I have a proposition. In need of Coil for Silverdog Surf PI.

[neptune769]

Hello Everyone,

Back in 2012 I ordered one of Silverdog's Surf PI kits. I assembled it, tested it and it all worked fine. I made a housing for the electronics to be waterproof for scuba diving. I tried making two different coils but had some very bad results. My father who know a 1000 times more about electronic tested it with a scope. At first one of the ICs were bad. That was fixed. But we still couldn't get it to work with a coil. It wouldn't detect anything. Coils are not my thing. So I packed it up and set it aside until now. I was thinking, Is there anyone here that would be interested in a trade? I have a 3D printer. I would be willing to design & print one or two coil covers for a known working 8" to 10" (200mmm - 250mm) coil. I can print up to 280mm. If you are interested in working something out let me know. I live in the US.

Thanks,
Dennis L.

[surfdetector]

Hi Dennis,
I am curious, was it just a mono coil that you wound for it?
Cheers

[neptune769]

Yes. In fact it was what is in the instructions for the original Hammerhead. It was tried with shielded Aluminum tape as well as not with no tape.

[6666]

Yes. In fact it was what is in the instructions for the original Hammerhead. It was tried with shielded Aluminum tape as well as not with no tape.

Did you build the 10 inch 26 turns of .4mm coil

[neptune769]

It was a long time ago but I'm pretty sure that is correct.

[6666]

Ok lets go, firstly lets assume that your machine is actually functioning correctly, in the HH document it says make a 10 inch coil with 26 turns of .4mm wire, my HH coil measures 510uH on my super dooper inductance meter, the original surf coil was around 230uH and 1.37 ohm's, the surf kit came with a 390 ohm damping resistor to match the 230uH coil like the original, now it could be that if you are using the 390 ohm R for damping a 510uH coil, it may be severely over damping the coil and killing the sensitivity, you could try and make a surf coil, the reported specs are #1 20 turns 23cm .5mm and #2 22 turns 20 cm .5mm,

[kt315]

new matter for you. 'basket fastest coil'. you need to learn.
second matter. 'Eric Foster's WOW! 5us'.

[neptune769]

Ok lets go, firstly lets assume that your machine is actually functioning correctly, in the HH document it says make a 10 inch coil with 26 turns of .4mm wire, my HH coil measures 510uH on my super dooper inductance meter, the original surf coil was around 230uH and 1.37 ohm's, the surf kit came with a 390 ohm damping resistor to match the 230uH coil like the original, now it could be that if you are using the 390 ohm R for damping a 510uH coil, it may be severely over damping the coil and killing the sensitivity, you could try and make a surf coil, the reported specs are #1 20 turns 23cm .5mm and #2 22 turns 20 cm .5mm,

Thank you for the info. I will have to pull the project back out and start playing again.

[neptune769]

new matter for you. 'basket fastest coil'. you need to learn.
second matter. 'Eric Foster's WOW! 5us'.

Thank you for the info. However I'm not ready to get into that just yet. I have heard about that though. I may possibly be getting a Minelab Excalibur II from a friend. From my understanding it has a problem with fine gold chains and small gold targets. Maybe I can make my Surf PI get the small stuff.