appear delayed when compared to the transmitted signal. This delay is due to the tendency of conductors to impede the flow of current (resistance) and to impede changes in the flow of current (inductance). We call this apparent delay "phase shift". The largest phase shift will occur for metal objects which are primarily inductive; large, thick objects made from excellent conductors like gold, silver, and copper. Smaller phase shifts are typical for objects which are primarily resistive; smaller, thinner objects, or those composed of less conductive materials.

Some materials which conduct poorly or not at all can also cause a strong signal to be picked up by the receiver. We call these materials "ferromagnetic". Ferromagnetic substances tend to become magnetized when placed in the field like a paper clip which becomes temporarily magnetized when picked up with a bar magnet. The received signal shows little if any phase shift. Most soils and sands contain small grains of iron-bearing minerals which causes them to appear largely ferromagnetic to the detector. Cast iron (square nails) and steel objects (bottle caps) exhibit both electrical and ferromagnetic properties.

It should be pointed out that this discussion describes an "Induction Balance" detector, sometimes referred to as "VLF" Very Low Frequency (below 30kHz). This is the most popular technology at the present time, and includes the "LF" Low Frequency (30 to 300kHz) instruments made for prospecting.

Discrimination
Since the signal received from any given metal object exhibits its own characteristic phase shift, it is possible to classify different types of objects and distinguish between them. For example, a silver dime causes a much larger phase shift than an aluminum pull-tab does, so a metal detector can be set to sound off on a dime yet remain quiet on the pull-tab, and/or show the identification of the target on a display or meter. This process of distinguishing between metal targets is called "discrimination". The simplest form of discrimination allows a detector to respond with an audio output when passed over a target whose phase shift exceeds a certain (usually adjustable) amount. Unfortunately, with this type of discriminator the instrument will not respond to some coins and most jewelry if the discrimination is adjusted high enough to reject common aluminum trash for example pull-tabs and screw-caps.

A more useful scheme is what is called "Notch Discrimination". With this type of system, a notch in the discriminate response allows the detector to respond to targets within a certain range (such as the nickel/ring range) while still rejecting targets above that range (pull-tabs, screw-caps) as well as below it (iron, foil). The more sophisticated notch detectors allow for each of several ranges to be set for either accept or reject responses. White's Spectrum XLG for example, provides 191 individually programmable notches.

A detector may provide a numeric readout, meter indication, or other display mechanism which shows the target's likely identity. We refer to this feature as a Visual Discrimination Indicator, or V.D.I. Detectors with this capability have the advantage of allowing the operator to make informed decisions about which targets they choose to dig rather than relying solely on the instruments audio discriminator to do all the work. Most, if not all, V.D.I. detectors are also equipped with audio discriminators.

Metal detectors can distinguish metal objects from each other based on the ratio of their inductance to their resistivity. This ratio gives rise to a predictable delay in the receive signal at a given frequency. An electronic circuit called a phase demodulator can measure this delay. In order to separate two signals, such as the ground component and the target component of the receive signal, as well as to determine the likely identity of the target, we use two such phase demodulators whose peak response is separated from each other by one fourth of the transmitter period, or ninety degrees. We call these two channels "X" and "Y". A third demodulated signal, we call "G", can be adjusted so that its response to any signal with a fixed phase relationship to the transmitter (such as the ground) can be reduced to zero regardless of the strength of the signal.

Some metal detectors use a microprocessor to monitor these three channels, determine the targets's likely identity, and assigning it a number based on the ratio of the "X" and "Y" readings, whenever the "G" reading exceeds a predetermined value. We can find this ratio with a resolution of better than 500 to 1 over the full range from ferrite to pure silver. Iron targets are orientation sensitive; therefore as the loop is moved above them, the calculated numerical value may change dramatically. A graphic display showing this numerical value on the horizontal axis and the strength of the signal on the vertical axis is extremely useful in distinguishing trash from more valuable objects. We call this display the "SignaGraph"TM.



