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Metal detecting

Mickster

Well-Known Member
Most Helpful Member
Anyone else here have a metal detector?

I have one of these on it's way to me and it should arrive early next week:

There seems to be pretty good reviews of this model, as an above-entry-level device, so I thought it was worth a punt just in case it's something that we may be become bored of 6 months down the line, and can recoup some cash from passing it on to someone else. If the bug bites, we could get something better.
The price of this item works and it has the benefit of being something of a distraction...
My step-daughter is off to college in Canada, just under a month from now, and there is going to be a huge hole in my wife's daily responsibilities as a mother, going from practically 100%, to near 0%.
She's up for going out treasure-hunting, recognizing the very slim chances of finding something of value, but I think the focus required to interpret/pinpoint a target may help her take her mind off this sudden transition.

I'm happy to let her operate the detector, and dig ring-pull targets myself all day if need be, but what I'm after are good locations that may find something better on a beach.

For those that may have and use a metal detector, where would be your first choice of searching a beach, after having used one for some time?

Would you start where the towels might get laid out, just up but still close to the shore line?
Would you start way up the beach from the water?
Would you start in the surf/shallows? (I believe this model has a waterproof coil)
Would you start on the trails leading to/from the beach?

Thanks for any input that can be provided.
I recognize that there are plenty of sites/forums out there on the interwebs, which cater solely to metal detecting, but I would trust members opinions from here first, since nobody here is likely to be trying to sell me something, or directing me to a seller in order to earn some commission.
 
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HarveyH55

New Member
I metal detected for a few years, but haven't been out in a while, got involved in a few other things. I live in Florida, so only have a few months of ideal outdoor weather to play with, then it's hot and sweaty, or rains a lot. It's fun, but can be a lot of work and disappointment too. There are rules and regulations for places you can detect, some places are completely off limits, and some serious consequences if caught. The metal detecting forums aren't great for getting straight answers, pretty sure many of those people type more than hunt, mind wanders a lot while out swing that coil back and forth. I stopped using those forums after a while, too much bad information being shared, some was more of a joke, but some actually believe, nobody corrects them. Historical sites, like old parks, are usually off limits, but some of the jokers would suggest to go a night. Lot of other advice, figured was mostly fantasy, and probably get some people in trouble. Of course, with any hobby, the newest, and most expensive, is always the best, and everything is junk.

The reality, is there is tons of trash out there, most of which can sound, and register like something good. You never really know, until you dig it up. Sometimes even a piece of rust junk can look pretty cool. Who knows, it might sound like a rusty can, the screen says iron, but it's a can full of coins. Basically, if you are only interest in silver and gold, and set up you detector to reject everything else, you'll mostly just be walking around, when it does beep, it can still be trash. You get better at listen to the tones over time, there are some subtle differences, if you get tired of digging trash, but can still some good stuff. Learn that in my own yard, a few times. My house was built in 1946, so figured there should be some silver, only one dime though. Did find quite a few more modern coins though, real close.

My thing was to hunt the little strip of grass, between the street and the sidewalk, grass median too. I live in a small town, don't get a lot of attitude from people. That little strip is a mystery to most, as to who actually owns it, and what can be done there. Never had a problem or foul word, but I didn't make a mess, skip over sections people took real good care of, and didn't stay too long in one spot. Usually not a lot of trash, coins, some interesting items, lot of keys. I never really found a lot of silver and gold though, one wedding band, a few sterling silver pieces. Nice St. Christopher medal. Several pieces of chain, never bothered to get tested, one is probably gold, yellow all through, not discolored (green). It's adventure, sometimes you get rewarded, but mostly don't expect too much, more fun that way. Parks are usually pretty trash, not very productive for the work, and you need to be extra careful to fill you hole back nice. Tough to do in our sand, we call soil. The few times I went to parks, I asked the attendant first, to make sure it was okay, usually, don't make a mess, stay off the sports field. Only had a few people that didn't seem too thrilled with what I was doing, but they didn't push. It's a small town, people have their opinions, be tend to respect others for theirs, long as you aren't doing any harm. You basically need to get out and try different places, see what works best for you. Be respectful of others, even though it's public property, somebody is responsible for taking care of it. Best to ask first, usually showing that little bit of respect, will get you a positive result., if possible. Some places are just off limits though, you should respect that too. Plenty of places to go, no need to get sneaky.

You best bet, is where people gather most. Some places, like parks, probably the beach, attracted the trashy kinds of people, which makes for more work. Most people try not to drop their valuables. Another thing about the beach, they have machines that they drive around, and sift through the sand, to collect trash, and everything else. They don't go very deep though. Sometimes big storms drag a lot of sand off the beach, and you get a shot at some old stuff. Sometimes the storms bring in more sand... It's a lot of luck and persistence, appreciate what you find.

