gpx5000 coil

[Bhathu saaii]

Hello guys. I wanna ask if i will make a DD coil for gpx 5000 with the diameter of 18",what number(awg) of wire should i use and how many turns should it be? Thank you people

[Tibuck19]

Hello guys. I wanna ask if i will make a DD coil for gpx 5000 with the diameter of 18",what number(awg) of wire should i use and how many turns should it be? Thank you people

Would you really trust a homemade coil on a 7000$ machine ? I know I wouldn't.

[Bhathu saaii]

Would you really trust a homemade coil on a 7000$ machine ? I know I wouldn't.

If someone has a knowledge or an experience how to deal with the modification,it's a great help. I was using concentric coil and the depth was not that good. Do you have any idea how to deal with this gpx5000?

[MartyJ1963]

@jINBIAO,,,Hope this helps. https://www.youtube.com/watch?v=vFeGlrq5h7w

[Bhathu saaii]

@jINBIAO,,,Hope this helps. https://www.youtube.com/watch?v=vFeGlrq5h7w

Thanks a lot brother. But, do you have an idea how to make a DD coil with 18inches diameter? Pr just even 15inches. Thanks a lot brother

[waltr]

There is a lot of info here and on the web on building DD coils. BUT nothing explicitly for the GPX.
Search and study coil building info for the TGSL and other VLF detectors. The principles would be the same.

[Hyena]

Thanks a lot brother. But, do you have an idea how to make a DD coil with 18inches diameter? Pr just even 15inches. Thanks a lot brother

Try to make 11", then 13" and then bigger. You will see, how complicated things can get For sizes 13" and bigger, start with cover and then wind coils. I tried it oposit way (as always) and shrinkage of cover after cooling is so big, I was nearly unable to get coils in and null... Then try to make 18". And let us know about your progress. Fingers crossed!

Would you really trust a homemade coil on a 7000$ machine ? I know I wouldn't.

Can you please explain affect of price of detedctor to coil construction?

[Bhathu saaii]

There is a lot of info here and on the web on building DD coils. BUT nothing explicitly for the GPX.
Search and study coil building info for the TGSL and other VLF detectors. The principles would be the same.

indeed. its quiet difficult to build a DD coil for gpx. yes. i agree. i am studying right now but kinda complicated if you dont have an oscilloscope like me. just looking for a scope for an accurate measurement. thanks a lot for that advice

[Bhathu saaii]

Try to make 11", then 13" and then bigger. You will see, how complicated things can get For sizes 13" and bigger, start with cover and then wind coils. I tried it oposit way (as always) and shrinkage of cover after cooling is so big, I was nearly unable to get coils in and null... Then try to make 18". And let us know about your progress. Fingers crossed!



Can you please explain affect of price of detedctor to coil construction?

thanks a lot for that advice bro..i am planning to do that tommorow..anyway,do you have some ways how to create it with details or specification in doing an 11inch DD coil? thank you

[Hyena]

thanks a lot for that advice bro..i am planning to do that tommorow..anyway,do you have some ways how to create it with details or specification in doing an 11inch DD coil? thank you

I just follow inductance (number of turns), resistance (wire thickness) and nulling (overlap) for given frequency. But I built this only for IGSL, IDX and similar simple VLF projects on geotech. If GPZ is Pi+VLF hybrid, you will need to control also parasitic capacitance of coils, dumping resistors...

Instructions for VLF coil building is on geotech, just wlak through "Coils" forum.

[Bhathu saaii]

I just follow inductance (number of turns), resistance (wire thickness) and nulling (overlap) for given frequency. But I built this only for IGSL, IDX and similar simple VLF projects on geotech. If GPZ is Pi+VLF hybrid, you will need to control also parasitic capacitance of coils, dumping resistors...

Instructions for VLF coil building is on geotech, just wlak through "Coils" forum.

Thanks a lot..ill check in coil how to do a VLF coil..how about the resonance frequency? Does it matter also? I think minelab gpx5000 are working on 18.75khz for the tx

[h9361]

Recently, I made a DD detector for the GPX5000.
TX: 300UH
RX: 450UH
It is normal to exclude iron now. But no mono coil is stable, I want to know if the pulse detector's DD probe needs to be adjusted to zero. Thank you!

Hello
Dear Refref
Can you tell me value of your RX damping resistor (450uH)?
Thanks