D&P-OR

Nokta Impact Vs G2 / F19 On Gold

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Hello everyone.----Steve, I respect your input & opinions--always have!----Here's a couple of questions I have for you.---Considering detector performance---With the Nokta Impact running at 20 kHz and the G2+/F-19 with their 19 kHz---IYO, which one of these detectors would give the best performance for hunting for (smallish) gold?-----Also, there has been a lot said (hype?) about the Impact with its 5, 14 & 20 kHz frequencies being able to replace other detectors running in that range.---A sort of "one for all" (if you will).-----Do you feel that could truly be the case?-------I said two questions---here's another one! :smile:  What is your "overall" opinion of the Nokta Impact?-------Thanks--------------Del

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One of my projects for this summer is to get a more detailed answer to that question. The short answer is I personally think that for just chasing gold nuggets with stock coils the units you mention are close enough as far as performance so as to not matter to me. 18 - 19 - 20 kHz is dead, beat to death, and each new one is as good as and no better than any of the rest for gold nuggets. Just look at the overall feature list and pick whichever floats your boat. If all you care about is nuggets a Gold Bug 19 kHz model will do as well as any mentioned at under 3 lbs and for less money.

The part about the Nokta Impact that intrigues me is the 15.5" x 14" DD coil. In general large coils can be counterproductive on hotter VLF machines for two reasons. First, units like the Gold Bug Pro are actually too light, and hanging a large heavy coil off the front of them is an ergonomic nightmare. That Fisher 15" DD on any of the machines it is made for really sucks to swing. The Impact on the other hand is almost made to handle large coils - much better balance. Next to my Garrett ATX and Minelab GPZ the Impact with 15" coil will be the light weight option!

The other problem with single frequency detectors is a large coil "sees" too much ground. At higher frequencies this works against the machine in high mineral ground. There is too much blowback from the ground, and the operator has to lower the sensitivity by a large amount to compensate. The net result is in bad ground you often get no more depth with a large coil on a 18 kHz and higher unit, and possibly even less depth in severe ground. Usually a large coil just gets you more ground coverage.

nokta-impact-15-13-dd-coil.jpg

However, in lower mineral ground a large coil on a hot VLF can act like a "poor mans PI" but with full discrimination. Yet because of the issues outlined above some hot VLF detectors don't offer coils larger than about 14" x 8" in size, even if you wanted one. The Impact does. 

The kicker is that the Impact, much like the Minelab Eureka Gold, can switch to lower frequencies. If I have the 15.5" x 14" DD on the Impact, I would start at 20 kHz. If I got into bad ground, I would first lower sensitivity. If forced to drop below 70 or so (to be determined) I would go to 14 kHz and push the gain back up. If I were forced at 14 kHz to drop under sensitivity 70 (guessing still), I would now drop to 5 kHz and push the gain back to max. If 5 kHz is not working, time to go to smaller coil or break out a PI.

The Deus has my interest because it also can frequency switch, but again large coils are not a great idea due to the physical design, so in the case of the Deus it is the high frequency small coil that has my greatest interest. The Impact is just the opposite - it is the large coil option that has my interest.

I don't think the commentary about the Impact being able to replace many other detectors running in the 5 - 20 kHz range is hype, but it is not anything unusual either. There are piles of great do it all machines out there that can all be said to replace many other machines. The fact is however all have little areas where one might be better than another. I think the Impact has an edge over the CTX for gold nuggets. But the CTX has the edge for salt water detecting. So it goes for almost any pair of detectors you want to pick for me to discuss. The one perfect do everything detector has yet to be invented. I am however on a quest to try and find one VLF detector that comes closest to fitting the bill for me personally in that department.

Some commentary on Impact, Deus and G2 here

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The handle on the impact looks very comfortable, the whole design is superb which looks to be less of a pain on the joints and wrists than the S - Handle style. If the performance matches the looks..this detector would make a nice backup to a GPX. 

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Handles are like hiking boots - different fits for different people. I do not have large hands, and I find the Tek G2+ tapered oval handle as pictured above (same as T2 & F75) to be perfect for me. My hand also really likes the GPX grip. My hand does not like a hard grip as much - the ATX rock hard post needs foam -but it mostly is about shape. The Impact post is harder than most and slightly squared off. Not bad, but I think for me it needs a single wrap of foam tape not only to soften it up but to round it off, though I really don't need it to be any larger diameter. Another person might come to exactly the opposite conclusion.

The balance of the Impact however is perfect due to the weight being to the rear. It feels lighter than the 4.26 lbs would imply. Right at a pound lighter than my CTX 3030, another well balanced machine. I like the rounded oval type grip on my CTX better than the rounded square Impact grip.

Big plus of Impact over CTX - three piece rod assembly with lower rods that cost $19 versus hard to pack CTX two piece design with lower rods that cost from $100 aftermarket to $175 genuine article!

CTX waterproof and Impact not.

Click on photos for closeup view.

nokta-impact-vs-minelab-ctx-3030-metal-detector.jpg

nokta-impact-handle-vs-ctx-3030-grip.jpg

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Thanks Steve.-----I read your other post on the Deus, Impact & G2 also---very informative.------Del

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Frequency is just one aspect. Ground balance, and more importantly Audio and threshold stability are what propels or sinks any potential gold machine.

Can't speak of the G2 or F19 as I haven't used either, but the Impact has excellent audio, and the iSat adjustment is very effective.  It also has a very adjustable audio tone in the all-metal mode. 

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Well Nenad to put it in more familiar terms, how does the Impact at 20 kHz compare to the X-Terra 705 running at 18.75 kHz, both in all metal "Prospect" modes with roughly equivalent coils?

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Haven't put them side-by-side yet.

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My bet without even using them side by side is that "the units mentioned are close enough as far as performance so as to not matter to me."

Sorry, but I really am getting bored with 13-20 kHz single frequency in particular. If the Impact could not frequency switch I would hardly be giving it a look myself. I guess it was the AT Max that broke me. I saw it and thought "Just Another Mid Frequency Detector". Boring!

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