Steve Herschbach

https://metaldetectingforum.com/showthread.php?t=50864 One problem I can anticipate is White's boards do change over time as component availability changes. The ultimate source for this sort of info is the Geotech Forums

Circuit diagram for Surf PI - probably an earlier version but it might help. Another one here plus many more More schematics here.

Great price if from legit source.

If the reset cleared things up and then it got progressively worse again, I would be exploring the ground tracking options like fixed.

Seems like a lot of us make one of these sooner of later. Lots of fun because it is a small, containable project. Looks like a nice little unit!

Does not sound right Steve. Have you done a full factory reset?

some background.... January 22, 2014 Light Detection And Ranging (LiDAR) July 12, 2018 Just Discovered Lidar. Amazing Insight Into Old Sites.

Welcome to the forum! And thanks for taking the time to register and post!!

That's a good way to go in my opinion.

So are you saying you made that out of melted scrap? It looks manufactured.

Perfect cross link - thanks! Instead of posting the same post on multiple forms this is the way to do it. Create a new thread in the most appropriate forum. Then, if you think another forum is also appropriate (it happens) just copy the first thread link and paste into a new thread as Cal has done here. That creates the cool little link back box you see above. I do this with my own posts if I feel it appropriate. If others post the same thread on multiple forums, I usually delete the duplicates and create temporary 30 day cross links. This method works better. Desert prospecting can be downright scary at times - I have already learned my lesson there!

I enjoy the DetectorComparison videos, he does a good job. Some not new but solid tips at the end of the video.

You don't need to email or anything, just download the pdf and print. The whole "I will mail you something" thing was a year ago. I have edited Scott's original post to reflect this.

Good for him, congratulations! Anyone know who won the December Find of the Month? Link? Edit. Found the link but they skipped December? Interesting the Find of the Month is administered out of the Dubai office?

As has been noted elsewhere one might expect some new GPZ 19 coils to be getting sold as used soon as people get this deal and then some of them may sell the big coil to help lower their "all in" price.

Adrian Harris Published on Feb 17, 2019 - On our 4th dig at K C Rallys up comes a William 3rd silver hoard 51 in total well done Garry next step reporting the find to the Worcester FLO.

Several U.S. dealers are advertising a free GPZ 19 coil with GPZ 7000 purchases though 4/15. I have not been able to find this on the Minelab website so maybe U.S. only? So there is the forum "mission". Is this promotion good in Australia and the U.K. etc. or just something out of Minelab USA?

That is weird. My first thought since you say it is hardened is that it is some sore of shear pin beaten beyond recognition but I really have no clue.

From Facebook....

There is nothing wrong with the X-Terra Prospect Mode. In Oz it is just more of a VLF versus the PI/GPZ side of things. I ran a Gold Bug 2 and Gold Bug Pro on hot ironstone ground in Oz with no real issue. I can get them to do the job but you may only be talking 1/3 or 1/4 the depth you might expect in low mineral ground. Personally I would not want to hunt down under with less than a good PI. But if a VLF was all I had I could go find lots of little gold with it. The PI guys leave that all over the place though the SDC is amazing and is getting a lot of that now. But who wants to go to Australia to hunt tiny bits?

Yeah, how about those!

The website Reference Library has many free books that go into detail about how and why metal detectors work. A good place to begin is How Metal Detectors Work by Mark Rowan & William Lahr - Originally published by White's Electronics as a booklet P/N 621-0395. Basic but rather technical information on how induction balance and pulse induction metal detectors work. The key for people who want to make a metal detector is the Geotech website and forum. This page has do it yourself projects. You can easily make a simple metal detector. Making anything I would want to use would take a skilled person. I am not but I think I could tackle it so I am sure you could, but I am not into that. I like to use what people lots smarter than I can make!

Here is a summary I posted back in 2002 that must have been ok because it got quoted in at least one patent I have seen. Hi Guys, Here is something I wrote in response to a question on the Alaska Gold Forum. It is of course just my take of what I've read in lots of places, including this forum. I'd like to use it on my website, but I'm asking for your expert advice on anything I may have oversimplified or am simply wrong on. The main goal was to try and keep it simple, however. Here it is: What follows is a layman's description of the technologies involved. I'm trying to do this in as few words as possible while hopefully imparting some of the general concepts accurately. There are two types of detector technology currently available for hobby use. Today's metal detectors are basically radio transmitter and receiver devices. The first, Induction Balance (IB) technology, relies on a transmitter and receiver coil operating simultaneously in a state of electrical balance. Any conductive or magnetic object entering the field disturbs the balance and generates a signal. Plus, eddy currents are induced into conductive targets creating a detectable signal. Most people refer to these as VLF detectors, but all VLF means is Very Low Frequency and refers to a particular subset of IB detectors. Some detectors referred to as VLF today are actually operating in the LF (Low Frequency) range. Induction Balance is more accurate as it refers to the technology, not just a frequency range. Older style T/R (transmitter/receiver) detectors are also IB units. The second, Pulse Induction technology, has been around a long time and every one of the major manufacturers makes a PI machine. There is the Fisher Impulse, Garrett Sea Hunter XL500 Pulse, Tesoro Sand Shark, and White's Surf PI. These are all units designed for use in saltwater/black sand beach environments. Simple Pulse Induction units use a single coil to alternately transmit and receive. The transmitter segment creates an electromagnetic field that induces eddy currents in conductive targets. These eddy currents actually take some time to ''decay'' and so when the coil switches to the receive mode it picks up the weak eddy currents just induced in the transmit mode. Induction balance units constantly bathe the search area in an electromagnetic field. Smaller items can be detected because of this, but the IB units also detect more ground mineral. If there is too much ground mineral it makes it hard for the machine to detect the target. IB detectors have superior target id capabilities as they use a combination of the eddy currents and the electrical imbalance in the search field as information to identify targets. Pulse Induction units use eddy currents only. When the transmitter shuts off the electromagnetic field collapses and so there is only the weak eddy currents to work with. The good news is that eddy currents flow much longer in metals and for a much shorter period of time in ground minerals and salt water. A delay between the transmit and receive modes allows the eddy currents in low conductive targets to decay enough they will not be detected. The stronger eddy currents in more conductive items is detected. This makes most saltwater and certain mineral environments almost invisible to PI detectors. It also means very small targets are harder to detect as they cannot hold an eddy current for long. Since PI units have less information to work with than IB devices they have little or no discrimination capability by comparison. Although common PI units do better with certain mineral environments that IB units they still can be affected by mineralization. By using multiple pulse periods and using the information gained from some of the pulses to modify the others, Minelab developed ground balancing pulse induction technology. The called this MPS for ''multi-period sensing''. This allows the Minelab units to work in mineralized soils other PI units would have problems with. This in turn also allows for higher powered units with better sensitivity to small gold. And so the Minelab SD/GP series was born. The Explorer, Fisher CZ series, and White's DFX are all Induction Balance units but are working with information received from multiple frequencies. A very rough generality is that low frequencies detect larger objects better at deeper depths. Higher frequencies tend to hit smaller items better at shallower depths. Multi-frequency units attempt to use information received from multiple frequencies to achieve superior detection characteristics including better target id. Most of what multi-frequency is about is how many frequencies are received and compared, not how many are transmitted. But the key thing is that there is always a signal being transmitted and received simultaneously. The DFX is my favorite example. It can be run in 3kHz only or it can be run in 15kHz only. Or it can be run at both 3kHz and 15kHz simultaneously. Multi-frequency technology is just another type of IB technology, and they are not PI units. Steve Herschbach