rumblefish

So does this make your DIY ATX project redundant now? You didn't really have to explain anything, Steve. Just the fact that you bought one speaks volumes. I first came onto this site because I was trying to decide on a detector to buy, having never used one before, but having reasonable experience of prospecting. My biggest criteria was efficiency and physical size/weight, since I go everywhere on a motorbike. And perhaps that it would also be waterproof. After speaking to you I went with the SDC 2300, and it's a fantastic machine. I haven't found any gold by detecting yet, but I don't think any machine would find the tiny pieces I am recovering using the sluicebox. But I know that when I do eventually find a spot where the gold is larger in size, the SDC will find it, no problem. A GPZ 7000 would be no real use to me right now, even if it was the same price as the SDC 2300, since I can't carry it and I'm not hunting in the middle of a gold field. But if the GPZ 7000 does on big and small gold what it's little brother does on tiny pieces of metal (my only finds so far, unfortunately), then it must be a very impressive machine. I'm sure you will find some nice gold with it. Thanks as always for sharing your knowledge and advice.

Kryptonite

If you look at this intro video on the Minelab site, at about 01:20 into the film, there is a diagram of the new DOD coil. Basically you are getting a DD coil with an overlapping oval coil in the centre. I imagine this centre coil works very much like the coil on the SDC 2300, with the added benefit of the signals picked up by the DD coils on either side. I'm not an engineer so I have no idea which coil, or what percentage of signal from each coil, is intepreted by the detector in its different modes, but on small gold I would suspect the GPZ 7000 runs like an SDC 2300 with the benefit of some extra signals from the DD coils, pushing it's performance to about 15% more than the SDC 2300 in best case scenarios. In real life, I expect the two perform quite similarly on small gold. Where the GPZ 7000 has the advantage is the bigger and/or deeper gold because the design and size of the coil, and the signal technology behind it, is better suited for finding that gold. But that's me guessing. Unless Steve or Jonathan can run both detectors side by side and observe their capabilities on test nuggets in different soils, it's hard to say.

I'm working on something along his route for the SDC 2300. Once I have it up and running I'll post on here.

I suspect he's wearing that shirt more because of Didier Drogba (legendary Chelsea striker who hails from the neighbouring Ivory Coast) than Chelsea per se.

One stupidly obvious thing I noticed... why didn't they make the handset collapse like on the SDC 2300? It would make the whole thing fold down to a much smaller size. EDIT: Actually thinking about it, if the GPZ was fully collapseable, Minelab would be cannibalizing their own market, since looking at the field tests, the GPZ out performs the SDC in all areas except portability, price (I assume) and performance in water. It also doesn't take standard batteries from what I can tell, though the lithium cells should perform better than Ni-Cads.

Thanks Steve. This technique looks very interesting. A lot of the places I go panning have large areas of flood plain gravels that are far from the river. Or located in dry areas where the water runs so slow a sluice box won't work efficiently. This ground scanning tip could be a handy thing to try. The problem I have found so far is that the gold is at least a foot below the surface rocks (left by the last big flood several years ago) and is often so small even the SDC 2300 or a pinpointer won't see it. I need to find an area where the bedrock isn't so deep so that I don't have to clear so much overburden to get to where the gold is trapped. I know from finding small pieces of shot that if there is small gold within a few inches of the coil the SDC 2300 will pick it up easily. It's just a matter of digging down to the level where I can get the coil in range of the gold.

Your best bet might be to see what the Nokta people come up with. From what I've seen of their response on these forums, they could have one ready for you next week!

I actually find myself using the green leds on my SDC 2300 quite a lot. I know as a system it is not exactly high resolution, but it gives my ears a rest and is pretty good at indicating when a target is close. Maybe converting the sound waves to a high quality visual representation would be an interesting way to go. Then you can get rid of the headphones altogether.

I guess the main problem you would have is connecting the speaker to the weird headphone port on the SDC 2300. Or do you have the adapter? Or do you mean to open the box and change the actual speakers inside? Ooo! I just became silver!