Anyway, suggest you spend some time in your own yard at first, practice and play a little with your new toy. You can do what you want there. Need to learn to dig clean holes, that you can put back close to how it was, grass on top. Filling your holes in, even at the beach, is an important skill, usually what others might complain about most. You'll want to take the trash with you as well, you dug, it's yours to dispose of proper, besides, you might want to go through there again sometime (you never get it all, some places replenish), pointless to keep hitting the same piece of trash each time. Really, no way for anyone to know your comfort levels, something you have to find for yourself. You don't really need a fancy, expensive machine, just learn the one you have, takes time to learn to listen to it. Garrett makes good detectors, big company, all they do. I never owned one of theirs though, went with another brand. I never really trusted the computerized stuff, if you never dig the hole, you never know what you passed up. Fine, if you are looking for something specific, willing to walk around and wait for the machine to find a sure thing for you. I wanted gold an silver, but plain coins are fine too, not to mention unusual items. Chains and jewelry can ring up as anything. The deeper the item, the less reliable the computer ID. Its a very weak return signal, gets weaker with depth. I prefer to go with the sounds, lot of variations, but you can learn over time.
 

Mickster

Well-Known Member
Most Helpful Member
Hi Harvey,
thanks for your input. I will be practicing in the yard first, before going out and about, and checking where is allowed prior to that.

Regards.
 

HarveyH55

New Member
Wrote a long piece in the 'conversation' thing, figured it best to put it here as well, might be of interest to others as well...

Forgot to mention a few things about metal detecting, well actually there are a lot of things, most you'll figure out on your own. Most all coils are epoxy potted, mostly to keep the winds in place, so they don't get moved around, deformed when you bump it around. The waterproofing is just a bonus. No telling how water resistant the rest of your electronics might be. The coil shaft is hollow, should have a plug in there though, so water won't run down the pipe into the control box, when you lay it down to dig. Salt water is deadly to electronics. You can detect the surf just fine, just be careful around water. Check and see if the coil shaft is plugged, if not, do it yourself. Garrett is one of the original brands, and usually pretty good about all those little details, that ruin their machines.

Plastic coil covers are a good idea, if not already installed, they are relatively cheap. Some people don't like them, but epoxy isn't that durable, it's mostly used as a filler material, and intended to be filled, sanded, formed. You'll swing that coil a lot, and strike a few things, rub the ground. Coils are expensive, not to mention it does take much to change characteristics, meaning it'll still function, just not as expected, or intermittently. Might not notice the damage for weeks or months.

You want to swing your coil kind of slow, evenly, consistent height. Not sure how to describe 'slow', but suppose it's different for each machine, and each person. You'll get the idea, when you get out in your yard, Just throw a test target down, and keep the coil a little higher, maybe 3-4 inches. Surface targets overload the machine, great out in the wild, no digging required, but testing, it doesn't help much. Basically, you need to find what works best for you and your machine, the area you are hunting, how deep you want to dig. A lot of people can tell you how they do it, which may or may not work for you. If you swing too fast, you'll just have to go back over the spot, if you heard a tone, to see if there is really something there, and it sounds like something you want to dig up. My own yard, I'll dig till I reach China (not really), because I can take a break, leave the hole open a while, it's my mess. Off my property, I seldom go much more than 6 inches. That's a comfortable depth, easy quick, and fills back easy and clean. Deeper you go, the more time and work you put into recovering the target, and filling the hole. The depth and target ID readings get less reliable, further down from the coil as well. Never trust them much anyway, just an estimate, guess really. You can guess from the tones as well.

Headphones.... I use Bluetooth earbuds, and a relatively cheap, rechargeable transmitter that plugs into the jack. Headphone cords are a hassle to me, going wireless was one of the first things I fixed. There is a slight lag, but you learn to compensate, not really enough to throw you off at all. When you hear a target, your going to go back over it a few times, to pinpoint where to dig. You'll go a lot slower, different angles. The lag is basically a non-issue for metal detecting, only a little annoying when watching TV. Headphones, earbuds, or anything you choose, are better than the speaker, the cut the other noises around you, and you can better here the subtle differences in the tones. It's not just a frequency, but they pack a lot of other information into them as well, least my machine. How long you hear the tone, duration, tells you about how big the target might be. How loud or soft, tells you about depth. More conductive metals, like silver and gold, give a sharper, solid tone. Trash, things with rough edges, aren't as clear and clean. Jewelry has always sounded like a trash signal, even the target ID on screen suggested junk.

Anyway, it's best to hunt your own yard for a while, get comfortable, find what works best for you, see how long you want to swing, before taking a break. It's just a short walk, to get out of the heat. Oh, might consider bring a plastic bag, large enough to cover your control box, a rain jacket of sorts, if you suspect rain. Comes up kind of quick sometimes down here. The electronics might be splash resistant, but won't like a soaking.

