Here is a Pic of a PI detector with a meter.

[jackaroo]

It is a Home built machine . It needs lots of work but the guy that built it does not have a LOT of resources, lives on SS Diability. He says another pof his prototypes can give depth indications of KNOWN sized objects RINGS in particular.

 

[king george 111]

Does it work well??...how deep on sand ..looks good keep me posted on upgades and trials thanks

 

[UK Brian]

There's been several P.I.'s with meters going back 25 years or more. The problem was they all used a standard VLF type discriminating circuit to provide the ferrous/non ferrous discrimination and the primary search mode that was pulse was far deeper and could cope with wet salt on a beach which was where the discriminating circuit fell down.

You might be able to find pictures on the web of Eric's P.P.D.1, Protovale's Pulse Analyst, the Groundhawk etc.