Steve Herschbach

Figure 2 shows a comparison between the ZVT VRM soil signal and the nearest equivalent PI soil VRM signal; both transmitted magnetic signals being bi‐polar, with the same fundamental frequency and same rapid change of magnetic field period. It should be noted that the PI receive period is half that of the ZVT period, because the PI system shown in figure 2 transmits for half the time and receives for the other half of the time, unlike ZVT that transmits and receives simultaneously just about all of the time. The important difference in the VRM signals is that the PI signal decays away substantially faster than the ZVT system. This indicates that the receive signal for PI is less sensitive to longer Time Constant (TC) components compared to shorter TC targets than ZVT, and this is one of the main reasons why ZVT technology is better at detecting large nuggets compared to PI; another main reason being from the double length receive period in ZVT compared to PI for the same fundamental frequency.

I find it very hard to choose between the F19, Racer, and FORS CoRe. They are very close in performance. For those liking a long reach or the use of large coils, the FORS is better balanced. Racer is slightly nose heavy and F19 more so, making them better for short rods and small coils.

Interesting Australian opinion on F19 vs Racer in really bad ground https://www.prospectingaustralia.com.au/forum/viewtopic.php?id=11147

I am still holding out for the Gold Racer but do not know how long it will be. I will be using Racer and FORS and F75 until it appears, by which time I am also hoping the black and gold F19 will finally appear. I guess I will finally sort it all out by winter. I will probably have another detector clearance sale before the end of the year.

More information on the new Makro Racer

The target id range for the Teknetics T2, Gold Bug Pro, F19, FORS Gold & CoRe and Gold Racer are nearly the same, with non-ferrous ranging from 40 to 99. High frequency detectors have more VDI spread on the low conductive end and compress more on the high end. Low frequency detectors just the opposite. The low conductors tend to be closer together, and more target resolution on the high end.

http://www.detectorprospector.com/forum/topic/532-nokta-fors-and-makro-racer-vdi-chart/

http://www.detectorprospector.com/forum/topic/526-fors-gold-f75-v3i-tone-and-vdi-tidbits/

"Native" target VDI ranges can be "normalized". You are probably familiar with the fact that the DEUS VDI numbers change depending on the frequency you select. 18 kHz compresses high end numbers as described and in fact appears worse than some with most coins lumped in the 90s range http://metaldetectingforum.com/showpost.php?p=1428436&postcount=7. I believe the latest version of the software offers the ability to normalize VDI numbers across frequency choices?

The White's V3i lets you pick any one of three frequencies. You can run each frequency with its native VDI range, or chose to normalize the VDI numbers. Normalize means make them all the same, regardless of frequency. Usually they will be normalized to a middle frequency, in the case of the V3i it is 7.5 kHz.

So, if you really care about whether it is a penny or a dime or a quarter or a half dollar, running a detector in a low frequency is better, especially with native VDI numbers, as you get more target spread (less lumping) in the coin range. Conversely, for jewelry detecting running high frequency native VDI numbers gets you more spread in the gold/lead/aluminum range.

Bottom line, the Gold Bug Pro, F19, FORS Gold & CoRe, and Racer all lump copper pennies, dimes, and quarters into the same fairly tight range. Wouldn't you just dig them all anyway?

You want adjustable VDI spreads nothing beats a White's V3i.

I would not expect General to outperform High Yield on air tests myself. That is sort of like air testing a high frequency Gold Bug 2 against a lower frequency detector. The Gold Bug 2 wins the air test and loses the in ground test. It is the performance in ground relative to the ground mineralization that makes all the difference in the world.

Reading the Aussie forums again?

High Yield is the loose equivalent of a short pulse delay timing. Very hot. General would be a longer delay type setting, less hot on tiny stuff but allows for clearer signals on medium gold. Extra Deep would be the equivalent of a long pulse delay setting only for very large targets but gives up a lot on the smaller stuff. Not a good mode for general gold prospecting, but may be good for dialing down the sensitivity for small surface trash and so useful in really trashy locations or for relic hunting. Or for looking for that really big deep nugget people are convinced they are going to find.

50 grams may as well say a couple ounces. If you are hunting 2 oz plus nuggets this is the mode to go with in theory. I doubt Minelab made it up as a marketing ploy. If they say it will punch deeper than the other modes, it probably will. But only on massive targets.

