Impact

[oldtimerROB]

In the GT the Impact has real grunt in the deep mode.eg 20 inches deep compared to 8 inches deep with the all metal mode on a 1.5 inches diameter ball of silver foil.The Impact is so sensitive it picks up too many false signals for me to dig.Someone has to advise on the optimal settings on goldfields to counter this,but then you might miss a nugget but digging up all the signals is unpractical. I use DI2 on the hills as it goes 50% deeper than all metal as deep mode will not ground balance there due to very high mineralisation.I will have to test how deep COG mode goes on the hills but I suspect not very deep.The 15 inch coil,the IM 40 is too heavy for prospecting but I would like to fit a 13 inch coil.Black Dog makes a good one for the Impact but not available here.Nokta should have marketed one on the internet as there is some interest from consumers.

 

[PhaseTech]

Sorry but Deep mode is just not able to get 2.5 times the depth of All-Metal mode, especially in mineralised soils. Deep mode is a higher gain mode, designed for use in low-mineralised soils, and for use with a slower sweep speed. DI2 can go a little deeper than all-metal/GEN but again not 50%. I think you need to spend a bit more time learning the unit. You say you are getting lots of false signals, that is probably due to using Deep. Use VLX modes or Gen in mineralised soils. In Gen mode you have the advantage of adjusting the iSat to maintain a smooth threshold - this is how you maximise sensitivity on the Impact.

If you want to find gold with the Impact, I would be focusing on trashy areas (where it is hard work with a PI unit), and use a small coil, as the Impact separates targets from ferrous extremely well. In this case I would be using Gen Delta mode, or if the trash is really thick, DI3, or if trashy and mineralised VLX2.

Just be aware that the ferrous range of the ID's changes with different modes, in Gen and VLX it is 0-40, and in DI3 it is 0-15. Nuggets coated with iron can ID very low, and even in the iron range, so be careful.

 

[oldtimerROB]

Thanks for your recommendations on the Impact.I can,t run the tests again as I have been living in Eastern Europe for a while but plan to return to Victoria and live on the diggings next autumn.I have every confidence and stand by my figures.I have had extensive use of the Impact contrary to what you think.We seem to have different Impacts?possibly running different software versions?Another testI did at South Wedderburn was on a gold specimen containing 1-2 grams of gold.Again I seem to remember All Metal got approx. 3 inches depth but DI2 got 5 inches in about 90% on the min. meter.Deep is not a low mineralisation mode as it can balance at up to 80% min. but can be used in most areas on the diggings of the GT except the hills thereafter I prefer to use DI2 or 3.All Metal is good for finding hot rocks as it has disc. which can be set at 01 or 02, and can find very small targets of 0.1 gram at 3 inches in low min.It is very susceptible to mineralisation and going from low to high min. it,s depth will be drastically reduced,possibly to half.I have not used audio enhancement to get extra depth as the manual does not recommend it for general search.DI2 got two sharp signals on a hill at Goldsborough which was still there at 12 inches depth but at 18 inches depth of the dug out hole had disappeared. It must have been something like a mineralised nodule.
All the GT diggings I have been to are relative clean of junk except for tin foil.That's when DI modes come in handy as you can filter out the tin foil to either mask it on a ID setting of 17-19 or have it come up as a ferrous signal.One possible explanation why All Metal gets only low depth is the iSAT is set at 06 whilst DI and DEEP is set at only 01?
I still plan to buy a 13 inch coil for the Impact.A Karma coil is available for purchase online worldwide from the Netherlands for 129 Euros.

 

[Ridge Runner]

I Think PhaseTech is talking about actual In Ground tests Not Air Tests, Not only is he a Nokta Dealer but he must be One of or The Most Skilled Detector Field testers on the Planet Bar none so rest assured that he is reporting the facts.

 

[Jarrod84]

OTR, can I ask why have you persisted so long with the impact and not bought a dedicated pulse induction gold detector when you main target is gold?

 

[oldtimerROB]

I did ground tests too and unlike others did them in highly mineralised soil.
I have been prospecting on and off over 40 years and have enough experience.
Thirdly I paid only $1280 for the Impact against about $5000 for a new PI unit.It was either that or nothing as it was a big burden on my finances to save that up.Then $800 for camping equipment.If I am happy with the unit I don't see a problem.

