Mini Pulse finally packaged up!

[godigit1]

So here it is, Im calling it the Mini pulse "Magnatrol" wader.





Its mounted on PVC shaft with the battery pack built into the shaft.
I'm using a Whites Arm cuff and a clamp on bicycle grip for the handle.
Garrett AT water prof headphones and a TDI Dual Field coil.
The controls are magnetic, I put roller bearings on the pot's and I just keep a rare earth magnet on my scoop to adjust them.



Here is the small Jewelry coil I built for it but still have some packaging to do to it.
I used a needlepoint frame for the pattern and laminated a skin on for the case that will eventually be gel-coated.

4" 3/4"x 9" Oval Basket coil!
26 awg solid tin plated copper wire.
320Uh and 3.1 ohms resistance.



Here are some scope shots!
.

I've had it out for one quick test where I made a little video and two 4 plus hour hunts so far and I have to say I,m very pleased with the depth and sensitivity using the TDI coil. I kinda don't want to take it off.
So far Im hitting nickels decently at 12 inches and hitting items small enough their hard to find with my TDX pointer.

Here is the video I did its not to good I was holding my headphones to the camera and that didn't go to well, so when I actually could hear it it hit the nickel very well you just cant see the sweep. But Here it is anyway!

https://www.youtube.com/watch?v=tEb7qhybrXw

Thanks to everyone at the forum for covering things so thoroughly I hardly have to ask a question and especially to George and Carl for their great projects and devotion to the forum.

Best Regards.
Digit

[Chet]

Hi Digit
Great work! And great performance.
Chet

[6666]

4" 3/4"x 9" Oval Basket coil!

Be interested to see the result

[6666]

How did you make the coil housing and how did you bend the wood ? thanks
Your idea looks way better than my idea with a router .

[Qiaozhi]

So here it is, Im calling it the Mini pulse "Magnatrol" wader.

I have added you to the Hall of Fame -> Completed Minipulse Plus Projects by Geotech members

[6666]

Godigit1 I see you used a needlepoint frame for the coil housing good idea.

[godigit1]

Godigit1 I see you used a needlepoint frame for the coil housing good idea.

Hi 6666,
I laminated a thin ply to needle point patterns, but the needle point patterns only provide for about 3/4 inch of inner thickness. They would work with the thicker wires like Litz if a spacer was added.
The other drawback is you have to design the coil to their size. I find allot of them at second hand stores but the ovals are a little harder to find.
This particular coil was designed around that pattern, It performs pretty good on the bench, I haven't had it over actual ground yet but it hits my 1.2 gram test nugget at close to 5 inches .
I'm still trying to wrap my head around all the dynamics of coil building so I'm sure its not perfect.
digit

[godigit1]

Hi Qiaozhi,
Thanks again for the great project and for adding my Mini Pulse to the finished projects page.

[godigit1]

Hi Chet,
Thanks for all the help along the way. Your posts were very helpful to me. We are lucky to have such a wealth of knowledge shared on this forum.
Be well
digit

[jimfrombr]

Hi Digit, I just completed my MMD and it is working fine but I wanted to try using a TDI coil that I have. How did you determine the damping resistance? I am somewhat of a beginner with the o scope and have only made a couple of kits and coils. Any advice would be appreciated.


regards Jim

[godigit1]

Hi jimfrombr,
For the damping resistor on my mpp with a 12 dual field I am using a value of 660 ohms. I have two 2 watt resistors in series a 270 and 390.
I kept blowing my damping tool set up so for this value I swapped resistors around tell it looked close on the scope.
Im a beginner in electronics as well so on all my Md builds I have added d-sub connectors to easily swap resistors out for different coils.

There are 4 wires inside the dual field cable I have a red a clear jaketed and two non jacketed wires. I tied the two non jacketed wires togeter and they are hitched to RX ground. the red wire is connected to Tx ground and the clear wire is connected to TX and jumpered to RX.
This should get you really close. I think both Tepco and Kt315 have posted animations of proper damping but I cannot remember the threads at the moment.

Hope this helps.
digit

[Teleno]

What's the commercial concentric coil you're using and how do you connect it? Is it a balanced coil?

[godigit1]

Hi Teleno,
Im using a 12 TDI dual field coil it is a mono of coarse.
We must have been posting at the same time but is is connected as above.
I have two more minipulses on the bench and may try your mods.
Thanks for all your work.
digit

[jimfrombr]

Thanks Teleno and digit. That should get be going in the right direction.

cheers!