A customer air test of the Impact
- Thread starter ghound
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5 mile
Forum Supporter
Perhaps something isnt right with that air test, I was not impressed, when I saw tests done with the Rutus Alter 71, my attention went in that direction.
What in the world does a Rutus Alter 71 have to do with this Nokta impact air test ?
Florida Tabdigger
Elite Member
Thanks for the video. Air tests are great for general comparisons, but you will always detect stuff deeper after it's been in the ground for a while. It's kind of a apples to oranges test. In my Florida sand, air tests are great, but when your in mineralized ground, you really cannot rely on it. But again, it's great info.
Donsell
Forum Supporter
He's saying that the Alter 71 performed poorly on the air test but is fine in the field and suggesting perhaps the Impact may act the same way.
5 mile
Forum Supporter
Actually Beebs is right, it has nothing to with this thread. In correcting Donsell, Rutus performed exceptionally well on air test, but Im not allowed to say that.
But the impact did not perform poorly. Not in my opinion anyway from noting the frequency that was used. That is why I pm'ed Bill S a while ago asking if he would use that frequency while hunting a tot lot environment, it has to be killer for small jewelry, tot lot form but the weather was not cooperating all that well then.
The video was using high frequency. High frequency have shorter wavelengths which is great for detecting small objects like tiny gold/jewelry bits. The number of waves per second in kilohertz. 20 kHz is 20,000 waves per second. The lower the frequency the longer the waves are, the deeper the waves will penetrate the ground but someone who actually knows more about this should be telling the facts than I. I don't know only what I 've read.
so from the video, High frequency is used, maybe one should not suspect to achieve great depth ?????
The video was using high frequency. High frequency have shorter wavelengths which is great for detecting small objects like tiny gold/jewelry bits. The number of waves per second in kilohertz. 20 kHz is 20,000 waves per second. The lower the frequency the longer the waves are, the deeper the waves will penetrate the ground but someone who actually knows more about this should be telling the facts than I. I don't know only what I 've read.
so from the video, High frequency is used, maybe one should not suspect to achieve great depth ?????
Donsell
Forum Supporter
I got that from a post on another forum. He reported that his Alter 71 had a bad air test but good performance in his test garden.
It is relevant in supporting the notion that you can't always use an air test to determine the quality of a detector.
I don't have an Alter so I can't validate if it's true or not. And it was just one post, so perhaps there are other air tests that have been better.
Why would you not be allowed to say that?
5 mile
Forum Supporter
Like Bibelot said keep posts pertaining to Impact, I veered, apologies.
No reason to apologize. We participate as individuals, our opinions will vary greatly at times from one another. I think the key is to respect each others opinion ,even if we disagree with them. I am guilty of wearing my heart on my sleeve as well, it is very cumbersome at times.
Donsell
Forum Supporter
I'm the one who should apologize. I shouldn't have tried to explain someone else's post.
But the impact did not perform poorly. Not in my opinion anyway from noting the frequency that was used. That is why I pm'ed Bill S a while ago asking if he would use that frequency while hunting a tot lot environment, it has to be killer for small jewelry, tot lot form but the weather was not cooperating all that well then.
The video was using high frequency. High frequency have shorter wavelengths which is great for detecting small objects like tiny gold/jewelry bits. The number of waves per second in kilohertz. 20 kHz is 20,000 waves per second. The lower the frequency the longer the waves are, the deeper the waves will penetrate the ground but someone who actually knows more about this should be telling the facts than I. I don't know only what I 've read.
so from the video, High frequency is used, maybe one should not suspect to achieve great depth ?????
Good response.
You picked up on the frequency being used and the targets being tested.
Also gain was at 80 I think.
I run my unit a lot using DI 99 gain maxed at 99 and she purrs on my medium mineralized ground.
ghound
Elite Member
What you need to note is that the guy finding small hammered silver, these are really thin and fall way down the scale to the foil area on many detectors, a friend was telling he was finding it more so with the Impact.
So higher khz are favoured for these targets, probably not for most US coins though.
Yep,,thin coins,,20khz seems to like. The 1916 merc I found was the thinnest merc I have ever dug,,,extremely worn.
ghound
Elite Member
Here's an example, this typical hammered penny is roughly the same dia as a dime but about a third of the thickness.
The dime weighs 2.23g and reads 104 on my machine.
The silver hammered penny weighs 1.31g and reads 53 on my machine, in the foil range.
A friend said these hammered are coming in low 20's in the DI modes, not sure where the same dime registers though.
The dime weighs 2.23g and reads 104 on my machine.
The silver hammered penny weighs 1.31g and reads 53 on my machine, in the foil range.
A friend said these hammered are coming in low 20's in the DI modes, not sure where the same dime registers though.
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