Ground Balance
As previously mentioned, most sands and soils contain some amount of iron. They may also have conductive properties due to the presence of salts dissolved in the ground water. The result is that a signal is received by the detector due to the ground itself which may be thousands of times stronger than the signal resulting from small metal objects buried at modest depths. Fortunately, the phase shift caused by the ground tends to remain fairly constant over a limited area. It is possible to arrange things inside the detector so that even if the strength of the ground signal changes dramatically-such as when the loop is raise and lowered, or when it passes over a mound or hole-the detector's output remains constant. Such a detector is said to be "ground balanced". Accurate ground balance makes it possible to "pinpoint" the location of the targets with a good deal of precision as well as to estimate the depth of the targets in the ground. If you choose to search in a non-discriminate, or "all-metal" mode, accurate ground balance is essential. The simplest form of ground balance consists of a control knob which the operator adjusts while raising and lowering the loop until good balance is achieved. Although this method can be quite effective, it can also be tedious, and some people find it to be difficult or confusing. More advanced detectors will perform ground balance automatically, typically by a two-step sequence in which the detector is balanced with the loop raised, then balanced once more with the loop lowered to the ground. The most sophisticated ground balance detectors will gradually adjust themselves as changes in the composition of the ground occur. We refer to this as "Tracking Ground Balance". A good tracking detector allows you to balance once, then hunt for the rest of the day without having to balance again. A word to the wise - many detectors which are advertised as having "automatic" or "Tracking" ground balance are actually factory preset to a fixed balance point. It's a little like welding your car's accelerator halfway to the floor and calling it "cruise control".

Motion/Non-Motion Modes
Although the ground signal may be much stronger than the target signal, the ground signal tends to remain the same, or change very slowly, as the loop is moved. The signal from the target, on the loop is swept over it. This opens up the possibility of using techniques to separate ground from target signals by looking at the rate of change of the receive signal rather than looking at the receive signal itself. Metal detector modes of operation which rely on this principle are called, not surprisingly, "Motion" modes. The most important example is a mode called "Motion Discrimination". If we wish to isolate the target signal well enough to determine the target's identity, the ground balance alone is not enough. We need to look at the target from a couple of different perspectives, sort of like the way distances can by measured by triangulation if you have more than one viewpoint. We can only be ground balanced from one particular "viewpoint"; the other will contain some combination of target and ground signal. Fortunately, we can use the motion technique to minimize the effect of the remaining ground signal. At the present time, all discrimination and V.D.I. detectors require loop motion to be effective. This turns out not to be much of a penalty in practice since you have to move the loop anyway in order to cover any ground.

Once you have located a target in the motion discrimination mode, you will probably want to more precisely locate it for easy recover. If your detector is equipped with a depth meter, you will also want to measure the target's depth. "Pinpoint" locating and depth measurement are done in what is called the "All Metal" mode. Since discrimination is not required to perform these functions, loop motion is not usually required - except for that motion required to get the loop over the center of the target. More precisely, the speed at which you move the loop is not important. The All Metal mode (also sometimes called the "Normal" mode, or "D.C." mode) is therefore called a "Non Motion" mode.

There are a few potential points of confusion here. Some detectors are equipped with a feature called "Self Adjusting Threshold", or S.A.T., which gradually increases or decreases the audio output in an attempt to maintain a quiet but audible "threshold" sound. This helps to smooth out audio changes caused by the ground or inadequate ground balance. S.A.T. may be very rapid or very slow depending on the detector and how it's adjusted, but strictly speaking, S.A.T. implies a motion mode of operation. This is why you will hear certain detectors referred to as having a "True Non Motion" mode; meaning, of course, an All Metal mode without S.A.T. Another sometimes confusing thing is that some discriminators allow for adjustment down to the point that the discriminator responds to all metals - in other words, it's a discriminator that doesn't discriminate. This is something very different, however, than the All Metal mode previously described. For this reason we often refer to it as a "Zero Disc" mode.

Microprocessor Control
A microprocessor is a complex electronic circuit which can perform all of the logic, arithmetic, and control functions necessary to build a computer. A sequence of stored instructions called a "Program" is performed by the microprocessor, one at a time, at a speed which can be as high as several million times every second.

The use of microprocessors in modern metal detectors has opened up possibilities which were undreamed of just a few years ago. In the past, adding new and useful features to a detector meant additional control knobs and switches. There were obvious limits to this approach; at some point size, cost, and operator confusion got out of hand. With a microprocessor, a liquid crystal display, and a simple keypad the problem is solved. A virtually unlimited number of features can be added without adding any additional hardware. These features can be arranged by a system of "Menus", so that anybody who can follow the prompts on the display can easily find the control they're after and adjust it to their liking. In this way, a single detector can be set up for just about any application, or to suit anyone's personal preference.

