XP deus coil modification

[6666]

Wow Henrik 5 Bronze age finds and gold, super cool finds.

[golfnut]

Hi thanks, gold is the only metal I have not found. I will have to get out there and do some more !!

[Henrikras]

I was thinking to make a resume, like a happy ending to this thread.
A Big Thanks to all the great help you gave to this project.

Step 1. A working Deus coil must Be taken apart. At the electronic side you must lift of the lid at the top, its sealed with silicone and gentle losen the PBC board. Take some pictures before you disconnect the wires and make your own schematic. The thinny ones is the RX. If you want to scope something, ist a good time now. Picture 1.
Be carefull with the wires coming out from the coil, you need to measure the RX and the TX in your Deus Stock coil.
I was using a Bigfoot coil and that was measured : RX 15.9 mH - 70 ohm and the TX 10.4 mH - 20.4 ohm.
It is a good idea to find the resonans at the Stock coil. I was using a 15 nf and that gave RX=10.4 khz and TX=12.65khz
but If you are using a 9" coil it would be another resonans. The enductance is different 9" - 11" - 11"/13" coils.

Step 2. Find a little plastic box you can install the PBC board and a Battery and two plugs. You need only a 4 pin plug and mine choice was the standard microfone plug like them used at many detectors. Plug no. 2 is the charging plug.
I found a mini USB chassic type, that gave the benefit that the Stock charger can Be used to charge the Battery.
Battery either the Stock Battery or like I did or a stronger cell. Picture 2.

Step 3. Cable at the Stock coil ! I had to take the Stock coil and put a cable with a plug at it, to see my project would work. Doing that you still got a working Stock coil, now just with a cable to the electronic. My cable is 40 cm long, just enough so the box can come up to the top at the lower stem... I found out that there must Be some distance between the control unit and the new little plastic box with the PBC board. (Overloading the signal I think). Picture 3 and 4.

Step 4. Now you are ready to make what ever coil you would like... I was first going after a 6" coil, but couldn't easy find a good Shell to work with. A helping hand gave me the information about DB Shells (Donald Bowers) and he was nice to help me with his 7" Shells. This was a Very good choice. Picture 5.
Ps. The cable I used - picture 6. But I think that you can use S-VHS cable. (Look in the Thread information is to be found).

To be continue - with the coil and shielding.

Henrik.

[Henrikras]

Coil and shielding.
Step 5. Now you must wind your RX and TX. By great help from the Coil Calculator, you can find the perfect wires to use. http://www.geotech1.com/forums/showt...oil-Calculator It is important that your close to the Stock coil resistance allso..(20 and 70 ohm).
At mine 7" coil had the RX/TX a innerdiameter at 40.5 cm, but you need to add some turns % to hit your Inductance and that took some time to find out. I ended with 234 turns with AWG 0.18 wire at the RX and 198-200 turns with 0.315 wire at the TX.
It is important that your Winding is done tight.. I was doing it by hand and was using the lack spray kontact 70 every 20 turns, and quickly after the Winding was finish, before the lack dryed up, I was tighting with some thin thread.
Its a good idea to tight your coil every 1 cm with the thread, to make Your work Very stable.
Skippy told me how I could take out the last 4 windings by par, to help in the end to find the Inductance . Like 196+2+2 turns. I didn't found out how, but you can find this idea in the Thread. Its no so difficult to take off one or two turns If you end to high, I had to do that, because I found out that the TX was sensitive to get this project to work. 10.45 was to high, the low ID didn't work, but after I came down to 10.35 mH I hit the nail. At the same time I was working with the resonans, and found that even more sensitive. By that I learned, that the Inductance is more a guiden, but the resonans is what we need to hit, and the TX is changing much in performance, the RX not so much.
After I had made the RX and the TX coils, I had to shape the corners a little.. That lowered the Inductance a little and Helped me, because I was a little to high.
Now you are ready to connect and turn on and do some scope. You need to find the Null and see that you got some space in the Shell to work with. It a good idea to get some 2-5 mm air from your coils to the Shell.
If your signal is like a dobble bump, try to swob the RX or the TX wires 180 degrees.
You must do some test with different objects and conductivity, Iron, foil, coke, Gold, low and high condutive coins, to see that all your IDs is the same like your Stock coil.
If and when you came to this point, your are ready to work with the shielding and closing up.
The shielding was a nightmare to me... Inside shielding at the Shell, small wires from the inner to the outside, drainwires and shielding outside allso. All this made with Very much graphite 33 spray down to 300-500 ohm.
I did like XP did, connect the drainwire to the RX cold side, and to me that was the RX wire from the start of the winding, the inner wirer. That worked.
Step A was to paint the graphite inside the Shell, Remember small wires to the outer and the drain wires.
I made the drain wires like a S, Remember allso the drain wire you shall use to close up your shielding, to the lay after you had fill up the first amount of the Compound mass.
Pictures helping to understand the work.
To be continued.

