best pulse

[Rafael]

Greetings. I have a Felizjoo. You can adjust frequency, pulse width, delay, speed, etc... It has Automatic and Manual Ground Balance. If you want to use it to search for gold nuggets in highly mineralized soils you should do your own tests with various types of coils.

I recommend you can make a double Monoloop coil, a small DD coil and a Super DD.

If you want to play it safe, the GD4 detector, even the Hammer would be very good options but coil design is critical in these red soils with very high iron content.

Also your motherboard case should be wrapped in a faraday cage to eliminate as much noise and interference.

Excuse my poor english

[ZOUjiarui]

The felezjoo pi has no ground balance function, it is ground adjustment not ground balance. As far as I know, the forum has ground balanced pi only gs4, HH2 may be successfully produced. Coils are probably not that important, since heavily mineralized ground requires the sensitivity of the machine to be turned down so low that small objects like coins are almost undetectable, larger coils may be more useful

[GeoMax]

ZOUjiarui,

maybe a detector solution to your red clay background noise problem (ground balance) is already in front of you, but you haven’t seen it yet because of its simplicity. Have you tried the Russian pirate pi circuit? There are at least 10 variations out there in the Internet and every version does the simple job. This detector is a super simple pi detector made of a handful of components. The front-end circuit is like a pi detector, but after the front-end amplifier comes the difference. The target signal passes a filter and then the output switches the audio signal. Super simple circuit, no complex signal timing required. Additional to the front-end circuit you need to add a poti to reject the ground noise level at the front-end OpAmp. Just google for "Russian Pirate detector" circuit. A ready assembled detector kit you can buy at about USD 30,- plus shipping on eBay already.
Here the link... https://www.ebay.com/itm/185699560411?

GeoMax

[ZOUjiarui]

ZOUjiarui,

maybe a detector solution to your red clay background noise problem (ground balance) is already in front of you, but you haven’t seen it yet because of its simplicity. Have you tried the Russian pirate pi circuit? There are at least 10 variations out there in the Internet and every version does the simple job. This detector is a super simple pi detector made of a handful of components. The front-end circuit is like a pi detector, but after the front-end amplifier comes the difference. The target signal passes a filter and then the output switches the audio signal. Super simple circuit, no complex signal timing required. Additional to the front-end circuit you need to add a poti to reject the ground noise level at the front-end OpAmp. Just google for "Russian Pirate detector" circuit. A ready assembled detector kit you can buy at about USD 30,- plus shipping on eBay already.
Here the link... https://www.ebay.com/itm/185699560411?

GeoMax

Pirates are useless, he barely detects coins. Very little depth on the soil, he is my first detector

[ZOUjiarui]

https://youtu.be/mmaT1zLIL5w
Not just red soil