You might think that this sounds a little complicated - what if you don't want to be bothered with making all of those adjustments? Here's the real beauty of microprocessor control; you don't have to. Each control can be set to a typically useful position by the microprocessor each time you turn the machine on so the beginner or casual user never has to know that all those advanced features are there. Or better yet, you can select your preference from the menu - coin hunting, prospecting, relic hunting, etc. - and the microprocessor will make all of the adjustments for you choosing settings that have been proven in actual use by seasoned veterans.

In addition to these advantages, powerful software routines can be used to enhance the detector's audio discrimination capabilities and to display information in a variety of formats on an L.C.D. making the operator's job of interpreting target responses faster and easier.

VLF Summary
Although the modern high performance VLF metal detector has been several decades in the making, new advances will continue to be made. Better, smarter, easier-to-use machines will eventually be introduced. Today's very best detectors will not be easy to improve on but as long as there is treasure to be found, you can be sure that research is underway to take metal detecting technology to the next level.

Type 2: P.I. (Pulse Induction)
Transmitter
The search coil or loop of a Pulse Induction metal detector is very simple when compared to a VLF instrument. A single coil of wire is commonly used for both the transmit and receive functions.

The transmitter circuitry consists of a simple electronics switch which briefly connects the coil across the battery in the detector. The resistance of the coil is very low, which allows a current of several amperes to flow in the coil. Even though the current is high, the actual time it flows is very brief. Pulse Induction detectors switch on a pulse of transmit current, then shut off, then switch on another transmit pulse. The duty cycle, the time the transmit current is on with reference to the time it is off, is typically 4%. This prevents the transmitter and coil from overheating and reduces the drain on the battery.

The pulse repetition rate (transmit frequency) of a typical PI is about 100 pulses per second. Models have been produced from a low of 22 pulses per second to a high of several thousand pulses per second. Lower frequencies usually mean greater transmit power. The transmit current flows for a much long time per pulse, however, there are fewer pulses per second. Higher frequencies usually mean a shorter transmit pulse and less power however, there are more transmit pulses per second.

Lower frequencies tend to achieve greater depth and greater sensitivity to items made from silver however, less sensitive to nickel, and gold alloys. They typically have a very slow target response, which requires a very slow coil sweep speed.

Higher frequencies are more sensitive to nickel and gold alloys however, less sensitive to silver. They may not penetrate quite as deep as the lower frequency models regarding silver however, can be used with a faster coil sweep speed. Higher frequency models are generally more productive for treasure hunting because the faster sweep speed allows more area to be searched in a given time, and they are more sensitive to the ultimate beach find, gold jewelry.

As previously mentioned a typical PI search loop contains a single coil of wire which serves as both the transmit and receive coil. The transmitter operates in a manner similar to an automobile ignition system. Each time a pulse of current is switched into the transmit coil it generates a magnetic field. As the current pulse shuts off, the magnetic field around the coil suddenly collapses. When this happens, a voltage spike of a high intensity and opposite polarity appears across the coil. This voltage spike is called a counter electromotive force, or counter emf. In an automobile it is the high voltage that fires the spark plug. The spike is much lower in intensity in a PI metal detector, usually about 100 to 300 volts in peak amplitude. It is very narrow in duration, usually less than 30 millionths of a second. In a PI metal detector it is call the reflected pulse.

Receiver
Resistance is placed across the search coil to control the time it takes the reflected pulse to decay to zero. If no resistance, or very high resistance is used, it will cause the reflected pulse to "ring". The result is similar to dropping a rubber ball onto a hard surface, it will bounce several times before returning to rest. If a low resistance is used the decay time will increase and cause the reflected pulse to widen. It is similar to dropping a rubber ball onto a pillow. Since we are interested in having it bounce once critical damping for a rubber ball might be like dropping it onto carpet. A PI coil is said to be critically damped when the reflected pulse decays quickly to zero without ringing. An over or under dampened coil will cause instability and or mask the fact conducting metals such as gold as well as reduce detection depth.

When a metal object nears the loop it will store some of the energy from the reflected pulse and will increase the time it takes for the pulse to decay to zero. The change in the width of the reflected pulse is measured to signal the presents of a metal target.

