Slightly perplex as to what a PI detector is for.

[Infamy]

Just going through the site doing background reground reading when I came across this comment.

https://www.geotech1.com/forums/foru...a-large-object

Carl-NC "PI detectors are mostly designed for the beach or gold fields and are optimized for small low and medium conductive targets. They are less sensitive to high conductors. VLF tend to be most sensitive to high conductors."

So does this mean that a PI detector like the Crossbow Classic is optimized for high conductors?

[Qiaozhi]

People who use pulse induction detectors are generally looking for low conductivity targets such as gold nuggets. However, a PI can be optimized for high conductivity targets, if that's what you want, but then low conductivity targets will be compromised. The Crossbow Classic is optimized for use on the beach.

[pechkata]

„PI детекторите са проектирани предимно за плажове или златни находища и са оптимизирани за малки цели с ниска и средна проводимост.

[Infamy]

People who use pulse induction detectors are generally looking for low conductivity targets such as gold nuggets. However, a PI can be optimized for high conductivity targets, if that's what you want, but then low conductivity targets will be compromised. The Crossbow Classic is optimized for use on the beach.

Looks like your the person to put this scenario to.
I've built a semi autonomous boat (has gps autopilot) 1m long that tows a barge, that can carry large coils up to 1m diameter.
It tracks more accurately now then when I started out and reducing coil size is now possible to maintain reliable search overlaps.
So my intention is to search estuary mud for a multiple coin hoard likely silver only.

Now.
I have nearly all the components to build either MPP Beach or Crossbow Classic.
Which is more suited for optimizing for the situation described with search coils greather the 24 inch diameter?
Is optimizing just down to slower coil speed or is there more to it than that?

Summer holiday reading this year is 'Inside the metal detector' 3rd edition, more interesting than I expected, always wondered what happend to the Pulse Devil.
Met Dave Emery in 2003 wish I could remember every thing he said about this amazing detector he was working on. Going full circle I'm now starting to understand why I liked the CZ20 and the Sovereign and maybe a PI detector is the wrong road for my endeavor. This project has been on my books for 15 years aleast I really need to get on and finish it.

Thanks

[Qiaozhi]

Looks like your the person to put this scenario to.
I've built a semi autonomous boat (has gps autopilot) 1m long that tows a barge, that can carry large coils up to 1m diameter.
It tracks more accurately now then when I started out and reducing coil size is now possible to maintain reliable search overlaps.
So my intention is to search estuary mud for a multiple coin hoard likely silver only.

Now.
I have nearly all the components to build either MPP Beach or Crossbow Classic.
Which is more suited for optimizing for the situation described with search coils greather the 24 inch diameter?
Is optimizing just down to slower coil speed or is there more to it than that?

You might be better off looking at Delta Pulse. I don't have any experience with that PI detector, but I understand that it is optimized for large diameter coils.

The problem you will find with all these detectors will be the lack of iron rejection, so you'll be as likely to find an old rusty bicycle, or shopping trolley, as a hoard of coins.

[Infamy]

You might be better off looking at Delta Pulse. I don't have any experience with that PI detector, but I understand that it is optimized for large diameter coils.

The problem you will find with all these detectors will be the lack of iron rejection, so you'll be as likely to find an old rusty bicycle, or shopping trolley, as a hoard of coins.

I have a board for a Delta Pulse Legend +, maybe I need to have a look at that.
I aso have a functioning Vandal Pulse V2.1 with 1m diameter coil, perhaps that needs a reassement.
My solution to the iron problem is to survey for all targets then do several passes on target locations with sub 24 inch coil detector that has discrimination..
If I could build a 24 inch + Sovereign coil then I do only that, but I'm a better hunter than coil builder.
I'm not into swinging coils about these days, but sitting in a chair watching a model boat do a preprogram survey route I find appealing.

[Carl-NC]

Probably any of the detectors can be modified for the task. For a silver coin hoard I would set the TX pulse width out to 200-300us, then you need to slow the pulse rate down to manage heat. Sample delay is not very critical, 20-25us will do.

[Infamy]

Probably any of the detectors can be modified for the task. For a silver coin hoard I would set the TX pulse width out to 200-300us, then you need to slow the pulse rate down to manage heat. Sample delay is not very critical, 20-25us will do.

Thanks, noted and will be studied this summer.

[Infamy]

The problem you will find with all these detectors will be the lack of iron rejection, so you'll be as likely to find an old rusty bicycle, or shopping trolley, as a hoard of coins.

Places that are percieved too difficult to search have great potential but don't tell everybody