Extra Deep may or may not give up depth on those big bullets. Even a bit of lost depth may be ok if tiny surface stuff can be ignored. Definitely a setting I will be experimenting with more.

Hi Bob,

Not off topic at all, as it says in the forum header "A forum dedicated to prospecting for gold and other precious items using metal detectors, suction dredges, sluice boxes, gold pans, and more. Metal detecting for coins, jewelry, relics, meteorites, etc."

I am vitally interested in your links because there is a huge overlap in what relic hunters in very mineralized ground are doing and what prospectors are doing. It is all about max depth in bad ground, and relic hunters back east have discovered what prospectors have known for a long time - nothing can match a good pulse induction for depth. Until now with the new GPZ.

I knew the GPZ had the power, but what I have been wondering about is the issue with it being so hot on small stuff. This is generally good for prospectors, but I thought maybe it would be a real problem for the relic hunters and tiny surface trash. I wonder if the Extra Deep mode might ignore that small surface trash while still punching deep on those bullets, etc.

It looks like the GPZ once again proves it packs the punch. If people can deal with the trash issue it may be the next big thing in relic hunting, especially at DIV. The bottom line is that wherever good finds exist somebody is eventually going to put a GPZ on it, even if it means digging all the junk. Thanks for posting as I will be following it all with interest.

Going after trashy for those with the fortitude to slowly get it out of the way is a good strategy, provided of course that there is a decent chance gold is lurking. People with PI detectors tend to avoid trashy sites, yet mining camps were often built on the richest ground. You are in the right area for sure, just have to be persistent and keep at it. It took me years to find my first gold nugget with a detector, but once the first one happens, it is like a dam breaking loose. Many, many people report a similar experience. That first one is the hardest for all but the very few. Good luck!!

a few more tips....

Steve's Guide to Metal Detecting For Gold Nuggets

There has been another big nugget find in Australia - by an 81 year old grandmother! 18.85 ounces.

http://www.9news.com.au/national/2015/03/25/07/16/victorian-grandma-finds-gold-nugget

There was the 87 oz find recently http://www.detectorprospector.com/forum/topic/711-87-ounce-gold-nugget-found-in-victoria-australia/

And the 6 pound nugget from California http://www.detectorprospector.com/forum/topic/367-monster-multi-pounder-nugget-found-in-northern-california/

Every one of these large nuggets could have been found with just about any decent metal detector made. They were all quite shallow.

The largest nugget ever found with a metal detector, the Hand of Faith, was found decades ago with a VLF. In fact, most all of the largest nuggets found with metal detectors were found decades ago with VLF detectors.

This reveals a basic reality. Yes, there are large nuggets at depth, but for various reasons in desert terrain the largest gold is often found very shallow. In the 1800s when they found new gold locations nuggets were literally just sitting around waiting to be picked up.

So while it is true new technology is producing more gold at depth, when it comes to chasing those really big monster nuggets, a surprising number being found even today are simply ones that have been missed by everyone up until now. To find one, you do not need a super detector, you need to put your coil over ground that has not yet ever seen a coil. Those expecting lots of large nuggets to appear from ground pounded by others for decades just because a new detector gets a few more inches are likely to be disappointed. It is going to happen, just not near as often as people expect.

Nugget #4
 

Also from Doc - Nugget #2

And Nugget #3

A likely nugget find is made in Arizona and settings tested on it before digging. From our good friend Doc.

Maybe Rob can get Nokta now? I encouraged him to get Makro because Kellyco had Nokta locked up and also because of the upcoming Makro Gold Racer.

Hello Mathew,

Welcome to the forum!

Sounds like as far as the detector goes you have it figured out. It is simply a metal detector and you have it detecting metal. Bullets and lead are the best indicator of your detecting skill. The smaller the bullets you find and the deeper they are, then the better you are doing. Lead and gold read approximately the same.

Now you just need to put the detector coil over some gold. Buying a detector is easy, getting it to work is actually pretty easy. Getting the coil over detectable gold - not so easy. Like buying real estate it is all about location, and that knowledge is gained through research. The easiest solution for beginners is to go where gold has already been found. Most any decent gold location will usually give up at least one more gold nugget if hunted patiently. In order to do more than find just a few nuggets you have to get off the beaten path and explore hard to reach locations. This involves more research and a willingness to take risks in the form of time spent detecting places where good has not been found before by many others. Learning as much about gold geology as possible, including reading geologic maps, is very key to success.