In order to detect a metal object we need to concern ourselves with the portion of the reflected pulse where it decays to zero. The transmit coil is coupled the receiver through a resister and a diode clipping circuit. The diodes limit the amount of transmit coil voltage reaching the receiver to less than one volt so the transmit pulse and the reflected pulse. The receiver has a typical gain of 60 decibels. This means the area where the reflected pulse reaches zero is amplified 1,000 times.

Sampling Circuit
The amplified signal coming from the receiver is connected to a switching circuit which samples the reflected portion of the pulse as it reaches zero. The reflected pulse up to this point references in actuality a series of pulses at the transmit frequency. When a metal object nears the coil the transmit potion of the signal will remain unchanged while the reflected portion of the pulse will become wider. The metal object stores some of the electrical energy from the transmit pulse and increases the time it takes for the reflected pulse to reach zero. An increase in duration of a few millionths of a second is enough to allow the detection of a metal target. The reflected pulse is sampled with an electronic switch controlled by a series of pulses, which are synchronized with the transmitter.

The most sensitive sampling point on the reflected pulse is as near as possible to the point where it reaches zero. This is typically about 20 millionths of a second after the transmitter shuts off and the reflected pulse begins. Unfortunately, this is also the area where a PI can become unstable. For this reason most PI models sample the reflected pulse at a decay of 30 or 40 millionths of a second, well after it decays to zero.

Integrator
In order for an object to be detected the sample signals must be converted to a DC voltage. This task is performed by a circuit call integrator. It averages the sampled pulses over time to provide a reference voltage. This DC reference voltage increases when metal nears the coil, then decreases as the object moves away. The DC voltage is amplified and controls the audio output circuitry which increases in pitch and/or volume to signal the presents of metal.

The time constant of the integrator determines how quickly the detector will respond to a metal object. A long time constant (in the range of seconds) has the advantage of reducing noise and making the detector easier to tune. Long time constants require a very slow sweep of the coil because a target might be missed if it passes quickly by the search coil. Short time constants (in the range of tenths of a second) respond more quickly to targets. This allows a quicker sweep of the loop however, it also allow more noise and instability.

Discrimination
PI metal detectors are not capable of the same degree of discrimination as VLF detectors.

By increasing the time period between transmitter shut-off and the sampling point (pulse delay), certain metal items can be rejected. Aluminum foil will be the first to be rejected, followed by nickel, pull tabs and gold. Some coins can be rejected at very long sample delays, however, iron cannot be rejected.

There have been many attempts to design a PI than can reject iron however these attempts have had limited results. Iron is detectable at very long time delays however, silver and copper have similar characteristics. Such long time delays also have a negative affect on detection depth. Ground mineralization will cause some widening of the reflected pulse as well, changing the point at which a target responds or rejects. If the time delay is adjusted so that a gold ring doesn't respond in an air test, that same ring may respond in mineralized ground. Mineralized ground thus changes everything regarding the time delays and discrimination of PI detectors.

Ground Balance
Ground balancing, while very critical on VLF detectors, is not necessary with PI circuits. Average ground mineralization will not store any appreciable amount of energy from the search coil and will not usually produce a signal. Such ground will not mask the signal from a buried object. On the contrary, ground mineralization will add slightly to the duration of the reflected pulse increasing the depth of detection. The term "automatic ground balance" is often applied to PI instruments because it will normally not react to mineralization and there are no external adjustments for any specific ground conditions.

Heavy black sand is an exception. It will cause a VLF coil to overload, making detector penetration poor at best. A PI detector will work in black sand however, some false signals may result if the coil is held very close to the ground. Ground responses can be minimized by using a longer time delay between the shut-off and sample point (pulse decay). Advancing the time delay slightly will help to smooth out the noises caused by most mineralization.

Automatic vs. Manual Tuning
Most PI detectors are manually tuned. This means the operator has to adjust a control until a clicking or buzzing sound is heard in the headphones. If the search conditions change, such as when moving from black sand to neutral sand or from dry land to salt water, the tuning must be re-adjusted. Failure to do so can result in reduced detection depth and missed targets. Manual tuning is very difficult with short integration time constants, so most manually tuned models use long time constants and the search coil must be swept slowly.

