MAG Building Poll

[Willy Bayot]

If you could get hold on a tested PPM design, PCB layout and associated signal processing software, would you start building one?
1. Not interested
2. Interested but not starting soon
3. I would be delighted and would start building it at once.

[ApBerg]

MAG

Hello Willy

Yes, I like to make a proton mag, if the price fair ?

Regards.

Ap

[Willy Bayot]

As fair as it can be for an amateur.

[Crowbar]

Now I'm building a fluxgate mag based on a fl3-100 sensor, but I'm also interested in a proton mag build.

[Leto]

I'm very much interested in building one ...
.. despite excelent documentation (articles by you and J. Koehler) there is always one piece missing..

Coud you throw us a bone Willy?
For example appropriate sensor parameters for your project.
Would toroid sensor also be OK?

[Willy Bayot]

There is no fixed type nor parameters for sensors to work with this PPM front-end design. It all depends on the usage you want to make of it. It is however true that there are some minimum specs to be defined in order to get acceptable results in terms of SNR.
Jim and I have published two different Excel calculators to be used to experiment 'What-If' scenarii and calculating the expected SNR, Signal Magnitude, Weight, Current,...
We first have built and experimented toroid sensors of various sizes (and weight) assuming that those were the best in terms of noise resilience and lack of directional behaviour.
Now, we are routinely using two-coil solenoid sensors which are much easier to build and accept interchangable fluid bottles. Finally, and most importantly for mobile surveys, they are reasonably multi-directional when used in our latitudes where the vertical field vector is, by far, the most powerful. It means that, provided you keep your coils horizontal, they can be put in any direction without too much influence on the signal magnitude. During my surveys, I do not care any longer about the direction of my sensor while I walk the rows of the survey grid.
Now, to be precise, my own sensors are built around plastic lab sample bottles of about 125ml (useful winding area = 75x50mm). The coils are made of around ten layers of 1mm wire and the polarization current is around 1.2Amps. We are using Isopropyl alcohol which is the one giving the best results (i.e. the highest signal with the shortest polarization duration) in our experiments.
The two coils can be fixed side-by-side for the noise cancellation but it is also possible to choose a common axial configuration which is more favourable to be mounted inside a fish for underwater surveys.
See the attached pix.

I hope these few comments will help you.
Willy

[rgecy]

I think we are all interested. Looks like you have done some good work.

So how much for us to get our hands on the kit?

Robert

[Geo]

If the price is normal and the circuit is not very... very complex then i am interesting to construct one
Regards

[Gene-Yo]

Mag

Definitely interested. I would like a kit that's either easy or almost built or finished. Willing to pay extra for this. So how much for this kit or finished product?

[rgecy]

So you peaked our interest and even emailed us, but you have yet to tell us what you are offering or HOW MUCH it will be!

SO WHATS THE DEAL?

[Willy Bayot]

I told you that I would come back with an offer in a few weeks. I meant it.
We have still to gather lots of data, decide about the final packaging options and get quotes from our PCB manufacturer before we are able to fix any final price.
We do not want to hurry-up our decision making. After working hard on this project for years, a few weeks more are peanuts.
I shall make a detailed report on our project status and send it to all of you.

Patience!

Willy

[pbowen]

Please let me know as well.

Thanks

[Gene-Yo]

Mag Kit

I have been in contact with Willy regarding this kit. Right now there are only 2 or 3 people that are ready to buy the kit. He needs 10 people so if anyone else is 'in' please let Willy know.

In case you didn't get his previous email the kit is around $650 USD (I might be off by a $20) but that's the range. You will need to make a couple of the items such a box, power source and detector wrapped with coil yourself. Willy informed me earlier this is very easy to do.

The resolution is around 1 gamma with a read every second. Typically a proton mag with this read rate will easily cost $3,000+.

[Geo]

Hi Gene.
Maybe Mr Willy to sell it a little more expensive (for example 10%) so the factory to be able to construct only 3...4 units
Regards

[Willy Bayot]

We could be able to take the decision to go on if we get at least 4 or 5 ordered units. This would cover enough of our production costs for a start.
Actually, we only have 2 up to now. This is really not enough to justify a production of 10. Producing less units would not improve the case as the one-time costs are still there even for a single unit.

Thanks,