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Book Excerpt: Modulation

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Could you explain exactly how to "use Pinpoint to check for solidity"? From the above excerpt? Thanks

 

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13 hours ago, FloridaSon said:

Could you explain exactly how to "use Pinpoint to check for solidity"? From the above excerpt? Thanks

 

How many times have you swung the Equinox over a sweet sounding quarter coin tone only to discover it was an aluminum can?  There are some tonal nuances a trained ear can tell the difference side-by-side in the ground, but it is even hard for a trained ear to tell the difference on widely scattered targets in a field or on the beach.  And you certainly can’t get a good handle on the target footprint with the processed search mode tones.  
 

Pinpoint mode to the rescue.
 

Since pinpoint is a non-motion mode (vs. normal detect mode which requires you to keep the coil in motion over the target to register a target tone), you can use it to quickly ascertain the relative size of shallower high visual or tone ID targets to give you an idea whether you are swinging over a coin sized object or potential junk with a much larger footprint such as a beer can or large falsing iron target (e,g., horseshoe.).  This is accomplished by tracing over the target with pinpoint engaged.  The larger objects will invoke the high pinpoint tone over a much larger footprint area than a smaller coin, ring, or button-sized target as the pinpoint tone rapidly drops off as the coil center crosses off the edge of the target footprint.  This method becomes less effective for significantly deeper junk targets as the relative pinpoint signal strength "footprint" shrinks even with larger targets as their depth increases (you can simulate this by lifting the coil off the ground while tracing something like a beer can).

You will probably dig the target anyway just to be sure, but at least this way your expectations are properly set such that you will be pleasantly surprised if it turns out to be a keeper rather than the other way around.

I personally use pinpoint more for target tracing, when I am in doubt about the true nature of a good sounding target, rather than going to pinpoint mode for pinpointing, because I can pinpoint pretty effectively by wiggling off high probability coin-sized targets.

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Chase,

I am also new enough with the 800 to always second guess my target identity! But that is how i dug a 1911 gold pocket watch a few months ago! I really don't mind digging most everything! I feel it's the only way to learn a detectors language! Even then, i refuse to miss anything! Except maybe those damn zincons!!

Thanks for the lessons, there much appreciated!👍

20190920_094706.jpg

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On 11/19/2019 at 7:58 PM, FloridaSon said:

Could you explain exactly how to "use Pinpoint to check for solidity"? From the above excerpt? Thanks

 

Move the coil to one side of the target, trigger--and sweep evenly across.  Try and do this the same every time so that the ratchet does not interfere  with getting a consistent pinpoint.  The signal strength and tone will tell you how solid the target is.  If you want to repeat--begin again to prevent a detuned (getting quieter with each pass) response from throwing you off.

There's more on this in the book.

cjc

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cjc and Chase;

This technique worked great on a 3 ft piece of rebar buried one foot deep at surfs edge on a saltwater beach! I dug one end to try and ID it but the length was clearly determined with the above textbook excerpt and both your explanations. 

Thanksgentleman!

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