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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! What is your "overall" opinion of the Nokta Impact?-------Thanks--------------Del
By Steve Herschbach
There is a previous thread with a lot of speculation about just what is going on with a couple of the Nokta Impact all metal modes, the Gen(D) and Sta(D) modes. The thought was that they are mixed modes - in other words modes that are running both all metal and disc in parallel.
The speculation garnered attention and we have now been provided this explanation directly from Nokta Software Team Leader Alper Tozan regarding these 2 modes:
''I read a lot of comments about Gen (D) and STA (D) modes in some forums and firstly, I want to thank you about all your positive thoughts. On the other hand, I want to clarify one thing. In some forum discussions, these modes are defined as ‘’mix modes’’. These modes are not mix modes as mix modes typically result from at least two different software algorithms or hardware circuits working at the same time for decision making to discriminate and detect metals. These mix modes also show characteristics of two or more different modes at the same time including handicaps of each signal processing.
Gen (D) mode, on the other hand, is a true threshold based all metal mode with motion that can discriminate metal without needing any other hardware or higher order software process level. So it always behaves like a classical true threshold based all metal mode but with iron tone and tone break.''
Frankly, for me that raises almost as many questions as it answers. Is an all metal mode that discriminates an all metal mode? Is it not instead a different kind of ferrous/non-ferrous discrimination mode? Whatever it is, it is unique, and that's enough for me! So I will do what I normally do and ignore what is going on under the hood and pay attention to just what it is these modes actually achieve by way of useful results in the field. More on that at a later date.
From Nokta Impact Owners Manual, pages 12-13:
Static Mode (STA)
This is a non-motion mode. In other words, the device will generate an audio response when you hold the coil stationary without swinging over the target. The audio response increases in volume as the coil approaches the target. This mode is recommended for larger and deeper metals.
In the STA mode, the device will generate the same audio tone for all metals and it will display the target ID on screen. At the same time, the ID scale will fill up to the right in proportion to the signal strength.
Target ID range is 00-99. 00-40 are ferrous and 41-99 are non-ferrous metals. You can discriminate out all IDs below a certain ID by using the Disc. setting and simply avoid these metals in the field.
When the device detects a discriminated metal, it will not produce an audio response or an ID. However, the ID scale will fill up to the right in proportion to the signal strength.
The threshold in this mode is internal and cannot be adjusted by the user. Changes in the ground and temperature may lead to drifts in the threshold. Threshold drifts will be reflected in the ID scale either in the positive way (right side) or the negative way (left side). The device may emit an audible response in the positive drifts but not in the negative ones. When the threshold drifts, pull the trigger once to retune the detector. Retuning periodically while searching in this mode is recommended.
IMPORTANT! For a more stable operation, try keeping the coil consistently at the same height above the ground where you retuned the detector.
IMPORTANT! If you retune the detector over a target, the threshold will drift to the negative side and the device will no longer detect the target until the detector is retuned. In addition, the depth of the detector will also decrease.
If the drifts are substantial and retuning does not improve the situation, increase the iSAT setting in the Expert Settings to a level where the drifts are eliminated (for detailed informa- tion on iSAT please refer to page 24). As the iSAT is increased, the device may detect weaker signals but will not be able to detect the targets anymore if you hold the coil stationary or sweep back and forth over the target. If the drifts still continue frequently, drop the gain to 39, decrease the iSAT and re-ground balance.
Static Delta Mode (STA (D))
In principle, it works the same as the static mode. The difference is that the static delta mode
will generate the same tone for ferrous and non-ferrous targets at fringe depths but it will discriminate the shallow ferrous targets by emitting a low iron tone. Also, Disc. setting is not available in this mode.
Please refer to Table 2 at the end of the manual for different settings used in STA and STA (D) modes.
General Search (GEN)
Different than the other modes, this mode features a threshold tone which is continuously heard in the background.
General Search (GEN) mode is used in 2 different ways in the IMPACT: 1) with the Disc. setting disabled at 0 2) with Disc. enabled (non-zero). When the device is first turned on, Disc. setting will be off. When the Disc. is set at 0, the device does not discriminate targets and detects all targets (metals, mineralized rocks etc.). ID of the detected target is shown on the display (except for negative hot rocks) and the same audio tone is provided for all targets. The audio tone increases in pitch as the coil approaches the target. This is the typical All Metal mode found in most detectors.
