moxford

Cleaned up a bunch more trash last night; I still don't feel that I can "trust" the iron discrimination. I know it's an inexact-science to being with but I dug up a 4" chunk of an iron bar, ferrous, at 1" because even in iron-disc it still spiked the VCO up nicely (expected due to big target, close, but expected it to be disc'd out.) I've got a really nice diverse test-set now. I think it may be close to time to start doing some really solid controlled side-by-side testing. Excepting the discrimination I think I'm about comfortable enough to hit some gold-areas tomorrow. Hopefully, and with a ton of luck, I'll have a couple more test-subjects for my collection! > Rock on! -mox

Wait, does this mean we cannot talk about "those other brands" now that you're entangled in affiliation?! Aiiieee....

Congratulations!

Thanks everyone. Great info. The goal is, yes, to understand enough to build my own (more than just a toy) and really understand the challenges and technical limitations of the current state of the market. Time to start tinkerin' ... =)

So it seems that we have some very interesting people on this forum with regard to really knowing about MD-tech. Where does someone with a solid software (but very little electrical) background start? I understand the 20,000' theory level for some of it, but without the EE background it makes it difficult to put into practice. So I'm working on shoring up my EE side. Are there are canonical/seminal books on learning VLF/PI technology ... or just Google around? I've been reading the GeoTech site (which is awesome) but I'm not sure if the 'net is the most efficient place to start or if I should pick up "book X" to really set a foundation. My "real job" pays much better but this stuff is far more interesting. =) Thanks! -mox

Oh, just so everyone is aware: that post was meant to be lighthearted and not "down" in any way! I knew going into it I was in for a lot of digging and learning and confusion. Personally, I prefer the "more trash." It gives me more chances to hear "what is what" in a smaller timeframe. It's easier (for me) to then correlate the various sounds in my head and try to make sense of it. And it keeps me from getting bored or running out of space to detect in. Also, I now have a good set of "distressed targets" (eg, rusty garbage) in my collection to then resample at home. The mineralized stuff I was seeing was when I was in Low GB, and they (the rocks) would fire it off. They respond to a magnet, too. When I moved to Med GB they disappeared. I searched in all-metal until I hit something, then checked it (or tried) with discrimination. Whatever ground I was in for this park, I pulled out a clad dime at 3" and it had so much reddish-iron color bound to it that I thought it was a penny at first. I found what also seems to be a highly-ferrous round target about 1/16" in diameter which looks (to my highly un-trained eye) like a little ball of rusted iron ore. /shrug Thanks for all of the information about the GB2 tonality. I'll have to think on that and compare it to what I heard (especially as I go back over the junk.) I figure there's a ton of nuances to pitch, duration and amplitude that I'm just not hearing because I'm new so it'll just take time to tune my ear. It was still fun!

Okay, yeah, I took, as a first outing, a GB2 to a public park and a tot-lot for about 1.5 hours to practice with the 10x5" coil (all I own.) First target out ... a hot rock. Uh oh. Second target out...darnit ... I can't nail it down... what the heck ... turns out it was 8" of 16ga steel wire. Grr... Third target ... oh yeah, I have discrimination! Target! Discriminate ... solid clean spike. Discriminate means no iron, pull it up ... rusty nail. *boggle* Fourth target ... okay, signal...discrimination ... multiple-spike flutter ... due to last #3 target that must mean it's NOT iron since #3 was .... rusty wire. *boggle* Things I learned which you all probably already knew: 1) I have no idea what I'm doing. 2) Manual GB is a lot of work. Doable, but still a bit of work to do it over and over and over. 3) The park I was in had hot-rocks. Granite-looking nodules of evil. Everywhere and at all layers. This is just obnoxious. 4) Iron discrimination either doesn't work, or more likely, I'm going about it all wrong so I need to work on this. 5) This GB2 is insanely sensitive. I chased a signal in the sand for almost 10 minutes only to find out it was, literally, the platinum puck off a spark plug getting kicked around. 6) At 12 cents clad per outing I'm never going to pay this thing off. =P (I bought it for the gold fields so this is very tongue-in-cheek.) 7) The mosquitoes are active now. They're huge and hungry. 8) Digging everything stinks when you're not allowed to actually dig. See #1 and #4. 9) Having a pointer (TRX) is nice. In trashy areas it's annoying to get it out, put it away, get it out, put it away, get it ou... 10) All pinpointers should have headphone jacks. Talk about drawing attention... 11) Foil + lawnmower = no fun 12) It's was a pretty darn good time. Well, except for the mosquitoes. I cannot find any YouTube videos or anyone on "how to interpret the Gold Bug 2 tones." Even over lots of trash and some test targets it's not quite making sense. Anyone have any good resources on learning those tones? Especially the discrimination tones? On the plus side - I cleaned out a bunch of rusty trash, beer bottle caps, wires and such so the park it 0.00000001% cleaner.. Rock on.

