Jump to content
Steve Herschbach

Where Will The Holes Be In The Fisher Impulse System?

Recommended Posts

Anyone who has used a White’s TDI much knows that the ground balance can be manipulated to exclude certain targets. This is less about conductivity as White’s sells it, but about target size. What that means is you can exclude high conductors and large ferrous and concentrate on smaller low conductors and small ferrous. Or you can exclude small ferrous and small non-ferrous and go for higher conductors and larger ferrous.

The system does not make gold hunters happy because to dig small gold you still dig small ferrous stuff. Or when you are digging larger gold you still dig nails.

My guess on the Impulse is that it is using at least two “ground balance” points to bracket the most common ring responses, which tend to be lower mid-range targets. It would be quite a balancing act tuning out both the smallest stuff and the largest stuff and just hit the sweet spot. I personally think this could be a powerful method for essentially cherry picking rings while eliminating most small ferrous and large ferrous. There still will be a class of mid-range ferrous targets that read good - I promise the system can’t be perfect.

The flip side however is that at least two large “holes” are going to have to exist as a result. One that misses smaller gold targets, like earrings and chains, and possibly the smaller thin rings. And then on the top end very large heavy men’s rings and silver rings, and most coins may also be lost.

The solution will be to turn off the discrimination and go back to digging everything. Hopefully there will be some ability to tweak the discrimination as target / trash mixes do vary somewhat and shifting the accepted range up or down would be beneficial.

I am just guessing based on what I know about how a PI works and how one could potentially discriminate out a class of targets. I could see a very acceptable trade being made, more depth at the expense of certain target classes.

Yet I wonder how the general public will react to videos displaying numerous gold items, especially large ones, being completely undetectable by the Impulse in discrimination mode? The wiser among us may understand what’s going on and the trades being made, but if I know one thing about a lot of folks, the idea the machine misses good stuff won’t fly too well. Witness the silver dollar on edge fiasco with the Equinox, or the similar issue with the early Gold Bug models.

Anyway, don’t take this as being more than speculation, but it is something that the more knowledgeable among us will want to find out quickly once the Impulse hits the streets. It should be easy to find out, just air test with a large range of jewelry targets running from tiny to large and check the results. And the same with ferrous. Unless a Pulse Devil miracle machine is in the works, and I am betting that’s not the case, there will be some definite caveats to deal with when employing the discrimination system.

For me it’s kind of a non-issue. I’d be happy with the machine as a straight up pulse digging everything. It’s the ergonomics and price along with the finely tuned low pulse delay that have me looking more than some magic discrimination system. Anything it does there will be just a bonus. I will actually be surprised if the nugget hunting terra version has any discrimination at all due to the possible issues I am outlining. It would tune out most natural gold nuggets. Optional blocking of high end nail type signals would be of more benefit to nugget hunters in small gold areas. It would risk missing large nuggets but in some places that’s not much of a worry.

Fisher Impulse AQ Data & Specifications

Fisher Impulse AQ pulse induction metal detector

  • Like 6

Share this post

Link to post
Share on other sites

Completely agree with everything you have mentioned Steve.
Manufacturers mustn’t get too cute with a PI.......let them be raw and powerful as they were designed to be. I will never detect having the knowledge that I am walking over a nice fat gold ring and that is why I run my TDIBH with GB Off........no “holes” and better depth. The beach version of the AQ should be a straight PI...... and it would be cheaper to buy. Don’t let the AQ try to be all things to everyone. If Fisher plan to develop other versions then the case for a simple, powerful, straight PI for the beach is even stronger. White’s did a very good job on the TDIBH......Fisher could learn from them.


  • Like 4

Share this post

Link to post
Share on other sites

The latest posts by LE.JAG have indicated that the “hole” at the upper end has been steadily nibbled away at - and now lies “above” even massive rings and 22kt gold. 24k is likely still “in the hole” - which is to say, excluded along with ferrous targets, silver and other high conductors when the discrimination function is enabled. 


Share this post

Link to post
Share on other sites


Some very good points here.  For me the problem with the Impulse is that for some bizarre reason First Texas has chosen to remain almost completely quiet on the machine.  The questions of "holes" in gold targets are very legitimate and it is surprising to me that Fisher hasn't taken the time to at least release some sort an update on this detector. I mean, they've selectively teased everyone with short videos and drops of prototypes at shows, so why not just tell those of us honestly what's going on? 

  • Like 1

Share this post

Link to post
Share on other sites

It’s mainly me who has teased everyone by posting stuff about this since June 2018. Fisher showed a prototype at one show in Germany this last winter.

It’s a totally new thing for them. The entire design team was the subject of an “acquihire” of Alexandre Tartar and his fellow “Manta” team members.

It is by all accounts a more complex and tighter tolerance device that First Texas is used to producing. That and the likelihood that a dedicated beach PI will be a “niche” machine and therefore not a mass market seller, and the likely high production cost - make it understandable why they are proceeding very carefully.


