my Nail Board Performance Test as you demonstrated in your videos.
First, I want to say 'Thank You' for using this test scenario and the video work you did. I've been relying on this testing device for over 23 years to compare different types and sizes of search coils on many, many detector makes and models to help sort through them all to select the best detectors available to maintain in my personal detector battery. The bulk of my regular hunting sites are very littered with iron nails ... plus other assorted ferrous discards like rusty tin and such, and I need the best unmasking performance I can get.
Second, the standard 7X11 DD coil does a splendid job compared with most competitive models using a similar-size and type search coil, even though that is never the coil I would use in such a densely littered site with close-proximity nails and coins. That coil I reserve for open-area searches such as plowed fields, large grassy lawns at big parks, sports fields or private yards.
Third, your FORS Relic demonstration with the round 5¼" DD coil is a prime example why this detector model and that size and type search coil are my #1 favorite team when working very heavily iron contaminated sites. Performance afield is exceptional with the features the FORS Relic provides for such searches where the Iron Audio Volume can be reduced to a comfortable level when accepting most ferrous targets like you were using in your test.
Questions / Observations / Suggestions & Opinions:
[size=small]►[/size] To confirm your posted settings, by "ID3" were you referring to using the Di3 [size=small](Three Tone)[/size] search mode, or was this a reference to a Discriminate setting [size=small](ID Mask)[/size] of '3' which would be accepting iron nails?
[size=small]►[/size] I did note that your search coil sweep speed was a bit faster than what I use when working any iron infested site, regardless of search coil size. I always use a slower and more methodical sweep speed as that helps to better process the ferrous trash and pass along a better response from a desired target in the mix.
[size=small]►[/size] I also noted that most of your side-to-side coil sweeps were pretty close to working the center-axis of the coil directly down the lined sweep route for a dead-center search coil pass. That's the way it should be done, especially when hunting in dense iron where you would also want to use ample overlapping on progressing movement across such a site. I hope viewers noted that as it was easy to associate the coil's center with the white-colored bolt & nut mounting hardware you use.
[size=small]►[/size] With a slightly slower sweep speed you will usually enjoy a little cleaner hits, and I will suggest two different set-up methods to re-test the FORS Relic or an other detector to see what seems to work best for hunting in nail infested sites. These methods are:
1.. Adjust the Discriminate setting of the Relic ID Mask to '11' so that you just barely reject the four iron nails before placing a coin in the #1 spot. Also, to make comparisons similar to those I do to duplicate the initial coin & nail encounter, be sure to use an Indian Head 1¢ or modern Zinc 1¢ which has a close conductivity. By just barely rejecting the iron nails you can compare a detector's performance with models that have a proven record of handling nail plagued locations but responding very well, such as the Tesoro units with ED-120 Discrimination when they are adjusted to the minimum Disc. setting.
2.. Use the Di2 [size=small](Two Tone)[/size] Discriminate mode. I prefer to use Di3 when I am working sites that have a heavy concentration of rusty tin as it helps provide more tell-tale audio classification, but when I am hunting trash-free places, or those where iron nails are in abundance as the primary offending target, the Di2 mode will give a much more distinctive audio response on the NBPT. I think you will note the obvious audio clarity when using Di2 on thrr NB, both with a Disc. setting of '3' that accepts the nails as well as '11' where they are just barely rejected. Definitely a much more 'Dig Here!' type of audio response.
The Nokta FORS CoRe got me hooked on their exceptional performance in dense iron contaminated sites and I rely on both of mine, and my three FORS Relic models stepped it up a bit in denser iron littered sites and can unmake desirable targets quite well. My two Nokta Impacts are also top contenders in my Regular-Use Detector Team and while most hunting is at 14 kHz I make the switch to 20 kHz to come close to the performance afield I get from my 19 kHz FORS Relic ... when using comparable search coils.
[size=x-large]*[/size] Oh, one more thing to try, if you can find the search coil, is to use the 5½X10 Concentric coil on the FORS Relic. That is an impressive coil that I keep mounted full-time on one of my Relic devices for low-to-moderate trashy sites where nails are the primary offender. It out-performs the 5½1X110 DD and standard 7X11 DD.
Monte