Bottom line? Metal detecting is easy. Prospecting is not. Most people can become reasonably good with a detector. Becoming a good prospector is a totally different thing in that what you are learning is where and how to place yourself over shallow detectable gold. In the U.S. I usually recommend joining a club to meet others whole may be able to act as guides and mentors. I am not sure if the equivalent resource exists in Australia?

Gold Fossicking Australia http://www.gold-net.com.au/fossicking1.html

Gold Prospecting U.S. http://geology.com/articles/gold-prospecting-tools/

Patch Hunting http://www.minelab.com/emea/treasure-talk/so-you-want-to-find-a-patch

Very interesting. More choices in suppliers is always better!

Good job on the gold and great photos - thanks! Bummer about the pick though. Been there, done that.

The WM 12 is line of sight. Mine perched on my left shoulder cuts out a smidgeon now and then. But nothing like you describe. Do a reset and re-pair it with the GPZ. Should solve the problem hopefully.

The postage thing works different ways different places apparently. When my CTX 3030 had to go back to Minelab U.S.A. for a GPS fix they paid postage both ways. Best thing is if you buy from a dealer - just take it back to the dealer. Not sure what was up with the situation as reported in Oz but if it were me I would be raising a fuss.

It can be worse and is not as out of the ordinary as you may think. I was the largest Ski-Doo snowmobile dealer in North America, based in Alaska. If you lived in middle of nowhere Alaska it might cost $1000 just to have the snowmobile air freighted out to you. Now after 100 hours to motor blows up under warranty. The warranty states must return item to nearest warranty center at your expense. Why? Ski-Doo did not make you live in the middle of nowhere. Your choice, along with the consequences. So you have to pay to ship the machine airfreight back to town to get your warranty work done, then pay again to get it shipped back out. Huge freight bills. And this was not just Ski-Doo, it was most anything and just life in Alaska.

I conjecture the warranty for Minelab in Oz says return to warranty center for repairs. If that means a short drive or shipping across the continent it could cost. Not excusing it or anything mind you, but do read warranties for big ticket items before making purchases to prevent unpleasant surprises.

I am going to go grab my warranty from my GPZ right now, copy it, and post it on a new thread.

http://golddetecting.4umer.net/t21243-3-gpz-s-in-the-field-for-a-week-review

This is a well written and informative report. Unfortunately, I am not surprised to hear about a bad coil in one respect due to the complexity of the coil. On the other hand, how in the world does a $10,000 detector get out the factory door with a bad coil? I understand a company cranking $500 detectors out the door can't check every one. But for $10K that would seem to be something the purchaser is paying for. Hopefully just early days issues with quality control that will get sorted out.

I have noted elsewhere that the GPZ 14 coil gives really complex targets response up close when the target is near the windings. Double blips, reversing tones, etc. The deeper responses are more even and "normal". Interesting that these blokes have used that as a sort of shallow target discrimination feature, going only for deeper mellow targets and ignoring the complex surface signals in trashy areas. Would work very well in birdshot, for instance. You would miss a very shallow nugget also but the method is a sound one for trashy locations.

I have not noticed it specifically with the GPZ but I have observed it with other detectors. The reality is that ferrous targets and ground iron mineralization overlap to a certain degree and ground balancing not only removes ground effects but some ferrous targets. In thick ferrous trash tracking systems can "track into the iron" with ill effects and so manual ground balance is preferred in those situations. What we really want is a ground balance system that would balance out ferrous trash along with the ground and still show us the non-ferrous items, but unfortunately we are not there yet. Ground minerals are magnetic but generally have little or no conductivity worth noting except for alkali or salt flat conditions. Ferrous metals on the other hand are not only magnetic but highly conductive which is where we get all the problems with steel items in particular. Ferrous metal that has almost completely rusted away is slowly turning into the original ferrous material from whence it came and so is more likely to be ground balanced out.

Meteorites grade from pure stone to pure metal and everywhere in between. When you think about it a meteorite is just a hot rock, so it makes sense that a good system for eliminating hot rocks would also tend to have the side effect of eliminating or reducing the signal from some meteorites. This would tend to happen more with those that have the least metal in them and are mostly stony in composition.

