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Topics - woody

Pages: [1] 2 3 ... 6
1
General Discussion / GFX-7000 There is hope.
« on: June 17, 2022, 11:17:34 am »
The Chinese are pushing this GFX-7000 detector around the place, i’m going to say it as it is, the coil is crap, the bottom shaft is plastic tube and useless and it is as noisy as all hell. Upon inspection it is an attempt to clone a GPX-4500, some years ago the Chinese managed to get hold of the designs of the 4500 and other things by infiltrating the company by some sneaky means.

Now for the good news, apart from the Chinese screwing up the design, i worked on one of these clones and made it run perfectly, initial tests indicate that it works just the same as a 4500. looks like i will doing some tests out in the field.

2
Pushing the technical limits. / Getting every last scrap of Gold.
« on: June 13, 2022, 09:53:26 am »
Is it possible to get every gold nugget that lay underneath one sweep from a metal detector coil?
The answer is definitely no. A large coil will do well in detecting large deep gold but it will be really struggling to pick up the small gold at moderate depth, same is for trying to detect large gold nuggets with a small coil. On top of the coil issue there are detector issues with transmit pulse length, repetition rates, sharpness of the ground balance circuitry, time delay on receive turn on, ground noise and decay rates. Then there are other factors on the technical design of coils and detector electronics. The single biggest issue is to be able to retain all target input signal without it being obscured by noise and thus lost. There are methods that the current detectors do not have in their designs, it is difficult to discuss all the ways to do this on a public forum as publishing yet to be patented discoveries is commercially unviable if one i trying to run a business in making detectors better.    This is our newest upgrade for SD GP GPX detectors, wait for the test video’s.

3
Any of the current DD coils have different values in the receiver and transmitter coils, the higher impedance that the receiver exhibits unbalances the detectors cancellation function in cancel mode and causes a mismatch in the detector preamplifier stage resulting in less depth, greater noise pick up and increased responses to ground noise. DD coils if redesigned properly can be a game changer.   i bet there will be new DD coils out in a couple of months. not by me..

4
Technical / A common fault in nearly all Pulse Induction detectors
« on: March 07, 2022, 09:17:06 am »
There is a subtle design anomaly in just about every pulse induction detector that can limit the depth capabilities of the detector. Nothing in this world is perfect but with some added engineering the depth problem can be greatly reduced.

5
Noisy coils and how to repair. / Why is my coil noisy?
« on: January 22, 2022, 05:14:01 pm »
Most likely it is that the carbon, and or graphite paint the shields the coil windings have worn through. This is very common and best explained with pictures and video.

6
Technical / GPZ7000 handshake coil work around.
« on: January 11, 2022, 11:52:11 am »
There are a couple of ways to use different coils if you really want to do it, cut the chip board from the coil plug and solder it to the inside of the detector, thus it will function on all test or after market coils. In the mean time I have been working on a way to have the detector ignore the handshake protocols, there has been some success and I will update as I progress.

7
General Discussion / GPZ 7000 and coils
« on: December 25, 2021, 11:24:15 am »
Here is a warning about trying after market coils on the GPZ 7000. Don’t do it! Any fault in the coil can destroy the coded handshake ic chip inside the detector, Minelab have a way of knowing (imho) that an after market coil was fitted by the nature of the damage, this has been told to me from prospectors that sent their blown up detectors to minelab to be repaired, I was told minelab refused to repair the detectors, so…In my opinion it is not wise to play around with this part of the detector, it can be a very expensive exercise.

