Whites Surf PI schematic

[daverave]

very sorry to hear about your father passing away....i know how your feeling as i lost my mother about 3 years ago and i still havent got over it and i guess that i never will...take care mate.

[sukri01]

sorry dave, i couldnt try it now, father just passed away, ill report back when ive settled things around, many thanks for your help.

[daverave]

was my info ok as no comment seen

[daverave]

I need some advice on my surf XX board.. Ive made an 11" coil with approximate inductance of 500uH, it had good depth but not stable at the beach, always causes false signal. i need to swing very very slow to avoid falses.. i'm using aluminium tape for shielding. if damping resistor is the problem, can anyone give tips for tuning the damping resistor correctly. ? thanks..

if you want to get the damping resistor correct then use a pot of around 1k 3 watt in place of your 390 ohm resistor and adjust until you get clean waveform without ringing then measure the resistance of adjusted 1k pot then replace with fixed resistor of the same value...the false signal could be caused by the detector responding to the wet sand....you may need to make the sample delay later so adjust the preset on the pcb....and make sure you fully screen the pcb with aluminium foil making sure the foil does not touch the pcb and connect the foil to ground via a wire to the ground connection on the pcb...use paper clip to connect wire to the foil.

[6666]

15V

Thanks Dave

[daverave]

Hi Dave
What voltage are you useing ?

15V

[6666]

sorry for the very late response cause i didnt receive a notification of reply via email....i did a few mods like increase the tx frequency to 1500hz and increased tx pulse so that detector draws about 120ma...my coil is 12" diameter and about 15 turns of 30 swg copper wire...and i got the external noise problem lower with shielding.

Hi Dave
What voltage are you useing ?

[Watanabe]

How may turns, Paku?

Nice project.
Congrats.

[paku]

http://www.youtube.com/watch?v=MqPl9d1CdzI

Thats Is My Surf PI

Coil Spec
Size Deameter : 22cm
Enamel copper wire : 0.5mm
Inductance Before binding : 0.354mH
Inductance After binding : 0.378mH
Resistance : 0.00

[daverave]

Hi Dave,

nickel half crown (1947-194 is about 32 mm ?
What is difference between surf pi and surf pi pro in depth for you ?
Can you please explain your modifications on surf pi.
How big is coil, how many turns and what type of wire is it ?

I was building bigger coil for more depth for my surf pi pro... coil about 32 cm...

sorry for the very late response cause i didnt receive a notification of reply via email....i did a few mods like increase the tx frequency to 1500hz and increased tx pulse so that detector draws about 120ma...my coil is 12" diameter and about 15 turns of 30 swg copper wire...and i got the external noise problem lower with shielding.

[paku]

Surfmaster is Good And Working PCB
make Small Change On Board I Get 1euro deep 60cm now < this is fake joke Thanks

[6666]

I already attached my cable to coil so no metal clamp is used anymore, adjusted offset to 0 volt, but still the same result. Adjusting delay makes some difference, but nothing better. Still beeping everytime i move my coil or my cable and dont get any depth. Tried outside, where are no metal objects, wires or something like that.
Now i am wondering if my coaxial cable can be the problem. I am using cable as in this picture. It has a layer like foil... What cables do you guys use? USB? [ATTACH=CONFIG]28525[/ATTACH]

This type of cable has solid wire core, be carefull it does not flex
or it will fracture.

[greylourie]

Muito bom ! Oh and you found some rings ! A good start to the year.

[6666]

Good project Watanabe

[Watanabe]

This is my surf-PI finalized!
Thanks everyone.

http://detecwata.blogspot.com.br/2014/01/surf-pi.html

http://detecwata.blogspot.com.br/2014/01/bobina-nova-para-o-surf-pi.html

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