Does anyone use the their detector as a zone-location aid before working a pan/sluice/highbanker/drywasher? Or are the nuggets stand-alone and not an indicator? Thanks.

So if you're looking for areas to work with a pan/sluice/highbanker/etc are you using the GBPro or the GB2 for the increased sensitivity? While I understand the "book difference" between the two I've never used them side-by-side so i don't know just how big (or small) that delta in performance really is. Digging through reports and spec and white papers and demos and YouTubes and such only gets me so far - which I why I'm so appreciative of all of you taking the time to help with real-world side-by-side experience! I have a GB2 en-route right now. Snagged it for a good enough price that I should be able to resell with no issues (and hopefully a small profit) so then it becomes ... GBPro or wait for the F19? =P

Probably the signal processing - the detector box doesn't know how to interpret the signal off of a triangular "coil" vs a "square coil" vs an elliptical coil. Or worse, one which is all deformed from being shoved into a rocky crevice. Just a guess.

Hi Ray, what makes you say this after having used the GB2 for so long? Thanks!

I recently finished Mary Hill's book "Gold: The California Story" so your timing on this is perfect as I was just looking for something new! Thanks!

Hmmm, with a PI machine you're energizing the coil to create the field. When you turn power off that electromagnetic field collapses on itself and generates its own electrical signal. (Faraday's Law) That's why you need the delay, to let that current from the induction-field collapse to be handled (at least, that's my understanding of it.) It'll be interesting to see if they've found a way to either attenuate that current, or somehow protect against it (which, IMO, would be the more interesting option since that has some really wide ramifications into other fields!) Hope you get one soon and can fill us in!

Oops, sorry Steve! I was thinking of Bearkat's videos. I've done so much research and I've seen your name over and over on various forums I somehow thought that they were yours. Again, apologies. Deathray, I am new to prospecting with a detector. I've done some panning and sluicing. The primary reason for "waterproof" was naively thinking I could use it in the rivers as well as IN the surf (and, for the cost, I didn't want to risk hundreds of dollars on a single oops-move in either environment.) The Garrett stuck out as one of the only one which would work in either environment with the added advantage of folding up a bit better for backpacking. My perspectives have changed a bit since the beginnings of this thread, but I'm probably over-thinking things at this point. and I should just get a GBPro and resign myself to missing the really small stuff and that I'll have to not be a klutz. =) No, I do not have great property. Or ay property. I did go ahead and go GPAA just so I had SOMETHING to work with, and I've spent a lot of time learning the BLM LR2000 and Geocommunicator system so I can try to find open areas to check out (as well as respecting other's claims.) I may very well end up at the river in Auburn (incidentally the area where I first learned to pan and sluice many years ago) but I do not hold any special expectations ... those grounds have been hit so hard it's unreal. I've spend a good number of hours as well reading up on the old Mother Lode towns, sites, and geography (including all of the Smartsville-block theories and lode topologies.) Most of it's all private land with no access. But in the end ... it's where you find it, right? =) I hold no visions out finding something special that all of the thousands before me, including the professional geologists and massive mining conglomerates, have somehow missed. I will hold the skunk close, embrace the "it's going to be lots of work no matter how you slice it" and just enjoy my time outdoors and out of the Silicon Valley. And, worst case, hey .. I'm helping clean up the rivers.