This is not a problem when a PI is used for scuba diving because the coil cannot be swept quickly underwater. When used at the surf ling, where coil will be in and out of saltwater, a manually tuned detector can be frustrating to use. The tuner must be adjusted to continually maintain a threshold. Some operators elect to set is lightly below the threshold however, than can result in a reduction in depth as the ground conditions change.

Automatic tuning, or S.A.T. (Self Adjusting Threshold) offers a significant advantage when searching in and out of salt water of over mineralized ground. S.A.T. helps keep the detector operating at maximum sensitivity without requiring constant adjustments by the operator. It improves stability, reduces noise, and allows higher gain settings to be used. PI detectors do not emit strong, negative signals like a VLF. As such they do not "overshoot" on pockets of mineralization. With S.A.T. the coil must be kept in motion while detecting a target. Stopping over a target will cause the S.A.T. to tune it out or cease responding.

Audio Circuits
PI audio circuits generally fall into two categories: variable pitch and variable volume. Variable pitch or V.C.O. (Voltage Controlled Oscillator) audio has the advantage for faint targets because the change in pitch is easier to hear than a change in volume at lower audio levels. This is primarily true for manually tuned models. The "fire siren" sounds can become annoying and many have trouble hearing the higher tones. A variant of this is the mechanical vibrator device primarily used for deep water. It emits a slow clicking sound and vibration that increases to a buzz to signal a find. The mechanical device is easier to hear and feel over the sound of an underwater air supply.

Many people prefer a more conventional audio tone that increases in volume rather than pitch to signal find. This audio system works best with a PI detector that has a fast target response and automatic tuning (S.A.T.). Automatic tuning makes the PI sound and respond similar to a typical VLF detector.

PI Summary
Pulse Induction metal detectors are specialized instruments. They are generally not suitable for coin hunting urban areas because they do not have the ability to identify or reject ferrous (iron) trash. They can be used for relic hunting rural areas where iron trash is not present in large quantities, or is desire. They are intended for maximum depth under extreme search conditions such as salt-water beaches and highly mineralized ground. In such conditions PI type detectors produce superior results when compared to VLF models, particularly in the ability to ignore such extreme ground and penetrate it for maximum depth.

Narrawa wrote:All good mate, no need to explain to me the importance of having the new ML PI. I'll be getting one myself.

Just to cap off why i said depth to your question......from the outings iv had with the FG so far....depth at the end of the day makes all the difference. On more than one occasion it out performed the MXT on depth. And the MXT is certainly no slouch. But, in order to dig a target, you must be able to hear it first.

Yeah mate I get what you mean i think I'll still buy one after I buy the gpz.
Just have to wait and see how I am for cash after buying 2 of the suckers and expenses to start the detecting season
As you know a good VLF is very handy in some situations and the fors seems like it is up there at the top of the VLF shelf.

I currently use a gold bug and the CTX to for fill this task but the fors looks like it would do it better.

Got out to one old park today with the FG and F19 for a little park hunt.
This ground is not near any Goldfields and had a much lower ground reading of 55-70....in the areas i worked mainly, it never went over 65.
Iv been to this park many times over the years with VLFs iv had in the past, and is not one that is hit by locals very often, this can be seen by the amount of trash in the pic below.
Kicking off in the sand pit turned up nothing but foil for me, so i ventured off to the areas of interest where i did ok yrs before with the other VLFs.

This first spot of interest gave up many coins to me in one day due to it being under the limb of a very old and large tree. The tell tail signs on the limb tell a story of how many a child have used the tree for climbing, and whilst doing so, emptying their pockets into the mulch directly below.
Not being disappointed on arrival with the first two bob being found strait off the bat. Loud and clear on the FG with a reading of 68 when side stepping the other targets near by. After a quick cherry pick of the spot....and soon sharing it with a women operating an F19, my cherry picking came to a share factor and fight for territory. So i started the task of cleaning up and learning what other numbers were telling me along with putting more time into the audio and ID mask.
54...foil..loud and clear and at depths that caused the Lesche to become problematic due to its awkwardness for digging very hard ground....wrong tool for this spot...oh well. Most foil came in at around the 54-56 mark, and it became very easy to predict when under the coil. However i chose to dig most targets today for the purpose of learning how well you can predict what the digits are telling you. This became so very easy to do, and at times i decided not to dig certain numbers in the foil range, and is probably why i got no rings today in my haul.?
Ring pulls, did i mention i dug a few ring pulls.... While most came in round the 67-68 mark, many didn't, those are the ones that were not uniform, or laying flat in the ground, some with tails bent round through the ring= 70-72 and others bent out of shape had alternating numbers, but the tones were constant.
Upping the ID mask to 35 and gain of 65 i found the detector still allowed certain nails through to the keeper. Yet small wire was no problem at all. Upping the ID mask tends to make the audio much tighter as the iron still likes to be noted with a lead-in or out iron report, hard to describe but there are still subtle reports of iron mixed in, or on the tail end of the higher tone on none ferrous targets. Rusted bottle caps still report anywhere from 80-89 shape dependent and the majority reporting in on 82/83 if laying flat. On edge with the slightly higher ID mask set to 35, and no report of the dreaded things to report, they simply vanish.