Like everything detecting it is all sort of relative. A meteorite in low mineral ground is going to stand out loud and clear because it differs so much from the ground, the very definition of a hot rock. The same meteorite in highly iron mineralized ground may be passed right up by the detector for being too close to the ground itself and therefore the current ground balance setting.

Best is what works.

A big issue in metal detector land is stability versus depth and sensitivity. Usually, the hotter you make a detector the more noise you get in the form of ground noise and potentially electrical interference.

In VLF detectors this has been a big issue with the Fisher F75. It is an extremely hot, high gain detector, but had always had issues with being noisy. So noisy in some urban areas as to be unusable. Recent upgrades to the machine focused on alleviating this issue, only to create more problems with lost depth and sensitivity. It has pretty much been sorted out now, but it highlights how hard it is to create extremely powerful metal detectors that can run quietly, only detecting what we want.

Early Minelab PI detectors all had a warble that kind of drove me nuts. I would hear it in my head hours after turning the machine off! Newer models improved the threshold until the GPX got it perfect.

Now, in an attempt to get hotter, we got the SDC 2300 along with a ratty threshold some people find unpleasant. You can tame the noise but at the same time you lose an edge in sensitivity. Maybe. If the noise is distracting you so much you miss a signal, that is no good either. There is a lot to be said for smooth, stable theshold sounds. It allows faint signals to stand out as opposed to hearing a sharper faint signal in the midst of a barrage of noise.

The GPZ is not as bad as the SDC and can be made to run with a smooth threshold but the operator still faces what I think is a personal choice issue. Some people can tolerate more noise on a continuous basis and still pick out actual targets when they occur. Others lose those targets in the midst of the noise and are better served making the threshold as smooth as possible to make the targets more obvious.

I don't think ultimately anyone can say one method is better than the other. In theory suppressing the noise may suppress some edge of detection targets. But if the noise makes the actual act of metal detecting oppressive for the operator that is going to be a losing situation. Doing this all day for days on end, I need the experience to be pleasant. I am not out there to torture myself to the point of being relieved to quit detecting. It is tiring enough work as it is.

Long winded response but I like what you are doing jasong. I think there is room for both methodologies. I tend to go for smooth and relatively quiet when spending long hours patch hunting. I want to go for a nice wander and enjoy life without listening to noise all day. But when I am on that patch, getting real down and dirty, that is the time to pull out the stops and run the machine hotter and noisier if need be, especially on pounded patches.

One thing for sure. A tame GPZ is still more powerful than almost any detector on the planet regardless of settings!

Still learning myself. I figure by the end of summer I will have it sorted out, but until then all the notes we can all contribute about the GPZ and our experiences will help us all. Thanks!

Thanks Gold Hound, any suggestions appreciated. The problem is there is always more to talk about with the GPX. Just trying to explain that the Special Switch is really just selecting something else set somewhere else gets confusing. The big fail on the GPX was in not allowing the custom modes to be fully custom. You can only save some settings and not others so most people ignored them. If I could have had just one simple change though it would be to swap the threshold setting from the knob into the menu and put the RX Gain on the knob. I almost never messed with my threshold setting but was always wanting to tweak the gain.

I once talked to the engineers and suggested they develop a system of "automatic timings". The GPX knows enough to sense and adjust the ground balance. So it knows when the ground is bad. Why not just suggest to the operator based on what it is seeing what timing to use, or even have that adjust automatically on the fly? He thought it a great concept, but I think even then the GPZ was already on the drawing board so it went nowhere.

This is as simple a basic guide as I can imagine, and simple is often best. You can get a GPX real screwed up fiddling with the settings! So the most important tip of all is The Factory Reset.

OK, you have a fresh start. The GPX will save your changes going forward when you turn the detector off. If you get worried or confused, just do the Factory Reset again.

I think there are three very basic Soil settings (or Timings as Minelab calls them) on the GPX 5000 for beginners, all which use the stock 11" mono coil. The GPX series was designed with mono coils in mind so just start there. The three Timings are Normal, Fine Gold, and Sensitive Extra.