moxford is equivalent to rmills since my name is Mike. The system apparently defaults to your username - I have not looked to see if I can change the display name. =) Due to there being multiple employees named "Mike" (5 out of 15) we all had nicknames. One was simply "M5" because he was the 5th Mike to join. moxford is my email and it just stuck - there's never any confusion on "which MIke" in conversations. It's often shortened to just "mox". I guess, as nicknames go, it's not too bad. It's been with me for years. http://www.linkedin.com/in/moxford is me. Probably too much information but hey - you asked! =) Back on topic.. More good info, thanks. Steve, your videos were some of the ones which really turned me to the ATX. Ray, your use of the GBPro surprises me because I've read time and time again "go GB2, go GB2." Everyone fixates on the 71kHz of the 2 being so much better and if someone wanted a VLF for discrimination they would use a better VLF than the GBPro. They probably just don't drive them as well as you do or they're parrotting others on the 'Net. Awesome to hear it directly from someone using it at least remotely close to the same target zones as I'm looking at. I have bids out on EBay for a GB2 ... I kinda hope i lose while I reconsider! /laugh -Mike

If you don't mind my asking, what led you to the GBPro instead of the GB2? I've heard that the GB2 is "better" for small gold, but perhaps you're using the iron discrimination? Thanks!

Thank you to everyone for the input! Ray, huge thanks for dropping by with such a great post. I'm down in the SF Bay Area and, as you can tell, just getting into things. I have no idea what I'm actually up against so such an in-depth answer really shines some light on it - in some ways more so than the hundred-plus pages I've been reading off of Google. Also, your information about the sub-grain quartz is excellent - while dredging is shut down and highbanking isn't allowed anymore (for all intents and purposes) there's no regulations that I can find against sluicing or drywashing. I am surprised to hear that the ATX didn't hold up for you. In many of the videos online (including the ATX vs GPX 5k shootout) it seemed to do quite well (and being that it's a PI I wouldn't expect much issue with soil.) Interesting to hear that you think the ATX isn't quite as good as your 3k but it seems to stand up well to the 5k? Is the 3k better for the type of hunting you do compared to the 5k or is it just "internet skew?" =) Thanks again everyone, and especially to Steve for being incredibly active, helpful and generous with his time on the many forums I'm reading (including his own)!

Gotcha, thanks. I was hoping that the issues with hot-ground would be the same as surf (eg, both just needing a solid dose of PI radiation instead of VLF.) If it's really that varied then it opens up the door for VLFs more. I've been eyeing the V3i in prospecting mode @ 22kHz - not quite GB2/ATGold but probably good enough without getting uber-specialized. I am not looking for SCUBA at this time - I sold all my gear when I moved back to the States ... just playing with mask+snorkel and peace of mind for splash damage in the rivers, surf, or rain (because I'm one of those nuts who enjoys the rain.) Thanks for feedback - will keep looking!

How bad is the mineralization in the California Gold Country region? I cannot seem to find much information on it, but lots on the Arizona desert region. Should I interpret this as mostly VLF territory or just a lack of postings about it? I've been considering the ATX for the PI capabilities but if that area can be handled by a good VLF (GB2/V3i/ATGold) that may be preferable. Priorities for me: 1) Waterproof (I used to scuba so it may see submerged use) 2) Small-ish nugget detecting in California (primary reason for getting a detector in the first place.) 3) Surf detecting (again, see #1 just for peace of mind =) #1 is the killer - really the only other option there is a 3030 (VLF). Things like the ATGold aren't recommended for the surf and the GB2 isn't waterproof. (I used to scuba and am looking at mask+snorkel as well.) It really sounds like it's right up the ATX alley but I'm open to other suggestions. I wish Minelab would hurry up with the SDC2300 - not much info on it out there right now! I don't really want to run 2-3 separate detectors but ... /shrug. Might have to, but I'd strongly prefer to just learn one machine really really well (for now.)