2 null points

[GCuster]

Hi all,

I am not new to metal detecting, (20+ yrs), starting with a Whites 6000D then moving into a Fisher CZ-6, but I now have a new E-Trac and new to this forum.
After all the reading of Andy's book and the user's manual, I do have a question.
Today I did an "air test-coins mode" on a variety of different coins from copper, silver and gold coins.
Everything seemed to come up where I expected they might except I got a null on both the large cent and silver half.
Pull tab and bottle cap were 12-22 and 12-24.
Where would you suggest I start?
Thanks in advance.

 

[Yeasty]

If you are getting a null from a large cent and silver half, they have been discriminated out. Try Quick Mask with an open screen and you will see that those coins ring out loudly and give an appropriate TID. You need to adjust your discrimination pattern to accomodate them.

 

[GCuster]

Thanks a lot Yeasty

 

[DirtyDeedsDugDirtDeep]

Speaking of nulling....
I was showing my son some air tests with various coins to show what numbers would come up.
And for the most part, they were the same as ground targets.
But then a weird thing happened....... we had a baggie with maybe 25-30 clad quarters in it that nulled out when passed near the coil !!
We looked at each other like...WTH ??!!
Then we had a plastic container with mixed change in it, and the same thing happened.
Individual coins were no problem.
The machine with a 6x8 coil would pick up a quarter at 8-10" no problem.
So what's going on here?
I'm not using some tight discrimination pattern.
Anybody else try this ???
If not, try it and let me know what happens.
Thanks!

 

[moonshine]

Id be curious to know what the numbers would be on that, just quick-mask and scan again.

 

[stasys]

http://www.youtube.com/watch?v=uaDvZJpb5MU

 

[EtracTom-AdirondacksNY]

ground needs to be set to difficult and trash set to high.

 

[DirtyDeedsDugDirtDeep]

So,what would the explanation be for this anomaly ??

 

[DiggerODirt]

On the large containers of coins, the E-Trac is most likely OVERLOADING...Not Nulling...To pick up the large Silvers, you have to have the 50 line opened from like 1-50 - 5-50...You might get some large trash here, but you won;t miss the large Silvers either.

HH,

 

[DirtyDeedsDugDirtDeep]

Digger,
The thing is, when my Etrac overloads it doesn't go silent.
It gives off a weird vibrating or oscillating tone.
Our case was just like Stasys' video: the theshold just dropped off like it was iron.
I'm pretty sure my machine was set on difficult ground and high trash; but honestly I haven't taken the time since to double check the settings. But I will !