Well this got loner than intended, sorry about that. There is still a whole lot more stuff, like tools and equipment you'll need for recovery...
 

Nigel Goodwin

Super Moderator
Most Helpful Member
The other year I was out walking, and was heading up towards Crich Stand (http://www.crich-memorial.org.uk/), and in the next field as you walked up the track to it there were loads of people with metal detectors. So been nosy, I went across and asked what they were doing - they were a local club, and had permission from the farmer to investigate the field.

As I watched them for a while, they all lined up at the bottom edge of the field side by side, and worked they way up the hill covering the entire field in a single pass. I don't know if they found anything or not, as I continued up to the Stand (and went up it - first time for years), and then carried on round past it round the edge of the quarry near by.
 

Mickster

Well-Known Member
Most Helpful Member
Thanks again Harvey,
I guess it’s mainly like anything else. You have to put the practice in, but you can’t beat getting good tips/advice.
 

HarveyH55

New Member
I don't mind sharing my experience, hope it helps. The metal detecting forums can give a lot more tips and tricks, but there is also a lot of misinformation, bad advice given. You don't need a ton of expensive gear, seems obvious, since you have to carry it all with you. I travel light, just the essentials. Expensive, isn't always better, or anymore useful. There are popularity clubs by price, mostly I think they want everyone to make the same purchases, to justify their own. I just did it for fun, no expectations of getting rich, so all the faster recovery stuff didn't make any difference to me, and I saved a lot of money and disappointment. You can get a handheld pinpointed, which is sometimes helpful, after you dug your hole, and can't seem to find the target. But I learned to pinpoint with my detector pretty good, shoved a small marker over the center, dug a circle around it. My targets usually popped right out, the soil here, is really just sand, doesn't hold together well, without roots. The handheld is good for letting you know if its still in the hole, or in the plug, and you don't have to stand up and use your detector to do the same thing. Harbor Freight has one under $20, much cheaper with their always coupons. On the forums, you have to spend over $50, closer to $100, for a bunch of features, you don't really need or use much. Same applies to digging tools, Walmart has some decent ones for under $10, that held up fine here. Just a Fiskars sod cutting knife, and a garden trowel for my sandy soil. Might need something heavier for your soil. I used other tools to deal with roots, or prying heavy/strong things, some people expect one tool to do everything. The popular forum digging tools start at $50, and don't do it all anyway. Basically, start off cheap and simple, and get what you really need, don't let them spend your money for you. Most of the time, you don't need the expensive stuff. Batteries... Well, you know some electronics, so you'll sort of get the idea, when you read some of the claims and suggestions. I used rechargeable, but use them in most everything anyway. But they make sense, than spending $5 every couple of weeks, just to throw in the trash. My detector takes 8 AA, and alkaline last about a week longer than NiMH. A decent charger will make them last years. On the forums, you will hear about people's detectors working better, going deeper on fresh, premium alkaline, and use nothing else. Change them at half discharge. I know there is a voltage regulator in there, it's a sensitive device, needs descent power management, to function accurately and consistently, through the battery life. It be a poor design that only worked great for 30 minutes, and degraded as the batteries are discharged. Starting out, alkaline are fine, should last a good while, won't be out all day. I usually didn't run mine more that 2-3 hours a day. Mostly only had mornings, before it got hot and sweaty, fun and adventure, starts to feel more like work.

Basically, you can get all you need from reading the manual that comes with the detector. I don't usually read manuals, until something doesn't go as expected. But I did eventually read my manual, wish I had from the start. You really need to understand the options and settings, and what needs adjusting. Takes a few tries to get it dialed in to the soil you are hunting in. And when you travel, you need to make some adjustments as well, for different conditions. It's sensitive, and needs fine tuning, to get stable usage. you sort of need to find the spot, where it's not beeping all the time, but not quiet too much either. Sort of why I suggested starting in your own yard, you can stop, read the manual, go online, anytime, as long as you need. Can wash your hands, get something to drink, relax a little. Just goes a lot smoother.
 

Mickster

Well-Known Member
Most Helpful Member
Thanks once again Harvey,
most of what I will be doing is probably the beach, so I guess a trowel (like this below) and a mesh sieve will be sufficient, along with a trash bag.

The Amazon link above shows what is in the bundle and that includes a pinpoint tool. So, for that price, it looks like a good deal.
 

HarveyH55

New Member
Not sure how useful a trowel would be on the beach, never detected one. The nearest is about a 45 minute drive, well probably longer, if I drove the speed limit... I stop going a long time ago, they installed parking meter. Use to be luck, getting a parking spot close to the beach, might have to walk a block or two. Just didn't seem right, to have to pay, nor was it fun watching the clock, or having to make a special trip, just to feed it. I only paid on time, never went back since.

