Tweet
No, it's a scam.
-
-
Re: PDC 205
I have worked with dowsing for 20 years and what I have learned that if it is used to find precious metals, like gold you are gambling every time you use it. It has worked for me once or twice to find a few little nuggets, but all in all I have 98% failure. Good guessing and reading the area will do just as good. Now for water that is a different story. I have seen and with proven results of other water dowsers in my area that are very good. They are in the 90% correct. Carl has real good info on how to build 'L' rods, MFD, and others dowsing tools. Links to the ASD and other dowsing sites. Try it out for yourself to convince yourself one way or the other. I am using a Gold Nugget Metal detector with alot better results. Rick S -
Re: Best story this year
>Looked like a first grader put it together.
You're close... a sixth grader. At least that's what Dell Winders says. He constantly brags about having a sixth grade education.Comment
-
Re: Best story this year
Hi Carl,
Good report. Just what I had always suspected about this type of gear. By the way, you forgot to add in the cost of all that hot melt glue. Must be several $ worth
Eric.Comment
-
Hey Eric...
I'm heading back to Oxford in a few weeks, bringing the wife for some sightseeing. I will then proceed to visit some customers for a week or so.
Question: has the cow epidemic shut down metal detecting? Wondering if I should consider packing one just in case I actually get time to use it.
- CarlComment
-
Re: Best story this year
Hi Carl
He must be awarded with the Nobel price for this product.
Carl my hat is off for you, I have not seen a better documentation of how low people can sink to cheat for money. Prostitution is to weak a word for this.
Thanks a lot.
MarkComment
-
Practical Guidelines for building a Magnetometer by Hobbyists
We are currently building a PPM and it starts to give promising results after months of hard work and failed testing.
Some people say that this kind of project is much too hard and too complex for hobbyists. Their reasoning is that, since the commercial products are so expensive, they must be very complex and full of trade secrets.
Others (especially those who are selling a kit or a CD) are telling you that it is a piece of cake to build a professional-grade instrument.
I do not agree with any of these two extreme opinions.
We are not yet at the end of our project but we have now sufficient proof that it was finally not an impossible task. At this point in time, I am ready to give some practical advices to those who liked to start such a project but either have miserably failed up to now (like us at the beginning) or still did not dare to jump in.
I plan to start writing a series of small chapters organized as follows:
1. What magnetometers are used for?
2. Types of magnetometers?
3. Basic physical principles used by a PPM?
4. System configurations of PPM’s?
5. Functional Blocks of a typical PPM
6. Sensor Types
7. Polarization Control sub-system
8. Audio Amplification Chain
9. Signal Post-processing and Display sub-systems
10. Tuning, Adjusting and Testing Procedures and Constraints
I would write these chapters in this sequence and gradually post them on this forum. But, before starting this task, I would like to hear from you all (more specially those silent readers on this forum), whether you could make use of those texts or you would not care at all.
Note that we have NOTHING (product or kit) to sell you (yet!), thus, we mainly count on the discussions these texts would probably start on this forum to learn even more from the experiences of others while they learn from ours.
WillyComment
-
Re: Practical Guidelines for building a Magnetometer by Hobbyists
>We are currently building a PPM and it starts to give promising results after months of hard work and failed testing.
>Some people say that this kind of project is much too hard and too complex for hobbyists. Their reasoning is that, since the commercial products are so expensive, they must be very complex and full of trade secrets.
>Others (especially those who are selling a kit or a CD) are telling you that it is a piece of cake to build a professional-grade instrument.
>I do not agree with any of these two extreme opinions.
>We are not yet at the end of our project but we have now sufficient proof that it was finally not an impossible task. At this point in time, I am ready to give some practical advices to those who liked to start such a project but either have miserably failed up to now (like us at the beginning) or still did not dare to jump in.
>I plan to start writing a series of small chapters organized as follows:
>1. What magnetometers are used for?
>2. Types of magnetometers?
>3. Basic physical principles used by a PPM?
>4. System configurations of PPM’s?
>5. Functional Blocks of a typical PPM
>6. Sensor Types
>7. Polarization Control sub-system
>8. Audio Amplification Chain
>9. Signal Post-processing and Display sub-systems
>10. Tuning, Adjusting and Testing Procedures and Constraints
>I would write these chapters in this sequence and gradually post them on this forum. But, before starting this task, I would like to hear from you all (more specially those silent readers on this forum), whether you could make use of those texts or you would not care at all.
>Note that we have NOTHING (product or kit) to sell you (yet!), thus, we mainly count on the discussions these texts would probably start on this forum to learn even more from the experiences of others while they learn from ours.
>Willy
This is great, I for one would welcome you doing this.Please care on and write it, it would sure help me out a great deal.
