How to improve my Surf PI 1.2 for a mission like this: Underwater search for iron/steel solely

[green]

If your mission is to search for "large" iron and steel objects, then simply set your main sample delay above (say) 50us, or maybe even higher. This will reject all smaller targets. A larger coil will also help in that respect, but would be a problem for diving use.

Was curious about decay of some ferrous targets. Couldn't think of a large ferrous target that I could chart. Charted three targets and some California ground. Targets have a decay slope very close to the ground, would loose a lot of signal if ground balance was needed. Maybe a different Tx current profile would show something different. Charted two different coils to see if they would chart the same, slopes very close to the same(straight line on log-log chart).

[kt315]

if your mission is to search for large... and with big coil.... so you need...

[Qiaozhi]

If your mission is to search for "large" iron and steel objects, then simply set your main sample delay above (say) 50us, or maybe even higher. This will reject all smaller targets. A larger coil will also help in that respect, but would be a problem for diving use.

[waltr]

Tough to do any type of discrimination with that MD and actually with any PI MD.

If you can find a way to reject iron then it can reject all but iron.
Typical PI MDs give a strong response to iron (ferrous) and since iron is much more commonly found I don't think getting an occasional response from non-ferrous is going to be an issue.

[Loola]

Hi all!

I am hoping to get some advice on how to adjust/improve my Surf PI 1.2 for a mission like this:
Underwater search for iron/steel solely.
I have searched this forum without finding answers to this question.
Many are looking for quite the opposite, reject iron/steel .

I would like the detector to go as deep as possible (our lakes often have very deep silt) and be optimised for Iron/steel.
Small sized items will never be in my interest to find.
Our lakes contain very little or no trasch

I have a search coil with this specification: Diameter 18” / 45 cm. Ohm 0.95. uH 370.
Is this coil a good start, or should I go bigger?
I will use the detector while scuba diving, so there is practical limitations to coil size.

I have an oscilloscope, if that will be needed.

Kind regards,
Leif Lindgren