  • Like 2

Share this post

Link to post
Share on other sites

Don’t worry Rick, your reputation as unofficial spokesman for First Texas is quite secure. You do more to promote their detectors than anyone that actually works there.

  • Like 3
  • Haha 4

Share this post

Link to post
Share on other sites

That all sounds excellent, especially the small gold results. I am in total agreement that any discrimination system has trade offs, even in the best VLF detectors. Those trades are perfectly acceptable as long as we know what they are so we can apply proper judgement on where to employ discrimination and where to dig everything. The big downfall for PI has always been its affinity for ferrous targets making it simply impractical for use in some locations. Impulse AQ addresses that issue and I expect the best places to use one initially will be exactly those locations that PI users have avoided until now.

I personally have no doubt this detector will be very productive in the right locations and look forward to using one myself. I have not owned a waterproof PI since I sold my ATX and have been waiting patiently for something better to come along. For me the waterproof TDI was too little too late. I wanted one from the very first day I used a TDI but after years of being ignored in my lobby efforts I found by the time White’s finally made one better things like the Impulse were on the horizon.

Very kind of you to post that information LE.JAG.....  thank you! It’s especially good to hear the Terra version is in beta testing, that bodes well for a dual machine introduction.

  • Like 5

Share this post

Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now

  • Similar Content

    • By pinpointa
      Could there be an early book on the horizon?
    • By LE.JAG
      he is in production // finally ..
      I find it amazing that your dealer does not speak

      a French seller already takes pre-orders
      without delivery date ....
      price announce France / Europe 2490 euros

    • By Steve Herschbach
      This detector is all but certain to appear, and probably before the end of 2019. I have been on a quest to get a high power ground balancing pulse induction metal detector that is reasonably light in weight and in a somewhat standard metal detector housing, preferably waterproof. Whatever detectors I personally use must have dealers and service support in the U.S.
      Edit 3/2019: The Manta has been officially named the Fisher Impulse AQ, a development that happened later in this very thread. It has also been revealed a gold prospecting model is under development. You can follow along here to get the latest information later in this thread and see the history. Or quick jump to the Fisher Impulse AQ Specifications & Data & Fisher Impulse AU Specifications & Data pages.

      The challenge I have for Fisher or anyone else is to make a dry land ground balancing PI that weighs under 4 lbs yet is more powerful than a TDI SL. The alternative is waterproof but under 5 lbs. The price must be under US$2000.00 Waterproof Pulse Induction Metal Detectors Compared
      The Fisher Aqua Manta (edit 3/2019 now known as Impulse AQ) has been rumored for some time, and confirmed by First Texas as a project nearing completion. Prior threads:
      January 2015 New Fisher Pulse Induction
      January 2018 New First Texas PI Under Development
      June 2018 Aqua Manta Pulse Induction Beach Detector
      The long story short is this is a project by Alexandre Tartar. The Manta is most likely an offshoot and improvement on the orginal Eric Foster Goldscan circuit. Alexandre has built at least three major prototype devices before the rights were acquired by First Texas. The following photos and information is derived from this thread where the V3 prototype is sold.
      Here are the basic specs as described in advertisement (the seller is French and translating):
      "I sell a "prototype" Manta v3
      There are only three copies of this detector and it is the best of three ....
      (See mantametaldetectors website)
      Pulse induction, works exclusively with mono coils to the beach, possibly for the land, but no ground control
      Calibrated for low conductors, gold and platinum, among other. Delay 7us of 17 volts more sensitive, deeper and faster than Deepstar
      Equipped with a coil, Manta, latest generation
      she has one month, the quietest and most efficient on the market, all brands included. (it will operate on TDI and Deepstar)
      Connector Type TDI, it accepts all coils (mono) of TDI / GPX
      Weight: 1.5 kg without battery that is worn at the belt
      headphone jack and on / off switch on the battery pack (lipo) supplied charger
      more than six hours of detection at full power.
      Carbon Rod Anderson + extra cane down
      braided nylon belt military style
      All the possible settings and need a good PI
      SAT speed, TX frequency, noise threshold, delay, volume, sensitivity....
      The delay was 7us , lets see gold ends
      very thin rings, earrings, jewelry hollow that other detectors can not see
      and of course, the wholesale jewelry it goes deeper
      Ferrous recognition by a double beep well marked"
      What I find interesting is this note "Pulse induction, works exclusively with mono coils to the beach, possibly for the land, but no ground control"
      Yet here is the picture that accompanies the advertisement. Now remember this is from March 2016, almost three years ago. The prototype clearly has labels for ground controls...

