Deus II And Reversed Reactivity?

[shopkins1994]

Hi Everyone!

I am using the Deus 2 to perform the Monte nail board test. If I set my reactivity to 0 it detects the coin all ways. If I set my reactivity to 5 it no longer detects the coin any way. I would think it should be the opposite -- setting a faster recovery speed should detect more easily between the nails and the coin. That does not seem to be the case. Any ideas why this would be? It seems with these test results that when in an area with high iron that we should set the Deus 2 to 0 reactivity?

Sam

[abenson]

Could be that in this case because all the items are on the same plain the coin is the stronger target. So that signal is overlapping the iron signal as the stronger of the 2. Interesting though I'll have to try it.

[shopkins1994]

I did square nails and a clad quarter in the middle. 

[Chase Goldman]

Best to use a dime and normalize to a more "common" reactivity setting of between 1.5 to 2.5.  When you use the extremes on the settings other factors come into play that result in unpredictable outcomes.

[shopkins1994]

25 minutes ago, Chase Goldman said:

Best to use a dime and normalize to a more "common" reactivity setting of between 1.5 to 2.5.  When you use the extremes on the settings other factors come into play that result in unpredictable outcomes.

Hi. I just retested with a clad dime and got the same results. After about 2.5 it starts to drop off with 5 getting no results.

Sam

[Jeff McClendon]

For me, that test is dominated by the four iron nail responses which partially mask the small coin. Running reactivity at 5 might in theory make more sense in order to unmask the dime but it is also possible to have the reactivity so fast that it attenuates the dimes partially masked signal too much. You can hear this by just testing all of the reactivity settings while swinging over the dime. From 0 to 5 the dime audio response will get smaller and quicker with more space in between.

Also, coil control, uniformity of coil height and swing length and speed are really important when doing Monte's NB. Swinging too short, too fast or just the opposite can really change the results.

[Chase Goldman]

19 minutes ago, Jeff McClendon said:

have the reactivity so fast that it attenuates the dimes partially masked signal too much

Bingo.

 

45 minutes ago, shopkins1994 said:

Hi. I just retested with a clad dime and got the same results. After about 2.5 it starts to drop off with 5 getting no results.

Sam

See above.  I rarely use reactivity above 2.5.  Primarily because there is no need (2.5 should be fast enough to provide sufficient separation for 99% of high target density situations, 0 is fast compared to other detectors but despite your results on the 2D go-no go Monte test, there are more restrictive real life 3D situations where reactivities in the 2 to 2.5 range are going to give you better results than 0 or 1) and you avoid the clipped duration "blip" target effect of the higher reactivity settings which favors the long/large targets (regardless of composition) like the nails.