The audio of the FG is hiding something not seen in other detectors in my opinion, what it is i find hard to put into words.... but there is something in the audio thats certainly worth more investigation....whether or not it can be put into words im not sure even if the light bulb comes on.?


The speed in which the FG reports both visually and through its audio, is very snappy, and the ability to pull targets next to one another is simply stunning for a mid freq detector using the std size coil. While i have the small DD to test more of the abilities of the FG with in iron infested locations, the std coil is proving adequate. A coil of the dimensions 11x5" would serve this detector even better in these locations for unmasking, and still covering some ground and maintaining reasonable depth. The same size coil in concentric configuration would also be a worthy accessory coil to have on hand for areas not so mineralized. Actually a 11" round concentric should also be added to that list for the folk who like the deeper digs. I Know the benefits of concentric coils, but unless you get the center of the coil over your target, its just not happening....i need a coil thats sensitive right to the very tip to work in the locations i want a good VLF to benefit me. The FG with its ample gain could be that very detector if it had the right coil mounted on it.
During todays hunt, the detector overloaded many times on our coins and ring pulls. Lifting the coil far above some targets was the only way to get audio report other than changing settings, which is time consuming and boring.

Testing against the F19 today over some targets was quite eye catching when you think about that model detector....19khz vs 15khz.....10x5 coil vs 11x7...gain flat out vs 65 on the FG, and yet in my eyes it out performed it and had no problems separating the same targets as the F19 did, or for that matter signaling with the audio finesse on some very small targets.


My reports on the FG were to be more goldfield based, but from my findings so far i cant see it being better than most others able to operate on our goldfields. Still more time is needed with it and the no gold show on my behalf is not causing me any stress. I know it has the potential to do this like most other models, and soon enough it will. Im not into staged pics or vids, anyone can do this or report findings that are not legit.



The dark coin in the middle was the best find...1917 British one penny. A few other penny's found also.
My partners finds consisted of current coins with the F19, and two bits of jewelry not pictured.

The hunt continues.

Returned to the same park for another look see with the FG today.
Cant quite pick what it is about this detectors audio when anmasking of targets in very close proximity...whatever it is, it does it well.

Got this one today among other items of little interest, a few current coins, an earring or two......ok ok so the second earring was still attached to me woman's head. ...still classed as a find.
Forgot our digging tools, so had to call into Bunnings on the way and opt for a couple of nasty substitutes. And as a result, i put some much needed stripes on this one.


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Can you see the date?...here, have a closer look and pay no attention to the GT stripes left by the digging tool that was way out of control...not my fault i tell ya. What do you expect for  $3..?.. it was out of alignment.... its not a precision instrument is all im trying to say....made in China?.....get off my back alright!!!  


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Besides, it was like 49-no wait... it was 87deg a sh!t you not. Well it was pretty hot anyway, and that can make a big difference to how one actively go's about retrieving his/her finds.

Seriously, this machine is causing dust to gather on my Whites V3I which is causing a little anxiety.

Hoping the RACER has the same audio traits as the FG.

Central West Prospecting Supplies Mudgee is stocking the Nokta/Makro range of products, including the new RACER...which i had my hands on today.
Impressive lightweight little VLF detector indeed.

I'll have my hands on one permanently latter this week.

I'll keep regular posts on how its going as i put it through its paces in a range of locations as iv been doing with the FG model...which i'll now hand down to my other half who had her hands on it, and lost interest in her own detectors since doing so.

Cant wait for a day off to give it a try.