Normal is the "go to" mode for the beginner. Set all the switches on the front control panel as follows:

A. Turn the detector on by pressing and releasing the power switch on the rear control panel, the same one used to do the Factory Reset above. B. Raise the coil off the ground and press the Auto Tune button to reduce electrical interference. The tuning process takes approximately 60 seconds. Do not move the coil or pass metal objects near the coil until you hear 3 beeps. C. Turn the Threshold control clockwise until a hum is audible through the headphones. D. Press and hold the green Quick-Track button on the end of the foam covered handle. While holding the button depressed, raise and lower the coil, between 1" and 4" (25mm and 100mm) from the ground. You may or may not hear variations in the Threshold sound while doing this. Any variations in the Threshold will smooth out within 3–5 seconds. Release the Quick-Track button. You have just ground balanced the detector. E. Again adjust the Threshold to a very faint but still audible level. It should be smooth with only minor fluctuations.

You are now ready to go find gold! There really is only one other key adjustment the beginner needs to know at this time. On the rear control panel turn the Function Select knob until the RX Gain setting is highlighted.

The default setting is 11. If the detector is operated a short while and everything seems very stable, try adjusting this setting up a couple notches. If you change the RX Gain, it is a good idea to do the ground balance procedure above again after making the adjustment. Turning the Setting knob adjusts the RX Gain up and down. This is the basic sensitivity setting for the detector. Higher settings give you more depth, but also make the detector more susceptible to electrical interference and ground noise. The goal is to find a higher setting that does not make the detector threshold too unstable. You want a smooth threshold or as near to it as possible. On the other hand, if the default setting of 11 seems too unstable, reducing the RX Gain will help. Settings of 14 or 16 are not unusual, nor are settings as low as 8 or 9.

The real secret to nugget detecting is coil control. Sweep over the ground while either scraping the ground with the coil or keeping it 1mm off the ground. I see people obsess over getting the best detector setting, then give it all up and more waving the coil an inch or two or three over the ground! Careful methodical hunting and attention to faint signals is the best way to learn.

There are two alternate Timings I want the beginner to know. Fine Gold and Sensitive Extra. Think of Normal as just that - Normal Mineralization. Fine Gold is a bad name for a setting that is better thought of as Difficult Mineralization. Sensitive Extra should be thought of as Low Mineralization. If the GPX does not want to run smoothly in the Normal Timing and is having problems with ground noise or hot rocks, even if you lower the RX gain a bit, flip the Soil/Timings switch to Special.

The Special Timings are selected via the LCD menu but the default is factory set for the Fine Gold timing. Simply flipping the Soil/Timing switch to Special puts you in Fine Gold. If you have been messing with the RX Gain while in Normal you may want to go back to 11 or 12 at this point, and again do the ground balance procedure as described above. Fine Gold, despite the name, was designed specifically for bad ground and eliminates all but the worst hot rocks. It is the preferred setting for bad ground. It runs so well people get in the habit of using it all the time. Do not do this, it does miss gold that can be found in the other two Timings discussed here. The key always with the GPX however is to seek quiet, stable operation, and Fine Gold does this very well. Again, experiment to find the highest RX Gain setting that you can run while maintaining stable operation.

If in the United States in particular you may run into areas where the mineralization is low. You will know because you will be able to run in Normal with the Gain set very high, like 17 or above. If so, give Sensitive Extra a try. This is a very powerful and sensitive setting, and actually is the hottest setting for small gold nuggets, not Fine Gold as the name suggests. To try Sensitive Extra, again you need to switch from Normal to Special with the Soil/Timings switch. But now you need to use the LCD menu Function Select to find the SPECIAL settings. This determines what happens when you set the Special switch. Adjust the setting from the factory preset (FP) of FINE GOLD to SENS EXTRA.

The Special switch now means Sensitive Extra. You can flip to Normal, and if you go back to Special you will be in Sensitive Extra. This will happen until you use the LCD menu to change the SPECIAL setting back to FINE GOLD or a different alternate timing. You are programming the Special switch setting to be whatever you want. The best thing at some point is to have Normal set up with either Fine Gold or Sensitive Extra as a preferred alternative, depending on the ground types you encounter most. Remember that if you ever do a Factory Reset that Fine Gold will become the default setting for the Special switch.

Now that you are in Sensitive Extra, you probably need to go back to the RX Gain setting default of 11 again to start, and ground balance again. Seeing the pattern here, change timings or gain, you should ground balance again. Here is more detail on the ground balance procedure and how to check it periodically. Maintaining proper ground balance is critical.

If going to Sensitive Extra starts causing problems with hot rocks or ground noise, just go back to Normal.