 

[ronniecruisin]

You need to find a TDI pro oz like I Did. Great PI and the only PI than can discriminate. I'm finding it a pleasure to use. All analogue controls too. :argh:

 

[Jarrod84]

No issue, just that for spending all that money and all your experience chasing gold I'd like to have a gold finding detector.

Sometimes though the challenge of finding gold with a lesser machine can be more fun I guess.
I get a lot of enjoyment finding gold with equinox 600 even though I have a better detector I can use.

I only ask though because I know someone who often asks me for advice and they are also persisting with an impact and haven't found any gold after a few years, hopefully I'll be able to organize a day with him and get a closer look at how the impact performs next to my equinox 600 and gpx when chasing gold.
If that ever happens I'll post about my finds.

 

[ronniecruisin]

Hi. Jarrod84. I briefly went back to a VLF recently. A machine I had owned once before and regretted selling because of its wireless design and shear pleasure to detect with. New coils have been introduced since then for gold hunting so I figured Id give it another go. What did I find??? Still a pleasure to use as above But! At the end of the day its still a VLF.! Twittery and temperamental in our Oz conditions. I've been detecting for many years and have picked up a lot of gold in that time but the truth is every piece of gold found by me has been with a Pulse machine.! They are generally super quiet in our ground for the most part and they go a lot deeper than any VLF. Now if I were living in the States it would be a different story. I'd be toting a VLF just about everywhere!

 

[oldtimerROB]

Why I like the Impact is that it is very stable in Victoria,s GT,even at Wedderburn.It is not twittery and a delight to use on the goldfields.I feel I just need a 13 inch coil to cover more ground as I am used to a 16 inch coil for prospecting..The stability of this unit is ideal for large coils but you will loose some benefits like better separation..Fitting a different brand on a Nokta may need a factory reset in which case I think I would rather get the IM40 coil from Nokta and use some sort of shoulder sling to balance the heavier unit.

 

[ronniecruisin]

Hi Rob. My experience with nokta goes back to the fors gold. I do agree with you. Nokta is a very forward thinking company and makes very nice machines. Their approach to detectors is quite different from others. Not surprised you are having fun with yours. Regards.. Ronnie.

 

[oldtimerROB]

Hi Ronnie, Living in Belarus so sorry for the delay.I really miss the Victorian bush and can't wait to get back for next winter season,s detecting.I will be living and camping out in the bush detecting from May to September 2020 and giving the Impact a thorough going over which last time I could not do as my Belorussian wife was in Victoria for 2 years and she could not stand the cold nights camping in the van. I don't see what the problem is with the Impact as I have explained many times to our members it is very stable in out GT soil or gravel except for Deep mode which becomes sluggish on signals up at Wedderburn and cannot be GB,d on hills generally.The Impact has the notch filter feature which can be set to mask the silver foil encountered on goldfields which I don't think you can do with the PI,s.GEN mode is very good at discriminating out hot rocks with a distinct quacking sound.
Only problem generally I can see with the Impact is it has too many modes and features which can become intimidating to the average user and hence it is taking users too long to sort out what to use on gold.I wasted a whole season using GEN until I found out it is only good for small shallow targets.I now use DEEP and DI2 at 20 Khz.I still have not figured what settings to use to cut out false signals which you get in the DI modes.The manual advises what to do to eliminate them adjusting the gain, discrimination and Isat levels,but this is a real specialised field as the wrong settings will cause depth to be lost.No one in the world has yet posted any recommendations for this in very highly mineralised ground.
Nokta is improving its products by giving its customers what they want.The Kruzer is less complicated and has less modes,is waterproof and weighs less.The Anfibio the same and has a 13 inch coil and hits a silver mercury dime at 14 inches deep in the DEEP mode and 14 Khz.Watch calabash digger on Youtube.

 

[oldtimerROB]

The Black Dog range of coils from Spain have been on my wishlist for 2 years but unavailable in Australia.But recently they have opened an online store available worldwide but I have not tried it yet.
The 13 inch maximo is a new rounder design for the Impact and I would chose it over the old more oval shaped 13 inch coil that has been for sale for the last 2 years and now is old stock.The Black Dog Impact got good reviews in the past and I would prefer it over the Karma.
The maximo weighs 460 grams and goes 40 percent deeper than the standard 11 inch Nokta coil,but it covers much more ground,a win win situation if you are detecting virgin ground around the old diggings and looking for larger nuggets 1/4 oz. and over.