When using the Disc. Setting in this mode, the device will emit a low ferrous tone for all targets below the Disc. Setting, and a higher tone for all targets above the Disc. setting which changes in pitch as the coil approaches the target. Let's say you set the Disc. to 20. The device will generate a low iron tone for all metals with 0-20 ID and a higher tone for all targets with 21-99 ID. Upon target detection, the threshold will momentarily go silent and only the target audio response will be heard. The duration of the threshold's silence is directly related to the level of the iSAT.
Gain, threshold and iSAT settings in this mode are optimized to provide the best perfor- mance on different terrains. You can modify these settings based on ground conditions.
We recommend using the GEN mode when discrimination is not important and not using it in heavy trash areas or areas containing many hot rocks.
Audio Boost in the General Search Mode
This feature is not included in the settings on screen. Boosts the sound of weak signals received from small or deep targets making it easier for you to detect those uncertain targets. It is recommended that audio boost should be used on a temporary or as-needed basis because it will not only boost the target signal audio but it will also boost the volume of ground noise and false signals along with the threshold hum.
Audio Boost consists of 5 levels (b1-b5). At start up, the Audio Boost level is set to low (b1). To increase the Audio Boost level, pull the trigger and press the minus (-) button simultaneously. Audio Boost will only work in the GEN mode.
General Search Delta (GEN (D))
In principle, it works the same as GEN mode. The difference is that the Gen (D) mode will generate the same tone for ferrous and non-ferrous targets at fringe depths but it will discriminate the shallow ferrous targets by emitting a low iron tone.
A while back, I was going to buy the Rutus Alter 71, but, decided to wait for the Nokta Impact to be released. So, I went to an event in New Hampshire called BONE, (Best of the North East). I was hunting in a natural hunt on private property. I had just received my Impact on the April 21, and hunted on the 26th, and 27th. The place was a large farm with plowed fields, large open grass areas, and woods. The first day, I hunted a plower field, and the large grass area. I have to say that the Impact is so easy to use and set up. I started with the stock coil 7x11, DI3, 20khz, sen at 85, iron set a 2, default dis. At the end of the first day, I found the piece of a buckle in the plowed field, and a small button and half of a silver tumble in the grass areas. The Impact would sound off on the iron to let me know it was there, but with this iron volume, it was not annoying. Good targets were loud, but the iron tones soft. This was an excellent feature that I like very much. So on day two, I decided to hunt in the woods where an old cellar hole was. This was a site of an 1745 tavern. I set up in Deep mode, 20khz, stock coil, sen at 70, iron volume on 1, and default dis. As I stated to detect, I could hear iron all over the place, plus there was an electric fence that was causing others with Deus and CTX 3030 trouble. But my Impact ran very smooth. As I made my way around the perimeter, I continued to hear mass iron until I got a solid signal reading at 71 at about 8 inches. I dug down 6 inches and hit a rock, checked the hole again, and could hear the target, but also the iron all around on both sides. I removed the rock and I could see what looked to be a thin coin. To my surprise, it was an King George II 1749 farthing in excellent condition. I continued to hunt and a foot to my right, I got a another strong signal reading 83. At 4 inches down, I recovered a King George II half pence 1787. I couldn't believe it, I checked my hole again, and got another 83 with iron all around the target. I removed a second large copper without a date, but looks to be the same. I also found a large button and round piece of lead used for corks back then. So, everything I found was from the 1700 era. In closing, this is what impressed me about the Impact. It is well balanced, easy to use and set up, and offers lots of features. As an retired Garrett, Teknetics, Makro, Whites, and XP dealer, I have used a lot of detectors, and I have never found any to be able to find targets in the iron like the Impact. I not saying it the best out there, or better then the rest. But, it does a great job in iron and offers great value for its price point. I am not a tester, just an end user, and I am glad that I purchased the Impact.
By Nokta Detectors
Dear Valued Members,
This is to inform you that we just released an update for the IMPACT based on a few feedbacks which is now available for download at the IMPACT product page below:
R1_V1.13_V1.11 (System Software V1.13 / LCD Software V1.11)
Updates Made : Individual frequency shift values have been assigned for each frequency (5kHz/14kHz/20kHz) and the frequency shift feature has been improved overall.