[Henrikras]

Continue.
After I had filled up the Compound mass like 70-80%, the searchcoil was ready to go out and do some test....
I didn't work perfect at that time, I needed to finish the Sheilding at the bottom. That did the last to get nice sharpe signals.
Shielding ready, then the coils down to the shell, test it and do the finetune Nulling and fill in the Compound mass. Its a good idea to use a plastic bottle turned up side down, so the small air bobbels stays in the bottle. Wait 20-30 min. after you had mixed the mass.
Waiting time is 18-24 hours...
The rest is up to you, like paint and finish.

The end....
I hope that all this information can be usefull, and I know that it is written like from a newbie to a newbie, but it was my first succesfull project, and I'm in a learning phase. There could be some work I did and you would do different, I know that..
Here is some link that could be usefull..
http://www.circuitspecialists.eu/bla...ating-compound
http://m.youtube.com/playlist?featur...5rzuhKKOIoCBxg
http://m.youtube.com/channel/UC6NSTpUGbtDuP092H0NTKhQ
http://www.wires.co.uk/cgi-bin/ss000...ION&PR=-1&TB=A
http://www.siversima.com/rf-calculat...FfB3cAodsAgAzg
http://www.geotech1.com/forums/attac...3&d=1332544265

If could had lost something, then you are free to ask...

Henrik.

[golfnut]

Hi this sounds a little odd...

"RX 15.9 mH - 20.4 ohm and the TX 10.4 mH - 70.0 ohm"


If you consider the Rx wire is thin and the Tx wire is thick, I would expect the higher L Rx coil - using thin wire to have the greatest R value too !

Steve

[Henrikras]

Can't edit now.. To late.

SORRY - made a mistake in the begining. Gulfnut notice that - RX 15.9 mH and 70 ohm. TX 10.4 mH and 20 ohm.

[golfnut]

Approx graphic of construction..

[sinclairuser]

ask qiaozhi, or carl, tell them exactly what to edit and they will, some people follow these things blindly, might be better if its edited.

[Henrikras]

ask qiaozhi, or carl, tell them exactly what to edit and they will, some people follow these things blindly, might be better if its edited.

DEAR ADMIN... Please edit line 7 at no. 288.
This is the line; I was using a Bigfoot coil and that was measured : RX 15.9 mH - 20.4 ohm and the TX 10.4 mH - 70.0 ohm.
I would like it to Be; I was using a Bigfoot coil and that was measured : RX 15.9 mH - 70 ohm and the TX 10.4 mH - 20.4 ohm.
Thank you Very much.
Henrik

[Qiaozhi]

DEAR ADMIN... Please edit line 7 at no. 288.
This is the line; I was using a Bigfoot coil and that was measured : RX 15.9 mH - 20.4 ohm and the TX 10.4 mH - 70.0 ohm.
I would like it to Be; I was using a Bigfoot coil and that was measured : RX 15.9 mH - 70 ohm and the TX 10.4 mH - 20.4 ohm.
Thank you Very much.
Henrik

Post corrected as per your request.

[Skippy]

I was just thinking about the external graphite coating, and the method you used to make a connection to the internal shield / ground. Then I realised that XP don't have to intentionally make a connection - they use the two battery charging pins to directly connect the outer graphite to the circuit. And because of the series-connected diode used in the charging circuitry, there is no need to isolate one of the terminals, as no current can leak. I guess on charge a small current must flow through the graphite, but it's a trivial amount.

[Henrikras]

You are a genius - Skippy.. Perfect.

[Skippy]

Except for the fact that there needs to be a big unshielded region near the electronics circuit-board, so that the 2.4GHz antenna can work correctly...so maybe the charger contacts area is not coated. They could just paint the graphite around the edge of the hole where the electronics sits, so it links inner and outer surfaces.

[Henrikras]

There is no shielding at this parts of the Shell the electronic is placed, and I just measured 1-2kohm from the outside to the inside lay,
and the charging pins is removed... Sorry !so that theory couldn't be right.
Skippy could you send me a PM with your adress.. Then I could send you the XP coil I open up. Maybee you find out the secret.
Henrik.