Thank you
DanComment
-
Re: Practical Guidelines for building a Magnetometer by Hobbyists
I'm sure there will be plenty who would like you to post this info. I think there is plenty of info out there on proton precession. I'd like to build a cesium, can you post info on that?
Thanks,
FJComment
-
Re: Practical Guidelines for building a Magnetometer by Hobbyists
It is true that there is plenty of info on PPM on the Net, however, it is usually outdated, mostly theoretical and sometimes, partly erroneous.
I just want to humbly describe the procedures we have used to get to the current status of our PPM project after meeting a lot of dead-ends in the testing.
I think the cæsium mag technology is completely out of reach from us, ordinary hobbyists. It requires the use of very specialized and difficult to find components and highly professional (expensive!!) tools and measurement instruments. I have read the story of one man who made this complete trip but it took him three years and hundreds thousands dollars to make it. He said, never again.
The Overhauser type of PPM is more complex to build for hobbyists but I personally think that it is still POSSIBLE later on.
WillyComment
-
Re: Practical Guidelines for building a Magnetometer by Hobbyists
Please go ahead publishing your chapters...
It is very interesting and will help us a lot with our ppm!
kind regards,
Willy
Click HereComment
-
Re: Practical Guidelines for building a Magnetometer by Hobbyists
Hi Willy,
I would be very interested in your knowledge and experience on the subject of constructing a magnetometer. I have never built one before. I have electronic technician level skills. I would love to try building your design. I enthusiastically look forward to any words of wisdom you have to offer to me and this fantastic group of people.Comment
-
Re: Practical Guidelines for building a Magnetometer by Hobbyists
Hi all,
I have now received sufficient encouraging personal messages on top of these posts to continue on this track.
However, I must clarify an important point. I have always personally considered that this type of project is more fun for the accumulated experience (including the bad times) than for the final result (if any). Close to my house, I have a large field whose underground is full of archaeological structures and objects (possibly even treasures!!!) and I would also like to own a ready-made instrument to start surveying but I resist against it.
If you have a deadline in your mind for the final product of such a project, I would advise you to either BUY one mag (Oouch!!) or to build one EXACTLY according to an existing description like the simple one described on the CD sold by Phil Barnes or the more sophisticated one described by Jim Koehler in his excellent document or a fluxgate mag based on Speake and Co (or Fat Quarters) sensors and described by Carl on this site. I have the proof that all these designs are not too much outdated and they are working according to their specs.
If, on the contrary, you want to experiment by yourself, go on, in case of difficulties, cry for help on this forum, I am sure that someone here (including, but not only myself) will be able to help you out.
When we started our mag project, we wanted to UNDERSTAND what we were doing and what were the critical conditions for each of the PPM sub-systems to work correctly. Remember also that our own project is still not finished even if the most critical phases have been successfully solved.
Thus, bear with me and do not try to skip steps even if you feel that they could sometimes be slowing down your progress toward the final end product.
I shall first give (or remind) you the links to two important background documents to read and study. The first one is actually the document titled “Proton Precession Magnetometers, Rev 1 J.A. Koehler” in Jim Koehler's package (It is no longer available on the web, if you want it, send me a mail) and the second one is "Applications Manual for Portable Magnetometers" by Sheldon Breiner that you can download from "http://www.georentals.co.uk/ampm-opt.pdf". You can skip the more advanced (mathematical) chapters of these documents but the rest will give you enough bread to start your trip. In my following posts, I shall sometimes refer to some data or figures from these two documents.
Take the time to read and study these documents while I start writing my first chapter.
Obviously, you could already start asking questions now.
WillyComment
-
Re: Practical Guidelines for building a Magnetometer by Hobbyists
Carl has accepted to host my document(s) on his web site as PDF files with hyperlinks to numerous web references, illustrations and exemples.
I am progressing well in the writing but I shall need some more time to ask a selected group of experoienced people to make the proofreading for me.
Thus, a bit more patience!!! I shall try to publish the six first chapters before the end of the year.
WillyComment
-
Re: Practical Guidelines for building a Magnetometer by Hobbyists
Hi all,
This is the link to a draft version of my promised PPM Guidelines.
http://perso.infonie.be/j.g.delannoy/BAT/PPMGuidelines.pdf
I have worked hard during the end of year holiday period to publish a first version ASAP.
You must understand that this is still a new born baby with plenty of missing features and a lot of imperfections. I count on you all to help me polish this work and improve its quality.
This forum will serve as FAQ and I shall insert later a special 'update history" chapter with all the important changes brought to it over the time.
The last chapters are still very much work-in-progress but I shall continue to work on it as our own project goes on.
WillyComment
Comment