Is It Possible To Diy A Bigger Coil For An Existing Pi Detector Model

[alan46]

Hi, I think of buying the Quest Scuba Tector Pro (https://www.amazon.com/Quest-Scuba-Tector-Metal-Detector/dp/B08HQYH81T), it is a Pulse Induction detector, i intend to use it on land so i need more depth hence i want to build a 15 inch coil for it, by measuring the inductance of the stock coil and building a 'similar inductance' big coil, will it work?

also, does the pulse power also affects the depth, i guess from the small battery and the advertised 14 hour life that it is using less power per pulse, if power maters then will using a 20% lower resistance for the new large coil (thinner wire) help force a bigger current and consequently more power (assuming it is driven by a voltage generator)?

 

note: I know i can find many similar models with big coils but for some reasons am limited to this particular detector and I want it to find gold jars 3 foots in mineralized ground

[Steve Herschbach]

You can build a larger coil for it, and it will work, but actual battery power matters a lot in a PI, and I would not expect to get much more depth. Certainly not gold jars at 3 feet in mineralized ground. That challenges much more expensive detectors, and if a really cheap detector could do it everyone would have one.

A better place for you to ask and get accurate answers is at https://www.geotech1.com/forums/. All those guys do is design and build detectors.

[Luis]

here is a man who makes them for the Nokta pulsedive.   he explains how to do it and if there is any piece that you cannot do yourself he has his page to buy it.  you can also buy the coil already made.the video is in spanish.                                       

 

 

[bklein]

What is he coating the coils with before they go into the oven and why doesn’t it stick to the wood?  Where does he get the coil forms? Is there a trick to get an English translation?

[Luis]

                     In this video all the steps to make a coil.  It is only in Spanish.  but you see all the steps

 

 

[Geotech]

31 minutes ago, bklein said:

What is he coating the coils with before they go into the oven and why doesn’t it stick to the wood?  Where does he get the coil forms? Is there a trick to get an English translation?

Probably he's using bondable magnet wire which just requires alcohol to activate. Then you want to bake it at ~150°F for maybe an hour to outgas the alcohol. I rub Johnson wax on my coil forms to keep the coils from sticking.

[Geotech]

5 hours ago, alan46 said:

also, does the pulse power also affects the depth, i guess from the small battery and the advertised 14 hour life that it is using less power per pulse, if power maters then will using a 20% lower resistance for the new large coil (thinner wire) help force a bigger current and consequently more power (assuming it is driven by a voltage generator)?

No, lower coil resistance won't help (and that would require thicker wire, not thinner). PI pinpointers are not designed to go deep and are more concerned with battery life so the pulse timing would likely need to be changed, as would the power supply that drives the coil. And because raw depth is not critical the RX circuitry is probably pretty skimpy and would need redesigning. In short, you need a different PI circuit.

Quote

note: I know i can find many similar models with big coils but for some reasons am limited to this particular detector and I want it to find gold jars 3 foots in mineralized ground

This circuit isn't going to do that.

[mcjtom]

14 hours ago, alan46 said:

Hi, I think of buying the Quest Scuba Tector Pro

A bit off topic of building coils, but I was thinking of buying this detector vs. Nokta Pulsedive for snorkeling and light diving.  Have anybody tried both and could offer some comments on what to expect and which one would be a better idea?