8
General Discussion / EMI that noise that hides gold targets.
« on: December 22, 2021, 11:20:11 am »
There is nothing worse than trying to use an unstable metal detector that is making noise due to EMI, I have discovered that a rectification issue is embedded in nearly all pulse induction detectors that use semiconductors in the back emf blocking path, but there is a problem. As all these discoveries are hard won battles I am not going into technical discussion in order to hand over valuable discoveries and information to other parties for free. They say that others that copy your work is a form of flattery but it’s not, I have seen and heard that others tell customers that I copied their work and one in particular was telling people that he taught me everything that I know. This guy is a wanker, he was calling me up trying to milk me for information on detectors, he would say that it was only for his personal detector….lol anyway this is why I do not tell anyone my telephone number..as it invites another form of EMI. That being said, we currently have an ex Minelab detector tester using our newest mods and his words are, “ this is the best detector that I have ever used” but he did say that EMI was still a big issue, so over the last four months I set out to try many different methods to remove EMI and retain greater sensitivity and depth while improving the ground balance accuracy. Well, I succeeded on all fronts, these improvements are for the GPX 4500 and 5000 but will also work on other pulse induction detectors. It is about time that I go out over the old detected gold fields and find gold that other detectors will never be able to find.
This is going to be like 1980 all over again. I’m excited.

9
General Discussion / New mods as of December 2021
« on: December 14, 2021, 09:10:09 pm »
A lot of hard work has gone into a full blown components upgrade and new additional control boards, this is really not for hobby detectorists as it costs a lot to do, but is aimed at full time professionals that need to find gold every time they go out. Tests on hot ground at Red streak gully in Dunolly central Victoria show 17% more depth over standard detectors using 17" coil on 6 oz target. Expect to see me out going over as much old ground that I can.

10
Tested today at Red Streak Gully in Dunolly on red hot ground.
The newest upgrades in a GPX detector.

Using 17" coil and 6 Oz test nugget I can say that we gained 17% greater depth compared to a stock standard GPX detector. There is still more to come but it takes time.

11
We are starting to run some new boards out that have a far greater performance on tiny gold and big deep gold using large coils. The new boards have a set of very fast low noise intermediate drivers added, inclusive of new components to give a different attack and decay phase shift that helps greatly with the ignoring of hot rocks.

This allows far more gain to be used while at the same time reducing the response to hot rocks and ground noises. The new settings allow the use of a large mono coil even in normal timings as to be adjustable to the point where it is far less sensitive to ground fluctuations and the dreaded hot rocks.

Now just because we put a turbo charger on the V8 it does not mean that you can wind everything full and go hoon around in the rain, you just end up doing wheel spins and getting nowhere fast.

The type of ground is the main thing that you have to deal with, red hot iron stone ground means to reduce the gain so that the input circuit of the detector is not overloaded by a huge ground signal, reducing the gain and the variable frequency control helps control the noise, 

In mild ground such as pipe clay and some river banks it is possible to run the gain nearly full on, this has not been possible before as the earth field creates too much of a weee wooo sound when moving the coil up and down a river bank.

As the biggest deepest gold is more likely to be found in normal timings the upgraded sub board allows the use of normal timings in most circumstances, even with a 24 inch coil. Tiny gold such as spurry reef or 0.005 gram bits are easily detected in Enhance mode with a small coil, running the variable frequency around 200 or more with the gain set as to allow perfect ground balance is outstanding. My own testing with a mono 10 x 5 coil on a 0.005 gram gold can actually cause an overload signal on the detector. This tiny gold was detected out to 8 cm.

The real testing should always be carried out on the ground that you intend to detect, bury a target such as a gold nugget or melted aluminium and try to get it so deep that you can just detect it, experiment with settings and coil sizes as to get the best depth without making the detector unstable and noisey.

After playing with the detector and if you get confused with the changes, its very simple to reset the detector by turning the detector off, holding the power switch down until it goes dee dee dah and turning the control to reset all, then turn the other control to do the reset. It is as basic as it sounds.


12
It is the 24th of December 2019 so my the time we have built up more circuit boards we will be referring to the new board for SD GP GPX detectors as the 2020 upgrade. Older detectors can be made just as good as, if not better than the newer detectors by swapping out older components and replacing with cutting edge technology as it is made available. I added a new board to an old 2100 detector and it can detect just as good as any of the newer detectors as long as certain criteria are met, timings can be made adjustable and the variable gain board placed just after the input stages makes a huge difference to ground noise suppression and small and large gold detection. When the weather cools off I will be making some proof of concept video's.

14
New Detector accessories / New Wireless headphones with no delay.
« on: June 14, 2019, 02:15:48 pm »
These will work with any detector.

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