ML patent Application

[Altra]

Minelab applies for solder joint with ferrite bead shield patent. Also reiterates the benefits of Litz wire coils. Good reading for coil experimenters, weather you agree or not with the system.

Probably better as a trade secret than a patent.

[hdphilip]

They beat me to it,

i always put ferriite beads around my solder joints, matter of fact theirs another place ML can use them too!

Philip

[ApBerg]

Ferrit beads ....I use them for fine tunning (nulling) in DD coils ....(and little pieces alu foil for faze shift).. so thake care where you fix those beads, they can offset nulling.

Best regards.

Ap

[bklein]

Is this saying that there is a discontinuity created when litz wire ends are joined and then connected to the coil coax and the ferrite somehow eliminates it? If true, I think they should describe in more detail how it does.

Is it something like: the joint creates a detectable discontinuity and the ferrite - chosen and placed just right - counteracts this discontinuity?

0062 is suggesting they will have accellerometer sensors and perhaps flux sensors in the coil housing.

[Aziz]

*LOL*
That's pure waste of company money.
You as the customer have to pay for this.

The invention isn't worth the money!
Fuuuuuuugggg, they should save and invest the money to legally sue me!

Aziz

[bklein]

Aziz,
Look at my post above yours. If it does what I am asking if it does it is big.

[Davor]

No. Ferrite magnetically shields the solder droplet from creating eddy currents, which is a non-issue in case you are not criminally messy in your welding. Perhaps it is a way of hiding the balancing means with the unsuspecting beads, rendering the off-balance coils unrepairable to the uninitiated ones, hence the techno babble gobbledegook in the patent. Smokescreen and mirrors.

[bklein]

Doing some quick Googling, I buy the eddy current generation at the joint. This is well documented and the currents involved in TX mode make it a real likelyhood. They have eddy current soldering equipment that does this on a local scale. I am intrigued to learn more about just what the ferrite does. Does it just reduce the imposed signal on the shield or does it also improve the TDR reflection?

[Carl-NC]

"which is a non-issue in case you are not criminally messy in your welding."

That's a good way of putting it.

[authere]

Hi All,

I'm having personal issues with my computer,I seem to be able to push the right buttons now, 5th time rucky....Ok!!, right!!,...I seem to recall "Woody" saying that he uses leadless solder to join the coax to the coil wires, I have been doing this but i don't recall the reason why....anyone!!!!?

Ron

[dougAEGPF]

No. Ferrite magnetically shields the solder droplet from creating eddy currents, which is a non-issue in case you are not criminally messy in your welding. Perhaps it is a way of hiding the balancing means with the unsuspecting beads, rendering the off-balance coils unrepairable to the uninitiated ones, hence the techno babble gobbledegook in the patent. Smokescreen and mirrors.

Non ML coil manufactures will not be able to use this method (patent infringement!) with their coils and perhaps future ML detectors will only be optimized for,or only work with ML coils?
dougAEGPF

[dougAEGPF]

Another ML patent.Will be very interesting to see what its about!
http://pericles.ipaustralia.gov.au/o...nNo=2013201330
dougAEGPF

[hdphilip]

yes it wiil be, I'm always looking for new ideas.....

[Mechanic]

The way to avoid the problem in the first place is to have a litz coax cable with the same amount of strands as the coil wire and solder and insulate each of the strands individually.

Cheers Mick

[bklein]

Wow. I was trying to do more Google research on eddy currents in solder joints and eventually came up with this search string:
"pdf Performance Optimization of Local Magnetic Resonance Surface Coils and Antennas"
It comes up with a bunch of PDF reports on designs of coils and electronics for MRI systems. Some of it really interesting with cool technology. They don't seem too concerned about solder joints though.... :-)