OK, to sum up. Normal for Normal ground conditions. Normal is the key and your reference point. If Normal is having problems, then use Fine Gold for bad ground and hot rocks. If Normal is working almost too well, try Sensitive Extra for mild ground/minimal hot rocks. In each Timing find the highest RX Gain that will allow stable operation. Check your ground balance often and do again whenever in doubt. Go slow and carefully, and when learning investigate all targets. If you are digging ground signals or hot rocks, use lower gain levels or change Timings.

That should cover most beginners and even a lot of regular users just fine. If you hunt the same areas regularly you will figure out what works there and rarely need to change settings. The GPX is actually pretty forgiving compared to a hot VLF detector. This is of course only my suggestions, not set in stone, and maybe not as clear as I hope it is. If it is not clear enough please tell me or offer suggestions, but my goal is to make it simpler, not more complicated, if that is at all possible.

For additional details and information see the GPX 5000 Owners Guide and the detailed timings charts on this website.

OK, here we go. I have activated the forums Downloads area. Look at the menu at the top of the forum, Chose Downloads

Chose the CTX Programs category on left

Click in Upload File button in upper right

You can now upload the file from your computer. The file name is just the name or title you want displayed. You can give a more detailed description. I have uploaded a file already as an example and to test it works. Note:only forum members in good standing can upload and download files. Also, files are held until I scan them for possible virus infections, at which time I will approve them and they will be available for download. This adds a delay and is a bit overkill given the upload limitations built in but adds an extra layer of safety for forum members.

Assuming this works well I can add any category of downloads the forum membership wants to have available.

I never met Mark but have met many like him. I am sure he is a great guy. Most super enthusiastic detectorists I know are always more than happy to help people out detecting. I love sharing what I know about detecting and helping get new people started at it. The best gig I ever had was running my operation at Moore Creek and seeing people every single week who never found a gold nugget in their life find the first one. We really made some lifetime experiences happen for people, great stuff.

Sounds like you have that same great attitude - you are guaranteed to do well!

Whole different subject but I do love my beach detecting - new thread soon.

I know the delay was not to be desired, but I like what Minelab did. Usually you would expect maybe being sent a new battery or charger or who knows and maybe that would or would not solve the problem. How many times have most of us had a problem with something and just wished we could get a whole new item, but were told no? Complete brand new unit from the ground up - problem solved!

On 3/24/2015 at 7:53 AM, Rege-PA said:

Great info, thanks for sharing! I now see why you are successful in chasing the weight, you squeeze every advantage out of your machine that it is capable of producing by thoroughly learning and experimenting with the settings. Most of us never reach this level of expertise with our detectors, the majority of us are "Turn and Go" junkies who never really realise what we are missing.

Many of us are in the same situation with the GPX 5000 and now with the introduction of the ZED are thirsting for some miracle settings that will give us some more depth and sensitivity, pray tell you have some?

There never will be miracle settings for the GPZ or most any other detector for that matter. You have to learn what the controls do, and the best way to do that is to use the machine. Each setting must be custom adjusted for each particular combination of ground type and gold. Anyone who uses a magic setting is a "Turn On and Go" junkie as you have described.

Even Gold Hounds suggestions are just that - suggestions that work best for his conditions.

Let's say you have a manual transmission car. What is the "magic setting" combination of gear setting and throttle setting that is best? Would that be third gear, half throttle, or fourth gear, one third throttle? It just depends on whether you are on a hill or not, whether you are passing someone or not. The gear shift and throttle exist with the sole intent of being adjusted as needed. So it is with the controls on your detector.

Some settings will never be more than educated guesses. On the GPZ I might use High Yield or General based on my best guess of the depth of the ground and the size of the gold I am after. Neither is right or wrong, it is just a judgement call based on experience and knowledge of the ground.

Some of us work solely in certain areas and so there really is a best setting for our situation. Somebody else somewhere else can settle on an entirely different "best setting". What works best for me in low mineral ground is not going to work best for somebody in extreme ground in Australia. Other people get around a lot, and so must be better prepared to adjust the machine for whatever conditions they encounter.

The vast majority of people I have encountered do not use their detectors enough to ever really learn what the controls do or how to properly adjust them. Reading has limitations. Read all you want about playing a guitar and you will get no closer to being able to play a guitar. Detectors are like that. You have to use them and use them constantly to stay good with them.