I found using a section of the edge of the coil worked pretty well to narrow down where the signal was coming from. The problem I had was that the SDC 2300 is so good, it was sounding off on really tiny pieces of metal. For example, a piece of shot from a gun cartridge that was a little bigger than a pinhead. Finding that in the dirt I dug out was the hard part. And the Garret Propointer didn't register a thing. At the time I didn't have a plastic scoop handy to toss the dirt over the detector, but I have that covered now. So hopefully next time it wont take me 20 minutes to pull out a target!

I think it depends on what you define as travelling. If the detector is travelling with you, then a padded soft case would probably be ok to protect the most important parts like the cotnrol box and the coils. If the detector is going through an airport and you can't control what happens to it, then a hard case such as a Pelican would probably be a wise option. They make cases in many sizes, and I know from various motorbike forums that people rate these very highly. They are watertight, lockable and almost indestructible.

The way to go with something as mobile as a detector is a kinetic energy or piezoelectric cell. Basically it is a cell charged by movement. So as you spend all day swinging that detector and wandering up and down a field your physical movements would be transformed by the cell into electricity, which can power the detector. These kind of cells are in their infancy, but are becoming more and more widespread. Runners can use them to charge their ipods as they are working out etc. In this latter case, I think they use sensors in the shoe which harness the pressure of the foot impacting on the ground.

Ha! Good old velcro. Has to be one of the greatest "inspired by nature" inventions.

Any decent outdoor/mountaineering store will have a raft of lightweight buckles/clips/hooks etc. Also velcro and webbing straps are very cheap to buy. Going the DIY route seems like a good idea, Steve.

I was thinking about this the other day. Frankly leads and cables are a pain, and very 20th century. There must be a bluetooth adaptor out there that could transmit the detector signal to a set of bluetooth headphones. I was also reading Scientific Amercan over christmas. One of the most exciting technologies under investigation right now is wireless charging via sound waves. There is a US company called uBeam which has created a technology that harnesses the energy of ultrasound waves. In principle this would enable the charging of small drain devices through the air. Perhaps in the future, the sounds generated by a detector could also be used to charge the wireless headphones recieving the signal.

Yes, get a scientific balance (scales), like they use in laboratories and convert the weight to grains using a conversion table like Chris mentioned above. I'm sure you can find one on Amazon or ebay.

Maybe it's not so much the rods, but the person holding them that is more sensitive to where the gold is. Curious effect anyway, and if it helps you find some gold, fantastic!

Any gold that's big enough to see makes me smile. And if it clunks a bit in the vial, even better! No, I posted about this sweet spot thing because I thought if people are pinpointing for very small gold, then maybe the probe is missing some of the targets if the wrong part is run past the nugget/flugget.

I finally managed to find some fluggets (bigger than flakes, smaller than nuggets!) that make the Pro-Pointer sound off. But running the probe over the pieces of gold I realised that there is a sweet spot on the pinpointer. In my case it is about 1cm up from the tip of the probe on the opposite side to the yellow decal. With very small gold it is the only place the pinpointer will register a signal. Has anyone else noticed this?

Amazing to see such a responsive company. Hope they have great success - they certainly seem to have started very well.

Thanks Skip!

Wow, what an exhilarating night that must have been. Crazy. Just out of interest, does anyone know what the value of each of those different coins would be, if they were sold today?

Not sure where this belongs, but I felt like posting it today. Yesterday, someone who I follow on YouTube (a football/soccer fan) was having a very bad day. One of his dogs, who often features in his video chats, had been diagnosed with cancer and he was understandably devastated. Looking at the supportive comments from the other regulars on his channel, it was heart warming to see the support for a "friend" from such a small, but close community. Visiting this board is also like that. The sense of comradeship between people who genuinely love what they do is very inspiring. I'm glad I found this little community and I would like to thank Steve and everyone else who contributes. That's all really. Have a good day everyone.

I think this observation is very true. As much for detecting (of which I know little) as for prospecting (of which I know something). Many times I have found gold in places that other people have abandoned too quickly. Another classic mistake in prospecting is throwing your tailings or diggings right on top of a gold source without even realising. You also need to research your location. Finding gold is hard work, but an enjoyable challenge. Those who do the work reap the benefits, and those who work smarter tend to reap more.