 

[oldtimerROB]

One good reason to buy the Impact is for gold prospecting as it is totally immune to the very high mineralisation in Victoria's GT. However it is 4 and a half years old and no one has made a performance comparison between it and the Anfibio Multi and Anfibio 19 and Equinox 800. So we are none the wiser which is better value on the goldfields. Also target depth comparison with the Gold Kruzer on a 0.3 gram nugget and 4 gram nugget.

 

[ronniecruisin]

Hi. Rob. Ooooooooh. Totally immune to high mineralisation is a big claim. I know you love your impact but at the end of the day no VLF machine copes perfectly in high mineralisation. It's been the bane of VLFs since time began. That's why Pulse machines have the depth advantage over them in this country. Now having said all the above VLF machines have come a long way over the last few years re better handling of our ground. But there is a limit as to how far you can flog the same technology and I reckon it's just about done. My multi Kruzer should in theory be a similar performer to your Impact. They both have similar frequencies.

 

[oldtimerROB]

Hi Ronnie, it really is totally immune as I claim. I first reported this on my first outing with the Impact back in May 2017 in a thread entitled " Impact Tames Havelock Goldfield " and soon after one at Dunolly. No one on the forum even made a comment about it which shows the animosity out there to anything that would dare challenge the Minelab brand and I even got lots of abuse over it. I used AM mode for 12 months and then was disappointed with its performance and started using the DEEP mode and in certain areas it became too sluggish especially at Wedderburn so I used D12 and it worked perfectly as a backup mode. I want to try out D!3 when I get back from Europe as it has the gold tone ie 16 to 66 ID which is a mid tone. The ID readouts don't work in most parts of the GT so you have to go on tones. The notch filter might not work either in very high mineralisation as I only tested it at a picnic area near Castlemaine at Harcourt. I don't know if the Impact will work when I get back to Australia as it will have lain there unused for over 4 years and I was looking to buy another detector here in Belarus as they sell at 70% of Aussie prices. I was looking at the Anfibio 19 for prospecting and now interested in the new 61 Khz detector which is fully automatic and claims it can be used on any goldfield but I am wary it will overload in the GT. I commented on the false signals and raising the Isat setting, but if this does not work at least with my Impact I have the option of trying the 14 Khz frequency. If that does not work I will give up prospecting and go beach detecting in SA.
The Impact is noted by others that it is a very good machine to use large coils with as it handles the mineralisation well and better than other brands for use with large coils.
I am confused on this new Legend Detector as I could not watch the whole video
Seems like the Impact is more for the professionals and the Kruzer Multi more for the hobbyists. Seems like the Impact did not sell too well and they bought out a more simplified machine which really took off. In hindsight I am glad I bought the Impact because of its immunity to mineralisation as that is what it is all about here in the GT.

 

[ronniecruisin]

Hi. Rob. Well. If it's working for you that's fantastic. If it's as good as you say it is I'm sorry I didn't get one instead of the Kruzer. I thought given the similar frequencies the two would be close competitors. Maybe Nenad would like to chime in here as he knows the ins and outs of both these machines. Would be interested in hearing his take on this. When you do get back personally I would be very happy to meet up with you if possible. You have some very interesting ideas Rob. There is always something new to learn in this game. Regards Ronnie. :argh:

 

[PhaseTech]

"Totally immune to high mineralisation is a big claim." Yes it is - it is a known limitation for VLF units. The milder the soils, the less they will be affected and you can drive the sensitivity levels up and achieve impressive depth.

"I thought given the similar frequencies the two would be close competitors." Yes, with like for like settings, with the same sized coil, the two are very very similar. It would come down to an individuals expertise with each machine, coil control, sweep speed for the chosen mode, and learning to identify target signals, and I'm talking audio responses, particularly in VCO modes like DI2 (2 Tone) and Gen.

 

[ronniecruisin]

Hi. Nenad. Thanks for your input. Sooooo is 2 tone actually the equivalent of the D 12 mode Rob seems to favour with his Impact?? Would be nice to know a bit more about these modes between the two machines to better understand how they relate to performance. Also what size the standard coil is on the Impact? The same or bigger? Rob seems to favour the D12 mode to achieve more depth than AM mode. Can't imagine that to be the case myself. Every machine I've ever owned always had better depth in AM. And it's certainly the case with the Kruzer too. Significantly so.

 

[PhaseTech]

Yes Di2 (not D twelve) is short for 2-tone discrimination mode. They are the same mode, aside from possibly having different Gain stages internally, but only the Nokta tech guys could answer that.