Most of the beach hunters use a scoop, about a gallon jug sized shovel, with holes in the top, back. Basically, you use standing up, just tilt it, sand falls out, everything else, larger than the holes stays in the scoop. There are a lot of DIY designs available, some even use plastic jugs... There are quite a few models for purchase, seem kind of pricey though. Our beaches are all sand, but I know there are beaches with rock and gravel mixed in too, which would tear up plastic pretty quick.

Your bundle comes with a coil cover. Check the price of a replacement coil, and that cover will look real attractive. But, many of the beach hunters complain about sand getting in, the hassle of removing the cover, to empty it out occasionally. Mine come off fairly easy, but I cheat a little. I was given a little plastic tool, along time ago, for opening electric cases. Not sure if it has an official name or anything, but it works great for a lot of stuff. Once you release a couple of tabs, it peals off easy. I've got 4 different size coils, $80 to $120, each. The stock coil you get will be fine for most work. I'll warn you about the really coils... That's a lot of copper weight, plus potting, and it throws off the balance quite a bit, noticeably. Most coils, you can just swap out, no big deal. The big coils need some adjustment, basically, I shorten the shaft, swung closer to my feet, little awkward. I got the big coil, because it will cover more ground, but in my case, they also reach deeper down. I had the silver bug, after finding that first silver dime in my backyard. Figure the heaver metals just settle deeper in the sandy soil. Yeah, I dug up my yard many times, probably still more stuff to find. You never really get everything in a single hunt. Which reminds me... Before you fill your hole back in, always re-scan it with your detector. There are often multiple items, specially, if your machine tells you coin, sounds like a coin, but all you found was trash.

That orange pinpointed, they referred to as a 'carrot', when they first came out. Their original was black, and cost $127.50... I used the Harbor Freight, cheap, but good enough for my needs, plus it was simple to modify some, all through hole, simple circuit. Replaced the button with a rocker switch, stays on while in use, don't have to hold the button. Changed the beeper, to a vibrating motor, thing was loud. Installed an NTC thermistor, 180 ohm I think, low value, it was unstable in the heat, but calmed it down. Yours does all that stuff, and more, automatically, several mode choices. Unfortunately, think it was just one button, you had to click through, until you got it set. Not sure if it remembers, or you had to do it, every time you powered up. Could be thinking of the original. Should be nice though, just don't lay it down and forget it some place, it's got some value to it.
 

tvtech

Well-Known Member
Most Helpful Member
I've circuit diagrams somewhere here from Practical Electronics, ETI (Electronics Today International), Elektor and many other mags dating back to the late seventies and early eighties. PCB layouts and all. Working designs. For hobbyists.

I never got round to building any of them though.

tv
 

Mickster

Well-Known Member
Most Helpful Member
Hi Harvey, great info again.
The idea about using a trowel and a sieve, was that the target hole could be scooped out and dumped into the sieve, letting the sand fall out and leave trash/goodies behind. Since some goodies are non-metallic, there might be something decent, along with a ring-pull/bottle-cap in the same hole.
Also, imagine something like a fine chain. From looking at the sand scoops (saw Gary Drayton, from The curse of Oak Island, using one on his Youtube channel) the holes are generally quite large and a fine chain may likely be prone to keep falling through those holes...a sieve may be better at catching that one time.

I know you said to keep checking the target hole even after finding something, so that's a good tip.

A scoop wouldn't be a problem to fabricate, I can do one out of steel (which would be ideal for a beach :rolleyes: ) stainless or aluminium, and I also saw some ideas using plastic feed scoops, as well as PVC plumbing fittings. Also have some HD-PE (currently looking at recycling) which can be used, but am hesitant about using any form of plastic because there is far too much of it in the ocean already.

The coil cover will definitely be used, since it will also offer a bit more protection from knocks and bangs - we have a 1 car per household rule, but unlimited motor bikes/mopeds (up to 150cc). The wife has the car and I have the bike.

Looked at a couple of teardown videos of the Garrett CarrotTM and noted that it's mostly an SMD assembly, with what looks like a uC in there. It remembers the last setting used on the next power-up and can be adjusted, sensitivity-wise, on the fly - just press the button for a short time and it nulls at that distance. I will attach it to myself with a springy key keeper.
 

Mickster

Well-Known Member
Most Helpful Member
tvtech you changed your avatar - is that you and?

Looked at a few different circuits, mostly old BFO stuff. Thomas Scarborough published some and also published PI circuits IIRC. May look at building a PI circuit soon.
I came across this BFO one:

The circuit was referenced in the comment section of this Youtube video:

I built it on a breadboard to see if it worked, cos you know Youtube, and it does.

ETO BFO.jpg

The coils came from an old automotive ABS control unit, so they are pretty closely matched. Just laid a couple of brass strips across one, to null the circuit. Pass a screwdriver tip across the other coil and it screams like a mamma-jabber.
 

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