      Alexandre Tartar Manta V3.0 prototype
      The control markings as seen above:
      Volume Threshold Sensitivity Sat Speed. Motion. (recovery speed) Tx Frequency (transmit frequency, usually to offset for EMI mitigation) Pulse Delay. GB Type (the shorter the pulse delay, the more sensitive to tiny metal and salt water) Ground Balance (usually a ground balance control, but ad says this is lacking?) Statements by First Texas suggest version 1 of the new machine is aimed at beach use and may not be suitable for land use (gold prospecting). That in turn makes me think work on the ground balance system is lagging and may be key to the future of the machine. Will it be beach only, or have a future for gold prospecting?
      I have to assume the unit will be competitive when it comes to the horsepower, or why bother? Until now the Eric Foster Deepstar is generally acknowledged as one of the deepest beach PI detector’s ever made. And the ad says “more sensitive, deeper and faster than Deepstar”. That being the case what really has my interest is the weight and compactness being displayed. The following photo collage from the advertisement shows the size of the control box and belt mounted battery:

      Alexandre Tartar Manta V3.0 prototype
      Granted the battery is belt mounted, but that is one tiny control box. I have to think that First Texas can slim down the circuit board and use a top notch integrated rechargeable battery and get this machine into a very compact package - hopefully waterproof and with wireless headphone capability built in.
      Well, that's about all I know about this one. This thread will collect any new information as it is available. This is one of a couple detectors I am watching so fingers crossed for a 2019 release. It is encouraging that Alexandre's original website at http://www.mantametaldetectors.com/ has been taken over by First Texas and is displaying this banner:
      Fisher Research Labs - New Pulse Induction metal detector COMING SOON!

    • By Nuke em
      Anyone out there know any information on this machine ? It supposed to be being tested and could be really interesting when released .
      2019 Update: The Manta is now called the Fisher Impulse AQ - see Fisher Impulse AQ Detector Data & User Reviews
      May be able to discriminate Iron out .
      You Tube this .  AQUAMANTA A1 TESTS HARDELOT . All in capitals . 
      It is compared to the Sovereign and CTX , the Aqua is the last one tested . Unfortunately LIKE the Equinox most of the time before release , its in a foreign language .
    • By Steve Herschbach
      My VLF detectors are rapidly sorting themselves out and I am satisfied I am doing about as good in that regard as can be done. There really is only one area of metal detecting left that is bugging me.
      2019 Update: The Manta is now called the Fisher Impulse AQ - see Fisher Impulse AQ Detector Data & User Reviews
      The Garrett Infinium was the first waterproof ground balancing PI and not a bad first effort. White's TDI might have improved on it but White's never did a waterproof TDI. Surprisingly, Minelab has never done what I would consider to be a true waterproof saltwater beach hunting PI. The SDC 2300 really is a prospecting detector first and second. I finally ended up with the Garrett ATX, which currently sets the bar for a waterproof ground balancing beach and water detector.
      Yet the ATX housing was designed more for military use than beach detecting. The coils are overly expensive due to an integrated rod design. Worse, the detector weighs in at 6.9 lbs and cannot be hip or chest mounted.
      In a sign of faith I am going to sell my ATX and wait on whatever First Texas has in the works. As Rick Kempf posted here previously, First Texas hired Alexandre Tartar and purchased the rights to produce a version of his Manta PI Project. And to quote First Texas engineer Carl Moreland from this thread "Yes, we've hired Alexandre. Yes, we are working on PI. I was personally working on PI before hiring Alexandre, but now we are seriously working on PI."
      Fisher has not made a PI since the Fisher Impulse was discontinued back around 2013. This collaboration with Alexandre Tartar gives me hope that First Texas can get something out in the next year or two. My bar is low - a waterproof ground balancing PI at least as good as the ATX in a more ergonomic package. Seems fairly doable. Another company that may come out of nowhere all the sudden is Nokta/Makro as we know they are working on a PI. I don't know, but I think this is First Texas' game to lose at this point. So there you go, ATX going up for sale and a spot held open for whatever company can meet the challenge. Good luck First Texas - I am rooting for you!
    • By Steve Herschbach
      No, I actually do not know what the new Fisher Impulse Terra will be called. It is just that I doubt it will be called the Impulse Terra and Impulse AU seemed like a good pairing with Impulse AQ. Probably wrong but I can change it when we find out for sure. The main thing is this dry land gold prospecting version of the Impulse AQ is 99% certain at this point, so I wanted to start tracking it as a separate model with what is know about it so far. Which is not much. WE know testing is taking place with an 8" coil but do not know for sure if that will be the stock coil or not. It would be a good choice for small gold but not good for covering ground or for larger deeper gold. OK though if that's what they go with. Presumably a 12" coil is a possibility as stock or as an option.
      It will have to ground balance, and it may or may not have ferrous rejection capability. I personally hope it does, as some areas are full of ferrous trash and missing some gold is worth it to be able to use a PI in those areas.
      Anyway, will be updating as I find out stuff. I'm kind of more interested in the beach model myself as i have nugget detectors already, but it will depend just what the feature mix is that will swing me one way or the other.
      Fisher Impulse AU Specifications & Data
  • Create New...