How to approach making a coil for Infinium

[echo]

Infinium Mono Coils

Hi All,

I've heard that you can damage the Infinium front end by trying to connect a Minelab coil and this is probably why the rumours surfaced; because people had tried that and I have no reason to doubt that it's true.

Trouble is - a little knowledge can be dangerous and you can't just blindly connect a coil to a different detector and hope that,

1. The pinouts will be the same,
2. The impedance will be appropriate
3. That the inductance will be identical
4. That there isn't a DC path back from the induction coil into the RX circuit
5. That the mutual coupling won't be excessive,
6. The secondary back emf won't exceed the breakdown voltage of the RX front end
7. That there isn't a dampening or snub component required
etc.
etc.,

I'm quite happy to test my electronics skills and use my detector as a guinea pig but I need some basic information first so that I can understand what I'm dealing with.

I'm sure that some headway can be made if we can examine a faulty coil to determine what electrical parameters we need to adhere to and then we can work out what margin for error we have to play with.

Personally, I've never blown up anything through poor design, but I certainly have through rushing.

[Pinpoint]

wrong! apparently there was? or still?Westcoil in western australia in collaberation with Australian goldminingcentre for Garretts,for infinium making PI coils for the infinium in larger sizes.or configurations?
This may still be ongoing or else closed due to lack of interest or some bueracratic concern??google this up?google is still u friend?
cheers! Rov.

They've stopped making coils due to lack of interest and $. They made three types of coils that were the same shape and same size, a 10" oblong shape. Two were mono's and one was a DD. Just what the Infinium needed to add to their variety

Apparently, the maker of these coils won't disclose on how to make them nor will he make any coils.

http://www.goldminingcentre.com.au/Gold%20Detector/New_Folder/accessories%20garrett%20infinium.shtml

[Rov]

wrong! apparently there was? or still?Westcoil in western australia in collaberation with Australian goldminingcentre for Garretts,for infinium making PI coils for the infinium in larger sizes.or configurations?
This may still be ongoing or else closed due to lack of interest or some bueracratic concern??google this up?google is still u friend?
cheers! Rov.

[Pinpoint]

Apparently, you need to be EXTREMELY precise and the slightest miss-calculation will damage your Infinium beyond repair.????

[gedfire]

Mono Coils

I will try to see if can get one or locate any schematics.I think I will work on building one myself.Will keep everyone informed.

[echo]

Anyone have a non-working mono coil?

Hi All,

Does anyone have a non-working mono coil that they'd be prepared to disassemble or sell for research?

I'm still keen on building a large mono coil but I need to work out the configuration of an existing coil so as not to damage the Infinium with experimental coils.

I've seen on posts that people claim to have a copy of the circuit but no-one has been able to post or email one yet. If you do have one, I'd be grateful for a copy.

Thanks.

[gedfire]

Infinium Coil

Again, the blown box may have been the result of incorrect calculations.The laws of electricity follow certain rules.They should have worked out the amps and connections to the infinium.In fact now the infinium is blown,it would be a good opportunity to take it apart,work out its basic schematics.Maybe do the same with the coil, then do a little reverse enginneering.I guess the researcher would want to have a multimeter with them and good experience with electronics.The bottom line is these devices are man made and I certainly think a good electronics enginneer (with maybe a lot of time) could figure it out.Their is hope however, still, I am saving to get the TDI.

[adrian ss]

So far the few people I have heard of who have attempted to build and fit their own coil to the Infinium has resulted in a blown control box cct

[gedfire]

Infinium Coil

I understand and oh yes I will get a TDI eventually as I have whites pi pro dual field and the MXT.I will also be getting the GMT too.

When I get the TDI I want to waterproof it.Really good too as I have lots of stuff to do with it in the water....

Yet I still have the infinium and would like to explore its full potential.I made a post about an inline circuit that allows me to use bigger coils from minelab or coiltek on my infinium.I just need to know if it is technically possible to create such a device? Maybe it could be powered by the detector or have its own batteries.I know it should work but all that amps,gain, resistance voltage pulse rate is not really gelling.

Any suggestions,leads?

[adrian ss]

I haven't given up hope yet.

[Infamy]

Your flogging a dead horse get a TDI. Been there sold the bloody thing. The Garret ownership are too long in the tooth, they need an over haul in their hobby section. Their hobby detectors have gone down hill compared to the competition which is reflected in the lack of support for the Infinium, they never really understood what they had, if they had they would have made larger coils for it.

[gedfire]

Larger coil for the infinium

I own an infinium and would like to have one of those 18 inch coils.If anyone makes one that works and would like to make an extra one for a few benjamins I would appreciate that.

Better yet,it would awesome to have one looking like the coiltek 12 by 24 incher.

Garrett seem to be slow on certain aspects of metal detector developments.Kinda like the groundhog battery design.I am not expecting coils like those from them at this point in time.

[adrian ss]

Here is how my multimeter sees the 10 x 14 inch infinium mono Coil.

I would not have a clue if this is correct or not, but most probably not.

http://i792.photobucket.com/albums/yy203/ausnapshot/DSCF2160.jpg

[adrian ss]

18 Incher

G/Day Chaps,
I have been reading what everyone has to say re an 18 inch mono for the Infinium, so I thought I would register and put in my two bobs worth.

You cannot take any notice of the resistance and Inductance readings across the Inf coil Plug pins because there is a couple of polarity sensitive components inside the housing that screw the readings up a tad.
My 10 x 14 mono gives 67.4 ohms/77 micro h and 0.9 ohms/186 micro h.

the 8 inch mono gives similar but slightly different readings.

The polarity sensitive readings give around the 430 k ohm mark in one direction and infinity in the oposite direction. Take the readings across the two male pins and the two female pins.

I have not seen a schematic of the coils and plugs but the readings suggest that there are at least two diodes in there. If there are any damping resistors involved I would think that they would be in the control box. As I said, I donot know the cct setup of these coils so I would appreciate any info you blokes can come up with.

If someone has a cct diagram of the mono coils I would realy like to see it if possible.
Cheers,
Adrian SS

[echo]

Infinium Mono Coil Design

Hi All,

I've been monitoring the forums and it seems that there's not a lot of progress being made on the homebrew Infinium Mono coil front.

I've been looking to find a source for the proprietary coil and headphone connectors as well, but it's looking pretty obvious to me that they are specially made for Garrett.

I've checked out most of the larger connector manufacturers as well as some specialist ones that do mil spec connectors but there's not much out there that even comes close.

I did come across a very similar unit made by an obscure company in China, but this had two male pins on the plug as opposed to one male and on female. In other respects, it looked almost identical. I may have to follow them up with a direct approach.

I only have a standard 10x14 double DD coil at my disposal, so I can't measure the inductance or resistance of the stock 10x14 mono to get a baseline to work with.

I note that Wirechief has measured the resistance to be 77.8 ohms, but to me this seems somewhat high for a PI transmit coil series resistance. The inductance is in the ballpark, so I'd be very interested in any other info that people have collected on the coil design that may give me an idea as to why the R is high.

I'd be interested in whether anyone has seen the inside of one of these coils and knows whether they've used enameled wire, multicore, or Litz etc.

Any schematics would also be greatly appreciated.

Hopefully with a bit of collaboration, we may be able to come up with a design for a larger mono coil.