We tested the 18 inch Coiltek AI coils to see if they helped detecting on noisy salt lakes.
In February 2011 when we undertook our test just happened to be the wettest its been for along time around Mt Magnet and Cue.
Where, why and how is described in more detail at our webpage Salt Lake Metal Detecting. which shows you where to metal detect on salt lakes and how to target salt lakes to find gold.
Udo and I bit the bullet and purchased a 18 inch Coiltek Anti Interference (Salt) coil so we could test it and see how it performed against the Minelab 5000 used on "salt/gold" settings with a DD attached.
We are great fans of the Minelab 5000 machine but there is no comparison between the performance of a Minelab 5000 with even a small DD using "salt" settings and the same machine using a Coiltek AI coil of 18 inch diameter.
Neither of us was a keen salt lake metal detector operator but with the Anti Interference or "Salt lake" coil we can see the possibilities for this type of metal detecting and it is probably an area where good nuggets can still be found, even if only due to the difficulty of detecting in the salt environments.
AI Coils were originally designed to combat power interence from Electric power lines but they are great in combating interfence from heavy salt deposits.
They eliminate interference noise that you will get in a Mono or DD thus you can hear the gold signals.
Even the Minelab 5000 set to "salt/gold" setting with a Mono or DD will not have the same depth as an AI Coil.
The Minelab 5000 manual suggests using "Cancel" with a DD coil in extreme salty areas - the problem with this is that you will lose around 80+% of your depth and sensitivity if you do this!
You dont lose as much depth - but that is relative, if your coil is screaming you cant hear the gold anyway!.
They will allow you to detect where other coils just will not go.
During our test we just used the standard DD settings on a minelab 5000 with the 18" AI Coil and it was very quiet in the salt ground we could get to.
The 18" coiltek mono and 11' Minelab DD in "Salt/gold" was just too noisy to detect in the same area. The more "noise" in the machine the more chance of missing small gold signals.
You needed to swing the coil slowly to eliminate salt interference noise.
The 18" anti interference coil was a heavy and would be difficult to swing all day.
Being 18" round coil it is ideally suited to flat salt lake country but on the shoreline amongst the rocks and salt resistant plants it is difficult to swing and cover the ground properly.
- we dont think the 18" Coiltek AI coil is still being made, it is not shown on the Coiltek website at September 2014.
The coils are limited in depth and sensitivity in other ground.
They come in a number of sizes;
It's your decision whether you keep one of these coils in your armoury but if you detect in WA around Salt lake areas they are definitely worth a try.
Return to Metal Detector Coils Page from Coiltek AI Coils page