By Steve Herschbach
Some random notes, and if you don't know what I am talking about as regards some detail of this machine or that I apologize.
Well, I finally updated my XP Deus with 11" coil to the version 4 update. Then I hauled it and the Nokta Impact with 11" and Teknetics G2 with 11" out for several hours of cross checking coin type targets. The G2 is a Gold Bug Pro variant running at 19 kHz and I put it up against the Deus at 18 kHz and Impact at 20 kHz. I acquired the G2 new recently to use specifically as a benchmark unit because I am very familiar with it and because in my opinion it does 19 kHz as well as it can be done. I spent hours swapping machines as the hunt machine, then cross checking the undug targets with the other two. Lots of settings tried, with the main goal to try and find some deep fringe type target or target in trash where any machine can get a clear and definable edge.
Well good luck with that. All I mainly did was impress myself again with what a little powerhouse the Gold Bug Pro/G2 is for the price. It is fairly mineralized ground but not the worst, 5 bars out of 7 on the G2 Fe3O4 meter, ground balance about 86. The only real "aha" moment was in learning the Impact really likes to upscale shallow small foil when in 5 kHz mode, but shoves the id back down to where it should be at 14 kHz or 20 kHz. All the machines like to upscale deeper aluminum in this ground.
All three seemed to get tricked in much the same way on certain targets, like a deep pull tab reading like a dime. For gold hunting purposes I do not mind machines upscaling low conductive targets, and in fact the Impact 5khz mode may have a benefit in nugget detecting because it does want to push light foil (and therefore small gold) higher. But for coin detecting upscaling aluminum is annoying. Pretty much par for the course however for mid to higher single frequency machines.
I found running the Impact in VLX1 was nice as I could flip over just one click to the Gen(D) mixed mode program for a dramatically different read and better target definition. Target id numbers in my ground are slightly higher in the "expanded ferrous" modes like VLX1 and VLX2 compared to DI3 and DI4.
The Deus V4 Gold Field program does seem to pack some extra punch now, be fun to get it out nugget hunting once the elliptical coil hits the streets. The new Deep mode really seems great while the new Hot mode is, shall I say it, interesting. First time I have used the X-Y screens also.
The G2 is what it is, almost no controls but it gets the job done with what it has, and good solid id. Deus and Impact in the other hand have countless options and programs to try, but by and large there is no magic bullet. Three great machines, I can hunt with any of them. It will take a lot more hours to sort it all out.
I find when running machines that are all hitting the VLF Wall that it is the "other things" that get my notice. The Impact is obviously the heavier of the three (4 lbs 4.7 oz / 1946 grams), although very well balanced, so I give the feel on my arm award to the G2 (3 lbs 1.5 oz / 1404 grams) and the Deus (2 lbs 4.0 oz / 1020 grams with 11" coil and control box). The G2 and Deus are neck and neck in the comfort department FOR ME* but the G2 feels ever so slightly better to me, I am guessing because the coil is lighter on the G2. The G2 slays both the Impact and Deus for speaker volume if run without headphones, but on the other hand it has no volume control so would be too loud for some situations.
Been awhile since I ran a Gold Bug Pro / G2 unit and caught myself when switching from disc mode to all metal when cross checking at one point and forgetting that the "big number" changes from target id in disc mode to ground phase in all metal mode, so I was looking at the ground phase instead of the little speedometer thinking it was target id for a couple goes. That one quirk always had me liking the F75 versus the Bug in all metal. I wish Fisher made a 19 kHz F75!
*On arm comfort is a very subjective subject. In particular it has a great deal to do with the size of a persons hands plus length and thickness of their forearm, and their height. You really can't take any one persons word on this subject as it is like buying hiking boots. What fits one person does not fit another. It is not all about detector weight by a long shot. Balance is very important as is the all important hand grip. I am 5' 11" with forearms on the thinner side and smallish hands. For instance, my forearm really bounces around in the large Impact armrest area. The Deus armrest which may be too small for some fits me better. For me personally, the 3.5 lb Teknetics T2 / Fisher F75 is the most comfortable detector I have ever used. It is superbly balanced and something about the hand grip that narrows to the top as it cants forward really makes my hand happy. I can squeeze the armrest shut to fit my arm. So if you find the F75 to be a great fit for you, my comments apply to you. If you hate the T2/F75 setup then what I have to say is less important.